The preventive effect and mechanism of Dayuanyin in hypoxic pulmonary hypertension through NF-κB signaling pathway / 药学学报

Dayuanyin (DYY) has been shown to reduce lung inflammation in both coronavirus disease 2019 (COVID-19) and lung injury. This experiment was designed to investigate the efficacy and mechanism of action of DYY against hypoxic pulmonary hypertension (HPH) and to evaluate the effect of DYY on the protection of lung function. Animal welfare and experimental procedures are approved and in accordance with the provision of the Animal Ethics Committee of the Institute of Materia Medica, Chinese Academy of Medical Science. Male C57/BL6J mice were randomly divided into 4 groups: control group, model group, DYY group (800 mg·kg-1), and positive control sildenafil group (100 mg·kg-1). The animals were given control solvents or drugs by gavage three days in advance. On day 4, the animals in the model group, DYY group and sildenafil group were kept in a hypoxic chamber containing 10% ± 0.5% oxygen, and the animals in the control group were kept in a normal environment, and the control solvent or drugs continued to be given continuously for 14 days. The right ventricular systolic pressure, right ventricular hypertrophy index, organ indices and other metrics were measured in the experimental endpoints. Meantime, the expression levels of the inflammatory factors in mice lung tissues were measured. The potential therapeutic targets of DYY on pulmonary hypertension were predicted using network pharmacology, the expression of nuclear factor kappa B (NF-κB) signaling pathway-related proteins were measured by Western blot assay. It was found that DYY significantly reduced the right ventricular systolic pressure, attenuated lung injury and decreased the expression of inflammatory factors in mice. It can also inhibit hypoxia-induced activation of NF-κB signaling pathway. DYY has a protective effect on lung function, as demonstrated by DYY has good efficacy in HPH, and preventive administration can slow down the disease progression, and its mechanism may be related to inhibit the activation of NF-κB and signal transducer and activator of transcription 3 (STAT3) by DYY.

Progress on the mechanism of PDGF-BB signaling pathway in the pulmonary vascular remodeling of neonatal hypoxic pulmonary hypertension / 国际儿科学杂志

Neonatal hypoxic pulmonary hypertension(HPH)is a common acute critical disease in NICU, and is one of the diseases leading to neonatal death.At present, the specific pathogenesis is still unclear.Current studies have shown that pulmonary vascular remodeling is an important pathological feature of pulmonary hypertension, and the excessive proliferation and migration of pulmonary artery smooth muscle cell is the main cause of pulmonary vascular remodeling.Platelet-derived growth factor(PDGF-BB)is a powerful mitogenic factor which involved in cell proliferation and migration.Currently, plenty of studies have found that PDGF-BB plays an important role in multiple diseases, including tumor, atherosclerosis, pulmonary hypertension and pulmonary fibrosis.In view of the mechanism of PDGF-BB, this article reviews the possible mechanism of PDGF-BB in pulmonary vascular remodeling with neonatal HPH, aiming to provide a new direction for the therapies of reversing pulmonary vascular remodeling with neonatal HPH.

Maxing xiongting mixture regulates factors relevant to lung reshaping and vascular remodeling of hypoxic pulmonary hypertension rats / 中国组织工程研究

BACKGROUND: Hypoxic pulmonary hypertension is a key link in the progression from chronic obstructive pulmonary disease to cor pulmonale. Its severity is closely related to disease development and prognosis. Current treatments cannot prevent or reverse disease progression. Maxing Xiongting Mixture has significant effect on hypoxic pulmonary hypertension with the syndrome of intermingled phlegm and blood stasis. OBJECTIVE: To study how the Maxing Xiongting Mixture regulates relevant factors of lung reshaping and vascular remodeling of hypoxic pulmonary hypertension rats with the syndrome of intermingled phlegm and blood stasis. METHODS: Seventy Sprague-Dawley rats, 5 weeks old, were randomly divided into normal group (n=10) and model group (n=60), where acute cor pulmonale model was prepared by injecting 50 mg/kg monocrotaline solution (1%) intraperitoneally, followed by forced smoking and swimming 6 days a week lasting for 4 weeks. Except for 10 rats in the normal group, there were 46 model rats in the model group. According to the normal distribution of body mass, 40 rats were selected and randomly divided into 4 groups: model group, high-dose Maxing Xiongting Mixture group (MH), low-dose Maxing Xiongting Mixture group (ML) and fasudil group, with 10 rats in each group. Rats in MH and ML groups were respectively given Maxing Xiongting Mixture at 20 g/(kg·d) and 5 g/(kg·d), respectively and those in the fasudil group were given fasudil at a dose of 10 mg/(kg·d). Other groups were given equal amount of saline. Administration was given intraperitoneally and intragastrically, once a day for 14 days in total. RT-PCR was used to test the expression of factors related to lung reshaping and vascular remodeling, including RhoA, stromelysin 1 and tumor necrosis factor-α mRNAs. An approval for the study was obtained from the Ethics Committee of Chengdu University of Traditional Chinese Medicine (approval No. 2017-03). RESULTS AND CONCLUSION: Compared with the model group, the expressions of RhoA, stromelysin 1, and tumor necrosis factor-α mRNAs were significantly lowered in the MH group (all P 0.05). To conclude, Maxing Xiongting Mixture, which is similar to fasudil, intervenes lung reshaping and vascular remodeling of hypoxic pulmonary hypertension rats with the syndrome of intermingled phlegm and blood stasis by inhibiting the expressions of RhoA, stromelysin 1, and tumor necrosis factor-α mRNAs.

