Role of mechanosensitive ion channel Piezol in mediating phenotypic changes of rat coronary arterial smooth muscle cells induced by high hydrostatic pressure / 中国药理学通报

Aim To investigate the mechanism of Pi- ezol in the phenotypic changes of rat coronary arterial smooth muscle cells ( CASMCs) induced by high hydrostatic pressure.Methods CASMCs were isolated from Wistar rats and stimulated for 24 h at 0, 120 and 180 mmHg, respectively.The expressions of Piezol , contractile phenotvpe-related proteins including Cavl.2 ,SM-MHC ,cx-SMA and synthetic phenotvpe-re- lated proteins including OPN , MMP-2, Coll al were detected by Western blot.The effect of calcium influx mediated by Piezol was detected by Laser confocal mi- j j croscopy.CASMCs were treated with Piezol agonist Yodal , inhibitor GsMTx4 and Piezol-siHNA , respectively and the expressions of contractile phenotvpe and synthetic phenotvpe-related proteins were detected by Western blot.Results Compared with control ( 0 mmHg) , the expressions of Piezol , OPN, MMP-2 and Collal increased, but the expressions of Cavl.2,SM- MHC and cx-SMA decreased in 120 mmHg as well as 180 mmHg group.After stimulated by 180 mmHg high pressure, Piezol-mediated calcium influx was stronger than that in 0 mmHg group, hut decreased after Piezol knockdown.Treated with Yodal at 0 mmHg, the expression of contractile phenotvpe-related protein decreased while the expression of synthetic phenotvpe-re- lated protein increased compared with DMSO group..\Jfter using GsMTx4 to inhibit or siRNA to knockdown Piezol at 180 mmHg,the expression of contractile phe- notvpe-related protein increased and the expression of synthetic phenotype-related protein decreased compared with the control group.Conclusion Piezol promotes the transition from contractile phenotvpe to syn-thetic phenotvpe of CASMCs induced by high hydrostatic pressure.

Advances in research on notch signaling pathway in pulmonary vascular remodeling of pulmonary arterial hypertension / 中国药理学通报

Pulmonary hypertension is a cardiovascular disease characterized by persistent elevation of pulmonary artery pressure and pulmonary vascular resistance, causing pulmonary vascular remodeling. Notch signaling pathway is a highly conserved signaling pathway involved in the occurrence and development of cardiovascular, neurological and tumor diseases mainly by regu-lating cell proliferation, differentiation and apoptosis. TTiis paper mainly reviews the molecular mechanism of Notch signaling path way involved in pulmonary vascular remodeling, contributing to provide a new strategy for the treatment of pulmonary arterial hypertension.

Effects of miR-130a on viability and apoptosis of rat basilar arterial smooth muscle cells / 中国病理生理杂志

AIM:To investigate the regulatory effects of microRNA (miR)-130a on the biological characteris-tics of rat basilar arterial smooth muscle cells (BASMCs) and its underlying mechanisms. METHODS:The expression of miR-130a in rat BASMCs was measured by real-time PCR. After knockdown of miR-130a with inhibitor in the BASMCs, the cell viability, cell cycle distribution and apoptosis were detected by CCK-8 assay and flow cytometry. The expression of cell cycle- and apoptosis-related molecules, such as cyclin D1, cyclin-dependent kinase 2 (CDK2), p21, Bcl-2 and cleaved caspase-3/caspase-3 at protein levels was determined by Western blot. The growth arrest-specific homeobox protein ( Gax) expression at mRNA and protein levels was determined by real-time PCR and Western blot. RESULTS:Angioten-sionⅡ (AngⅡ) up-regulated the expression of miR-130a and down-regulated the expression of Gax (P<0. 05). Transfec-tion with miR-130a inhibitor partly reversed the increase in AngⅡ-induced cell viability and promoted the Gax expression. Furthermore, the early cell apoptotic rate was significantly increased after down-regulation of miR-130a (P<0.05), and the protein levels of cyclin D1, CDK2, Bcl-2 and p-Rb were significantly decreased, accompanied with the up-regulation of p21 and cleaved caspase-3 (P<0.05). CONCLUSION:Down-regulation of miR-130a restrains the viability and pro-motes the apoptosis of BASMCs by promoting Gax expression and regulating cell cycle- and apoptosis-related molecules, suggesting that miR-130a may be a potential therapeutic target of brain vascular remodeling during hypertension.