MicroRNA-143–5p modulates pulmonary artery smooth muscle cells functions in hypoxic pulmonary hypertension through targeting HIF-1α

This paper explores the potential mechanism of microRNA-143–5p regulation effects on pulmonary arterysmooth muscle cells (PASMCs) functions in hypoxic pulmonary hypertension (HPH) via targeting HIF-1a,which may offer a new idea for HPH therapy. PASMCs were transfected with mimics control/miR-143–5pmimics or inhibitor control/miR-143–5p inhibitor. We used Western blotting and RT-qPCR to detect the proteinand mRNA expressions, CCK-8 assay to detect cellular viability, Annexin V-FITC/PI staining and caspase3/cleaved caspase-3 protein to evaluate cellular apoptosis, transwell migration experiment for cellularmigration measurement and Dual luciferase reporter gene assay to prove the target of miR-143–5p. Cells underhypoxic condition presented the decreased protein and mRNA expressions of a-smooth muscle actin (SM-aactin), Myocardin, smooth muscle myosin heavy chain (SMMHC), and smooth muscle-22a (SM22a),Calponin1 and Hypoxia-inducible factor-1a(HIF-1a), the increased cell viability and miR-143–5p level; Overexpression of miR-143–5p obviously reduced vascular smooth muscle-specific contraction marker proteinlevels and cellular apoptosis, increased cellular migration of PASMCs with hypoxia stimulation; Low-expression of miR-143–5p caused the opposite changes, while co-transfected with Si HIF-1a blocked thebeneficial effects of miR-143–5p inhibition on PASMCs under hypoxia. MicroRNA-143–5p can promote thephenotype conversion, proliferation and migration of pulmonary artery smooth muscle cells under hypoxiccondition through direct targeting of HIF-1a.

Clinical Observation of Bosentan in the Treatment of Hypoxic Pulmonary Hypertension in Neonates / 中国药房

OBJECTIVE：To observe the ef fectiveness and safety of bosentan in the treatment of hypoxic pulmonary hypertension（HPH）in neonates. METHODS ：From Jan. 2014 to Mar. 2019，a total of 82 HPH neonates hospitalized in the department of neonatology of our hospital were selected as research subjects. According to whether or not receiving bosentan therapy，50 cases were included into bosentan group and 32 cases into non-bosentan group. Meanwhile ，another 25 non-HPH neonates with serum sample retention time and general information such as gestational age at birth and day age matching the HPH group were selected as the control group. All neonates with HPH were given continuous intravenous infusion of Dopamine hydrochloride injection 5 mg/（kg·min）until PASP was normal. On this basis, neonates in the bosentan group were additionally given Bosentan tablets 1 mg/kg（fed after dissolving with appropriate amount of water for injection ）for q 12 h，72 h. The relationship between serum ET- 1 levels of neonates with HPH and PASP was analyzed ，as well as PASP before and after treatment and therapeutic efficacy between bosentan and non-bosentan groups ，the changes of arterial blood gas indexes and ADR in 3 groups were compared. RESULTS ：Before treatment ，the serum ET- 1 levels of bosentan group was （164.3±115.3）pg/mL，which was significantly higher than （41.9±3.7）pg/mL of control group and positively correlated with PASP level （r＝0.864，P＜0.001）. Total response rate of bosentan group was 90.00％，which was significantly higher than 71.88％ of non-bosentan group （P＜0.05）. After 72 h of treatment ，PASP of 2 groups was decreased significantly ，compared with before treatment （P＜0.001），and the bosentan group was significantly lower than the non-bosentan group （P＜0.05）. The PaO 2，SaO2，PaCO2 and OI in 3 groups was significantly improved compared with that before treatment （P＜0.001），and the PaO 2，SaO2 and OI in the bosentan group was significantly higher than that in the non-bosentan group （P＜0.05）. During the treatment period of bosentan and within one week after drug withdrawal，there was no significant change in serum LDH ，AST，ALT and Scr levels in neonates. There was no statistically significant difference in the incidence of feeding intolerance ，anemia，reduced WBC and reduced PLT in 3 groups（P＞0.05）. CONCLUSIONS： Bosentan can improve the oxygenation status of neonates with HPH, reduce PA SP，and short-termmedication is safe. com

Role of Ca2+ in hypoxic pulmonary vasoconstriction / 中华危重病急救医学

In acute hypoxia, pulmonary vascular will contract and divert blood to better ventilated area to optimize ventilation/perfusion matching, which is known as hypoxic pulmonary vasoconstriction (HPV). In chronic hypoxia, irreversible pulmonary vascular remodeling can be induced, characterized by pulmonary artery middle smooth muscle cells and the outer fiber cell hyperplasia in luminal stenosis and pulmonary artery hypertension (PAH) eventually. Furthermore, PAH can cause increased ventricular afterload, and right heart failure in severe cases. Pulmonary artery smooth muscle cell (PASMC) elevated Ca2+ concentration is one of the most important factors of its contractions, proliferation and migration. Recent studies on Ca2+ promoting in HPV were summarized in order to provide evidence for clinical prevention of hypoxia and therapeutic PAH.

17β-estradiol Attenuates Hypoxia-induced Pulmonary Vascular Remodeling via Downregulating miRNA-21 Signaling Pathway / 中国循环杂志

Objectives: To explore the effect of 17β-estradiol (E2) on hypoxic pulmonary hypertension (HPH) and explore if the effects were mediated through suppressing pulmonary artery smooth muscle cells (PASMCs) proliferation by targeting miRNA-21 (miR-21). Methods: Animal experiment: A total of 32 healthy female SD rats with castrated surgery were randomly divided into 4 groups: normoxia group, normoxia+E2 group, hypoxia group, hypoxia+E2 group (n=8 each). The rats in normoxia+E2 group and hypoxia+E2 group received subcutaneous injection of E2 20 μg/kg/d, and the rest groups received subcutaneous injection of equal volume saline. The hypoxic groups were placed in the hypoxic chamber (24 hours per day for 8 weeks) to establish HPH model and normoxic groups were kept in the room air. The pulmonary artery remodeling, mean pulmonary artery pressure (mPAP), right ventricle hypertrophy index (RVHI) were observed. Real-time PCR and Western blot were used to detect the levels of proliferation cell nuclear antibody (PCNA) and miR-21 expression in pulmonary artery. In vitro: human pulmonary artery smooth muscle cells (hPASMCs) were randomly divided into 3 groups: normoxia group, hypoxia group, hypoxia+E2 group. The levels of cell proliferation in each group were tested by MTT after 24 hours. Real-time PCR and Western blot were used to detect the levels of PCNA and miR-21 in cells. Results: Animal experiment: compared with normoxia group, the hypoxia group showed obviously thickened pulmonary artery wall, increased mPAP and RVHI, and significantly increased expression of miR-21 and PCNA (P<0.01);above changed were significantly attenuated in hypoxia+E2 group (P<0.01). In vitro: compared with normoxia group, the hypoxia group showed obvious proliferation and significantly increased expression of miR-21 and PCNA (P<0.01);compared with hypoxia group, the proliferation of hPASMCs and expression of miR-21 and PCNA were obviously reduced in hypoxia+E2 group (P<0.01). Conclusions: E2 could effectively reduce mPAP, attenuate the degree of right heart hypertrophy and pulmonary vascular remodeling, the protective effect may be mediated through downregulating miR-21 and PCNA expression, and subsequently inhibiting the proliferation of hPASMCs.

Protective effect of salidroside on rats with hypoxic pulmonary hyperten-sion by suppressing oxidative stress / 中国病理生理杂志

AIM:To study whether salidroside plays a protective role in hypoxia-induced pulmonary hyperten-sion by suppressing oxidative stress.METHODS: Sprague-Dawley rats were randomly divided into 4 groups: normoxia (N)group,hypoxia for 4 weeks(H4)group,low-dose salidroside(hypoxia for 4 weeks and treatment with salidroside at 16 mg/kg,H4S16)group and high-dose salidroside(hypoxia for 4 weeks and treatment with salidroside at 32 mg/kg, H4S32)group.The mean pulmonary arterial pressure(mPAP), the weight ratio of right ventricle/(left ventricle+sep-tum)[RV/(LV+S)]and vessel wall area/vessel total area(WA/TA)were evaluated.The levels of malondialdehyde (MDA)in the serum and lung tissues were detected by colorimetric method.The levels of 8-iso-prostaglandin F2α(8-iso-PGF2α)in the serum and lung tissues were measured by ELISA.The activity of superoxide dismutase(SOD)in the serum was analyzed by hydroxylamine method.The expression of NAPDH oxidase 4(NOX4)and SOD1 in the lung tissues was determined by Western blot.RESULTS:Compared with N group,the levels of mPAP,RV/(LV+S)and WA/TA in H4 group were significantly increased,which were apparently attenuated by salidroside injection in a dose-dependent manner. Meanwhile,salidroside administration apparently decreased the levels of MDA and 8-iso-PGF2αin the serum and lung tis-sues,as well as the expression of NOX 4 in the lung tissues.Besides,compared with N group, the activity of SOD in the serum and the expression of SOD1 in the lung tissues in H4group were significantly decreased,while administration of sali-droside increased the activity of SOD in the serum and the expression of SOD 1 in the lung tissues in a dose-dependent man-ner.CONCLUSION:Salidroside protects the pulmonary vessels from remodeling and attenuates hypoxia -induced pulmo-nary hypertension by inhibiting oxidative stress.

Protective effect of heat shock protein 70 on lungs in newborn rats with hypoxic pulmonary hypertension / 中华实用儿科临床杂志

Objective To investigate the protective effect of adenovirus mediated heat shock protein 70 (HSP70) on lungs in neonatal rats with hypoxic pulmonary hypertension (HPH).Methods One hundred and twenty-eight 7-10 d healthy Wistar neonatal rats were randomly divided into HPH model group and control group.HPH group was divided into saline group,empty virus group,and HSP70 group according to the transfection solution.HPH model was established in the hypoxia cabin of 80 mL/L nitrogen oxygen mixed gas after transfection.The mean pulmonary artery pressure(mPAP) was measured after 3,7,10 and 14 days of hypoxia in each group.The mRNA and protein expression of HSP70,hypoxia inducible factor-1 alpha(HIF-1 α),endothelin-1 (ET-1) and inducible nitric oxide synthase(iNOS) in the lung tissues of neonatal rats were detected by using reverse transcription-PCR and Western blot respectively.Results (1) The mPAP level was significantly higher in saline group (M,Q:12.00,2.50;15.00,2.00;18.00,1.75;20.00,2.25) than that in control group (M,Q:9.50,4.75;10.50,1.00;13.00,1.00;15.50,3.25),and the differences were significant (z =-3.28,-3.40,-3.34,-3.06,all P ＜ 0.01);and the differences were also significant between empty virus group (M,Q:13.50,2.00;15.50,1.75;18.00,1.00;22.00,4.25) and control group (z =-2.83,-3.42,-3.40,-2.97,all P ＜ 0.01) in 3,7,10,and 14 days;but there was no significant difference between HSP70 group (M,Q:8.50,4.00;10.50,1.00;13.00,1.00)and the control group in 3,7,and 10 days (z =-0.43-0.00,-3.06,all P ＞ 0.05).(2) The expressions of HSP70 mRNA among the groups were statistically significant(F =6.321,9.669,6.333,all P ＜ 0.01),and the expressions of HSP70 protein also had significant difference(F =16.463,3.637,17.749,all P ＜ 0.01).(3)The level of HIF-1α mRNA in saline group was significantly higher than that of the control group,and the differences were statistically significant (q =4.312,9.106,6.151,all P ＜ 0.01);and the level of HIF-1α mRNA in empty virus group was also significantly higher than that in the control group,and the differences were statistically significant (q =3.982,9.235,5.352,all P ＜ 0.01) in 3,7,and 10 days;hypoxia in HSP70 group was lower than that of the empty virus group in 3,7 days,and the differences were statistically significant (q =6.083,11.031,all P ＜ 0.05).The level of ET-1 mRNA in saline group was significantly higher than that in the control group(q =5.112,10.086,6.264,all P ＜ 0.01),in empty virus group was significantly higher than that in the control group,and the differences were statistically significant (q =4.182,12.238,5.864,all P＜0.01) in 3,7,and 10 days,but in HSP70 group it was lower than that in the empty virus group in 3,7,and 10 days,and the differences were statistically significant (q =6.912,10.235,7.021,all P ＜ 0.05).The level of iNOS mRNA in saline group was significantly higher than that of the control group,and the differences were statistically significant (q =4.998,8.056,5.369,all P ＜0.01),in empty virus group was significantly higher than that in the control group,and the differences were statistically significant (q =4.778,10.138,5.154,all P ＜0.01) in 3,7,and 10 days,but in HSP70 group it was lower than that in the empty virus group in 3,7,and 10 days,and the differences were statistically significant (q =7.819,9.838,6.156,all P ＜ 0.05).The level of HIF-1 α protein in saline group was significantly higher than that of the control group in 3,7,and 10 days,and the differences were statistically significant (q =3.146,3.012,4.106,all P ＜ 0.05),in empty virus group was significantly higher than that of the control group in 10 days,and the difference was statistically significant (q =3.468,P ＜ 0.05);but in HSP70 group it was lower than that in the empty virus group in 3,7,and 10 days,and the differences were statistically significant (q =3.876,4.108,4.021,all P＜ 0.05).The level of ET-1 protein of HSP70 group was lower than that of the saline group,the differences were statistically significant(q =3.367,2.983,3.246,all P ＜ 0.05),in HSP70 group was lower than that of the empty virus,and the differences were statistically significant (q =3.268,2.678,3.567,all P ＜0.05).The level of iNOS protein in saline group was significantly higher than that in the control group in 3,7,and 10 days,and the differences were statistically significant (q =3.360,3.567,3.567,all P ＜ 0.05),but in HSP70 group it was lower than that in the empty virus group,and the differences were statistically significant (q =3.126,3.908,3.087,all P ＜ 0.05).Conclusion Adenovirus mediated HSP70 can improve the HSP70 expression in HPH,down-regulate the expression of HIF-1 α,ET-1,iNOS,and reduce pulmonary arterial pressure.

Effect of PASMC apoptosis on reversal of hypoxic pulmonary arterial remodeling during reoxygenation and its related molecular mechanism / 中国病理生理杂志

AIM: To explore the effect of pulmonary arterial smooth muscle cell (PASMC) apoptosis on the reversal of hypoxic pulmonary arterial remodeling during reoxygenation and its possible mechanism.METHODS: Male SD rats (n=24) were randomly divided into normoxia for 4 weeks group, hypoxia for 4 weeks group, reoxygenation for 1 week after hypoxia for 4 weeks group and reoxygenation for 6 weeks after hypoxia for 4 weeks group.Right ventricular systolic pressure (RVSP), right ventricular hypertrophy index, pulmonary arterial medial thickness (MT) and medial area (MA) as well as autophagy and apoptosis in the pulmonary arterial medial layer were examined during hypoxia-reoxygenation.The rat primary PASMCs were divided into normoxia for 48 h group, hypoxia for 48 h group, reoxygenation for 24 h after hypoxia for 48 h group and normoxia for 72 h group to explore the changes of PASMC autophagy and apoptosis following hypoxia-reoxygenation.Finally, primary PASMCs were divided into normoxia for 72 h group, reoxygenation for 24 h after hypoxia for 48 h group and reoxygenation for 24 h after hypoxia for 48 h + chloroquine (inhibitor of autophagy) group to investigate the effect of PASMC autophagy during hypoxia on the apoptosis during reoxygenation.RESULTS: After hypoxia for 4 weeks, the RVSP, during right ventricular hypertrophy index, MT and MA increased significantly compared with normoxia group (P<0.05), and gradually decreased during reoxygenation.The expression of LC3 in the pulmonary arterial medial layer increased evidently after hypoxia and gradually reversed during reoxygenation.Moreover, the P62 and cleaved caspase-3 expression decreased after hypoxia compared with normoxia group, and increased markedly following reoxyge-nation.The expression of cleaved caspase-3/PARP in rat primary PASMCs decreased significantly under hypoxia (P<0.05), and increased evidently during reoxygenation.The expression of P62 and LC3-II decreased markedly under hypoxia (P<0.05).After inhibition of PASMC autophagy under hypoxia, the expression of cleaved caspase-3/PARP decreased remarkably during reoxygenation (P<0.05).CONCLUSION: The PASMC apoptosis participates in the reversal of hypoxic pulmonary arterial remodeling, and the PASMC autophagy under hypoxia might facilitate its apoptosis during reoxygenation.

Advances in differential roles of HIF-1αand HIF-2αin the pathogenesis of hypoxic pulmonary hypertension / 中国药理学通报

Hypoxia-induced factors(HIFs)are the main regula-tors for the response of hypoxic environment.They are involved in hypoxia-related lung tissue cell damage and abnormal cell pro-liferation,among which,HIF-1αand HIF-2αplay the most im-prominant roles.This paper reviews the current researches of HIF-1αand HIF-2α,focusing on their structural and functional similarities and diversities,as well as their roles in the patho-genesis of hypoxic pulmonary hypertension.

The expression and significance of circulating microRNA of rats with hypobaric hypoxia-induced pulmonary hypertension / 西安交通大学学报(医学版)

Objective To investigate the expression of circulating microRNA (miRNA) of rats with hypobaric hypoxia‐induced pulmonary hypertension (HPH) .Methods Commercial rat miRNA microarray was employed to detect and analyze the circulating miRNA profile in the serum samples of Sprague‐Dawley rats with hypobaric hypoxia‐induced HPH and controls .Furthermore ,differentially expressed candidate circulating miRNAs between HPH and control groups were validated by Real‐time quantitative PCR based on the case‐control study ,and receiver operating characteristic curve (ROC ) analysis was used to test the performance of four differentially expressed circulating miRNAs in discriminating HPH and control groups .Results Compared with those in the control group ,13 upregulated miRNAs and 10 downregulated miRNAs were identified in hypobaric hypoxia‐induced HPH rats by using miRNA microarray . And differentially expressed miR‐451 , miR‐505 , let‐7d and miR‐214 were validated by using RT‐PCR .ROC analysis showed that the area under the curve of miR‐451 ,miR‐505 and let‐7d was 0 .979 ,0 .938 and 0 .993 in discriminating HPH and control groups ,respectively .Conclusion The aberrant expression of circulating miR‐451 ,miR‐505 and let‐7d in serum may be correlated with the pathogenesis of HPH .

Changes and significance of endothelin-1 in lung tissue of hypoxic pulmonary hypertension development in neonatal rats / 中华实用儿科临床杂志

Objective To know about the effect and significance of endothelin-1 (ET-1) in pathogenesis of hypoxic pulmonary hypertension(HPH) in neonatal rats.Methods The 120 newborn Wistar rats were randomly divided into hypoxic group and control group,and the rats of hypoxic group were made into HPH model.Mean pulmonary arterial pressure(mPAP) was measured on day 3,5,7,10,14 and 21 after hypoxia.The morphological change of pulmonary vessels were observed,and pulmonary vascular remodeling indexes were also obtained,including the ratio of middle wall thickness to external diameter of small pulmonary arteries (MT％) and the ratio of media cross-section area to total cross-sectional area of small pulmonary arteries(MA％).Immunohistochemistry and Western blot tests were done to determine the expression of ET-1 in lung tissue.Results 1.After hypoxia for 3,5,7,10,14,21 days,the levels of mPAP in hypoxia group[(8.492 ± 1.548) mm Hg,(10.022 ± 1.182) mm Hg,(11.470 ± 2.868) mm Hg,(16.842 ±2.154) mm Hg,(12.824 ± 2.859) mm Hg,(21.036 ± 2.590) mm Hg; 1 mm Hg =0.133 kPa] were significantly higher than those in control group[(5.141 ± 1.022) mm Hg,(8.137 ± 1.057) mm Hg,(8.730 ±0.868) mm Hg,(12.125 ±2.541) mm Hg,(8.920 ±0.744) mm Hg,(11.156 ±1.644) mm Hg] (all P ＜0.05).2.Seven days after hypoxia exposure,small pulmonary arterials remodeling was observed.MT％ [(53 ± 11) ％] and MA％ [(60 ± 9) ％]in hypoxia group were also significantly higher than those in control group [(49 ± 11) ％,(54 ± 8) ％] (all P ＜ 0.05).3.The results of immunohistochemistry:the expression intensities of ET-1 were significantly higher in hypoxia group (0.614,0.613,0.651) after hypoxia for 3,5,7 days than those in control group (0.433,0.386,0.369) (all P ＜ 0.05).4.The results of Western blot:the levels of ET-1 were significantly higher in hypoxia group(4.885 ± 1.391,4.434 ± 1.726,6.309 ± 0.330,2.353 ± 0.961) after hypoxia for 3,5,7 and 10 days than those in control group (1.698 ± 0.794,1.454 ± 0.776,2.045 ± 0.668,0.766 ± 0.515) (all P ＜ 0.05).5.The results of correlation analysis:the total expression of ET-1 protein was positively correlated with the total level of mPAP on 3-7 days after hypoxia (r =0.459,P ＜ 0.05).However,the expression of ET-1 had no significant correlation with MT％ and MA％ (rMT =-0.041,rMA =0.322,all P ＞ 0.05).Conclusions The level of ET-1 in lung tissue of HPH newborn rats increased in the early stage after hypoxia exposure and no longer increased during the late stage,which indicated that hypoxia tolerance prevailed.ET-1 acted as an early reactive marker in the process of HPH development in neonatal rats and may be mainly associated with elevated mPAP,which further prompted that through valid means to inhibit the expression of ET-1 in the early stage of hypoxia,in which the prevention and treatment of this disease may be more effective.

Expression of NO and H_2S in hypoxic pulmonary hypertension and intervention of sodium nitrite in rats / 中国病理生理杂志

AIM:To observe the change of nitric oxide(NO)and hydrogen sulfide(H_2S)in blood and lung homogenate of hypoxic pulmonary hypertension(HPH)rat model,and to discuss the meaning of inhalation sodium nitrite and these factors in the treatment of HPH. METHODS:Fifty healthy male Wistar rats were assigned randomly into 5 groups(10 rats each):normoxia control group(NC),normoxia sodium nitrite group(NNI),hypoxic control group(HC),hypoxic normal saline group(HNS)and hypoxic sodium nitrite group(HNI). The mean pulmonary arterial pressure(mPAP),weight of right ventricle,weight of left ventricle plus septum,and the ratio of the weight of right ventricle to that of left ventricle plus septum(right ventricle hypertrophy index,RVHI)were also determined. The serum level of NO and plasma level of H_2S were measured,and at the same time the levels of NO in the lung homogenate were detected. The structures in pulmonary arteries were examined using optical microscope. RESULTS:After model established,compared to that in the normoxia groups,the body weight decreased significantly in hypoxia groups(P<0.05),although no difference of body weight in five groups before producing model was observed. Compared to that in normoxia groups,the levels of mPAP and RVHI increased significantly in hypoxia groups,and compared to that in hypoxia control groups and hypoxia normal saline group,mPAP and RVHI levels decreased significantly in hypoxia sodium nitrite group(P<0.05). Compared to that in normoxia groups,the serum level of NO decreased significantly in hypoxia groups(P<0.05). NO level in lung homogenate decreased significantly in hypoxia control group and hypoxia normal saline group as compared to that in normoxia groups(P<0.05),and no obvious difference between hypoxic sodium nitrite group and normoxia groups was found. The plasma level of H_2S was decreased significantly in hypoxia groups(P<0.05)as compared to that in normoxia groups. H_2S level increased significantly in hypoxia sodium nitrite group as compared to that in hypoxia control groups and hypoxia normal saline group(P<0.05). Observation under optical microscope,the lumen structure of lung in normoxia control group was normal. No significant change in normoxia sodium nitrite group was found. The proliferation of smooth muscle cells(SMCs),the collagen fiber deposition in the vessel wall and every caliber thickening was observed in hypoxic control group. The same changes were also observed in hypoxic normal saline group. The thickened caliber was relieved significantly in hypoxic nitrite group. CONCLUSION:Pulmonary hypertension and right ventricle reconstitution can be relieved by inhalation of sodium nitrite,and can be regulated by the level of NO and H_2S in rats. Above all,inhalation of sodium nitrite may degrade HPH directly or by affecting the externalization and synthesizing of gas signaling molecule indirectly.

Effects of iptakalim on the mRNA and protein expression of eNOS in pulmonary tissue of chronic hypoxic rats / 中国药理学通报

Aim To study mRNA and protein expression of eNOS in pulmonary tissue of chronic hypoxic pulmonary hypertension(HPH)rats and chronic hypoxic rats treated with novel KATP opener iptakalim.Methods sixty Sprague-Dawley(SD)male rats were randomly divided into control group, hypoxic group, low dose iptakalim group(0.75 mg·kg~(-1)·d~(-1)), and high dose iptakalim group(1.5 mg·kg~(-1)·d~(-1)).Except the first group, the other three groups were put into hypoxic and normobaric chamber (10%±0.5% O_2,8 h/day and 6 day/week) to establish chronic hypoxic model. After four weeks, the mean pulmonary arterial pressure(mPAP), RV/(LV+S)and the plasma concentration of NO were measured. RT-PCR was performed to analyze the mRNA expression of eNOS in pulmonary tissue. Western blot was performed to analyze the protein expression of eNOS, iNOS in pulmonary tissue. Results ① The level of mPAP and RV/ ( LV + S) were significantly higher in the hypoxic group than those in control group ( P < 0. 05 ) , Low dose iptakalim groupandhighdoseiptakalimgroupdecreased the level of mPAP and RV/( LV + S) significantly (P <0. 05). ② The level of NO was significantly lower in the hypoxic group than those in control group (P<0. 05). Low dose iptakalim group and high dose iptakalim group increased the level of NO significantly (P < 0. 05 ). ③ The mRNA and protein expression of eNOS in the hypoxic group were significantly lower than those in the control group (P < 0. 05 ). Low dose iptakalim group and high dose iptakalim group increased the expression of eNOS significantly ( P < 0. 05). High dose iptakalim group was more significant. Conclusion Pulmonary vascular endothelial dysfunction is induced by chronic hypoxia,and the level of NO, the mRNA and protein expression of eNOS are decreased. Iptakalim can improve the vascular endothelial dysfunction, increase the expression of eNOS and the level of NO and reverse hypoxic pulmonary hypertension.

Expression of hypoxia-inducible factor-1? in the lungs of rats with hypoxic pulmonary hypertension / 中国呼吸与危重监护杂志

Objective To study expression of hypoxia inducible factor 1? (HIF 1?) in the lungs of hypoxic rats and to explore the role of HIF 1? in the pathogenesis of hypoxic pulmonary hypertension Methods Twenty Wistar rats were randomly divided into control group and hypoxia group The models of hypoxic pulmonary hypertension were established by exposure to hypoxia for 4 weeks according to our laboratory protocol Digoxin labelled cRNA probe for HIF 1? was prepared by in vitro transcription Northern blot was performed by using the HIF 1? cRNA probe and In situ hybridization was also conducted with rat lung tissue sections Results Northern blot hybridization showed minimally positive in the lung tissue of control group ,but strongly positive in hypoxia group In situ hybridization analysis with hypoxic rat lung tissue revealed that HIF 1? mRNA was expressed in bronchial epithelial cells (strongly positive reaction) and peribronchial proliferative lymphomatic tissue (weakly positive reaction),casually in alveolar wall cells (weakly positive reaction),but not in pulmonary arterial endothelium and smooth muscle cells Conclusions Our data suggested that chronic hypoxia could induce pulmonary hypertension characterized by pulmonary vascular remodeling HIF 1? mRNA expression was elevated in the lungs of rat under hypoxic condition HIF 1 may be involved in the pathophysiological changes in response to hypoxia and play an important role in the development of hypoxic pulmonary hypertension

Effects of ligustrazine on serum CGRP and on the expression of CGRP,PDGF and bFGF in lung of hypoxic rats / 中国药学杂志

OBJECTIVE:To study the effects of ligustrazine on the SCGRP and on the expression of CGRP,PDGF and bFGF in the lung of CHPH rats.METHOD:A stable rat modle of CHPH was established.The serum CGRP levels were mesured by enzyme immunoassay.The expression of CGRP,PDGF and bFGF in lumg were observed by immunohistochemical method.RESULTS:①The SCGRP level of H group was significantly lower than that of N group (P＜0.01) but no difference between the H+Li group and H group (P＞0.05).②The expression of CGRP,PDGF and bFGF increased obviously in lung tissue of H group,whereas the expression of bFGF and PDGF of H+Li group reduced obviously but that of CGRP was not influenced.CONCLUSION:SCGRP reduction and expression increasion increasion of PDGF.bFGF have close relation with the formation of CHPH;Inhibiting the expression of PDGF.bFGF may be an aspect of the mechanism of preventing and treating HPH by ligustrazine.

Hemodynamic Effect of Nitric Oxide Inhalation in the Acute Hypoxic Pulmonary Hypertension Induced Newborn Piglet

Purposes : Nitric oxide (NO) is classified as toxic gas in native states, but in most biologic systems NO acts as a messenger molecule. NO is known as endothelium derived relaxing factor that modulates tone of vascular smooth muscle. Inhaled NO has been reported to act as a selective pulmonary vasodilator and we expect that NO inhalation can be used as a successful treatment modality in the management of persistent pulmonary hypertension of the newborn. We used the newborn piglet to create acute hypoxic pulmonary hypertension and examined the hemodynamic effect of inhlaled NO and dose-response characteristics in different concentrations of NO in this model. The aims of this study were to investigate the feasibility and safety of administering NO to a neonatal model and to get a useful informations about clinical applications of administering NO. METHODS: Nine 2-to 9-d-old piglets with an average weight of 3.1+/-0.86kg were anesthetized, intubated and instrumented in order to measure the hemodynamic variables. NO in nitrogen in a concentration of 800 ppm in 47 liter sylinder was obtained and injected into the inspiratory line of a time-cycled pressure-limited neonatal ventilator after reducing of pressure using 3 staged regulator. Gas mixture in downstream of the injection site was analyzed for NO and NO2 using electrochemical analyzer. Statistical analyses were done using with SAS software ver. 6.04. RESULTS: Baseline hemodynamic parameters in normoxic breathing such as mean systemic arterial pressure, mean pulmonary arterial pressure, systemic vascular resistance, pulmonary vascular resistance and cardiac index were 79+/-18mmHg, 16+/-4mmHg, 0.20+/-0.09mmHg, mL-1, min, kg, 0.04+/-0.02mmHg, mL-1, min, kg, and 399+/-201mL/min/kg respectively. Inhaling 20 and 80 ppm NO during ventilation at FIO2 0.21 did not produce any significant changes in hemodynamic indices. Pulmonary hypertension was induced by reducing the fraction of inspired oxygen to 0.10 to 0.15 and arterial oxygen saturation between 35 and 45%. The hypoxic challenge caused a significant increase in pulmonary arterial pressure, pulmonary vascular resistance and the ratio of pulmonary to systemic vascular resistance of 105% (P<0.001), 92% (P<0.02), 72% (P<0.01) respectively. Systemic arterial pressure increased by 20% (P<0.05), but systemic vascular resistance and cardiac index were not changed significantly. Inhaled NO was then administered in concentrations of 10, 20, 40, 80, and 100 parts per million in random order. All concentrations of NO were associated with a rapid decrease in pulmonary arterial pressure and pulmonary vascular resistance (P<0.02, P<0.001). The ratios of pulmonary to systemic vascular resistance decreased with all levels of inhaled NO (P<0.05). There was no significant difference between the different doses of NO in their effects. There was no significant increase in circulating methemoglobin, and the NO2 levels in the inspiratory limb of ventilator never exceeded 1.5 ppm. Plasma nitrite and nitrate increased in a dose-dependent manner (P<0.05). CONCLUSIONS: In acute hypoxic pulmonary hypertension induced newborn piglets NO inhalation with all the varying concentrations led to reduction of pulmonary arterial pressure promptly and safely without significant increase of methemoglobin and NO2 levels.

Advances in research on the mechanism of hypoxic pulmonary hypertension:role of 15-LO/15-HETE / 中国药理学通报

Hypoxic pulmonary hypertension(HPH) is a common disease featured by acute hypoxic pulmonary vasoconstriction(HPV) and chronic hypoxic pulmonary vascular remolding(HPVR) leading to the sustained increasing of pulmonary artery pressure.There are many mediators involved in the HPH but none can illustrate it successfully.Primary work has found 15-lipoxygenase(15-LO) and its catalyzed production 15-hydroxyeicosatetraenoic acid(15-HETE)(from arachidonic acid) are up-regulated in pulmonary vascular when exprosed to hypoxia.And it has been found 15-LO/15-HETE involved in many processes of both the HPV and HPVR,indicating 15-LO/15-HETE may be an important mediator of HPH.Advances research on 15-LO/15-HETE may illustrate the mechanism of HPH,and will give some message in looking for a potential clinical target of HPH.

Activation of Rho Kinase in Lung Tissue of Hypoxic Pulmonary Hypertension in Rats in Different Stages and Its Significance / 实用儿科临床杂志

Objective To study the expression of Rho kinase and its functional activation in lung tissue from hypoxic pulmonary hypertension(HPH) rat model,and the effects of fasudil on HPH.Methods Seventy-two male Spraque-Dawley rats were randomly divided into the control group,hypoxic model group,and fasudil-intervention group[group with hypoxia and fasudil for 15 mg/(kg?d)],respectively.Mean pulmonary arterial pressure(mPAP) and right ventricle hypertrophy index(RVHI) were measured.Expression of Rho kinase mRNA and protein were examined by reverse transcriptase-polymerase chain reaction(RT-PCR) and Western blot,respectively.The phosphorylation of binding subunit of myosin phosphatase(MBS)-a substrate of Rho kinase was detected by Western blot and defined,as the mark of functional activation of the kinase.Results The expression of Rho kinase mRNA in hypoxic model group was markedly upregulated even before the onset of the third day after the experiment(HPH),and it was much lower in rats of fasudil group than that of hypoxic model group.The phosphorylation of MBS was significantly higher in hypoxic model group than that in control group,and it was positively correlated with the mPAP and RVHI(all P