Effect of xeroderma pigmentosum group D gene on proliferation of hu-man umbilical arterial smooth muscle cells induced by Ox-LDL / 中国病理生理杂志

AIM:To investigate the effects of xeroderma pigmentosum group D ( XPD) gene on the prolifera-tion of human umbilical arterial smooth muscle cells ( HUASMCs) induced by oxidized low-density lipoprotein ( Ox-LDL) . METHODS:The recombinant plasmid pEGFP-N2/XPD was transfected into HUASMCs by liposome .The cells were di-vided into blank control group , pEGFP-N2 group, pEGFP-N2/XPD group, Ox-LDL group, Ox-LDL+pEGFP-N2 group and Ox-LDL+pEGFP-N2/XPD group.The proliferation rate of the cells was detected by MTT and EdU assays .The apop-totic rate and cell cycle distribution were analyzed by flow cytometry .The protein levels of XPD, caspase-3, Bcl-2 and Bax were determined by Western blot .RESULTS:Compared with blank control group , the expression of XPD was increased in pEGFP-N2/XPD group (P<0.05).According to the results of MTT and EdU assays , the cell proliferation in pEGFP-N2/XPD group was reduced compared with blank control group (P<0.05).Compared with Ox-LDL group, the cell prolifera-tion in Ox-LDL+pEGFP-N2/XPD group was significantly inhibited (P<0.05).According to the results of flow cytome-try, the cell proportion of S phase decreased and the G 0/G1-phase cell proportion increased significantly in pEGFP-N2/XPD group and Ox-LDL+pEGFP-N2/XPD group compared with blank control group and Ox-LDL group, repectively (P<0.05).Compared with blank control group and Ox-LDL group, the protein level of Bcl-2 decreased and the protein levels of Bax and cleaved caspase-3 increased in pEGFP-N2/XPD group and Ox-LDL +pEGFP-N2/XPD group, respectively (P<0.05).CONCLUSION:XPD inhibits the proliferation of HUASMCs and promotes their apoptosis , and reduces the promoting effect of Ox-LDL on the proliferation of HUVSMCs .XPD may be the target for treatment of atherosclerosis .

Research progress on role of TGF-β1 in pulmonary artery hypertension / 中国药理学通报

Pulmonary artery hypertension is a disease with complicated pathogenesis, which is characterized by enhanced pulmonary artery constriction and arterial wall remodeling, leading to progressive increase of pulmonary vascular resistance and pulmonary artery pressure, then resulting in right heart failure.Many studies have shown that transforming growth factor-β1(TGF-β1) plays an important role in the development of various diseases, especially in cardiovascular and cerebrovascular diseases.TGF-β1 is involved in multiple cellular responses including cell proliferation, differentiation, migration and apoptosis.TGF-β1 participates in pulmonary artery hypertension mainly via promoting the proliferation of pulmonary artery smooth muscle cells as well as inducing the deposition of extracellular matrix and endothelial-to-mesenchymal transition(EndMT) through many signaling, which is mainly dominated by pulmonary artery smooth muscle cells and pulmonary artery endothelial cells.This review mainly introduces the role of TGF-β1 in pulmonary artery hypertension in order to provide potential drug targets and therapeutic strategies for pulmonary artery hypertension.

Effects of siRNA on EPAS1 activity and proliferation of hypoxic pulmonary artery smooth muscle cells in rats / 解放军医学杂志

Objective This study explored whether EPAS1 gene is involved in the proliferation of pulmonary arterial smooth muscle cells (PASMCs) during hypoxia when EPAS1 gene expression was interfered by small interfering RNA (siRNA).Methods The rat primary pulmonary artery smooth muscle cells were cultured and identified by immunofluorescence.The specific lipidosomes of EPAS1 siRNA were constructed and transfected into PASMCs,and the best targets were selected from the three interfering targets.The transfected PASMCs were cultured in hypoxia (37℃,5％ CO2,2％ O2) or normoxia (37℃,5％ CO2,20％ O2) for 24h,48h and 72h,respectively.The PASMCs proliferation was detected by CCK-8 assay.The protein expression of EPAS 1 and vascular endothelial growth factor (VEGF) were determined by Western blotting to investigate the effect of silencing EPAS1 gene expression on the proliferation of PASMCs under hypoxic condition.Results The specific liposomes ofEPAS1 siRNA were successfully constructed and transfected into PASMCs,and the best interfering target were selected from the three interference targets.The proliferation of PASMCs was increased and the protein expression of VEGF was up-regulated in the PASMCs under hypoxic condition.Under hypoxic or normoxic condition,PASMCs proliferation and VEGF protein expression of PASMCs were suppressed by EPAS 1 siRNA.Conclusion EPAS 1 gene might be involved in the proliferation of rat PASMCs by regulating VEGF protein level under hypoxic condition.

Effect of autophagy inhibitor 3-methyladenine on phenotype transformation and proliferation of pulmonary arterial smooth muscle cells / 实用医学杂志

Objective To evaluate the effect of autophagy inhibitor 3-methyladenine (3-MA) on phenotype transformation and proliferation of rat pulmonary arterial smooth muscle cells (PASMCs).Methods Cultured PASMCs were treated with different concentrations of 3-MA (low-dose group,2.0 mmol/L;middle-dose group,4.0 mmol/L;high-dose group,8.0 mmol/L;control group,0 mmol/L).The protein expression of LC3 Ⅱ,OPN and Vimentin was detected by Western blotting.Cell proliferation was detected by MTT assay.Results The autophagy of PASMCs was decreased with the increase of the concentration of 3-MA.Compared with the control group,significantly down-regulated protein expression of LC3 Ⅱ,OPN and Vimentin was observed in 3-MA-treated cells,with significantly lower proliferation activity.Conclusion The autophagy inhibitor 3-MA significantly down-regulated the expression of LC3 Ⅱ,OPN and Vimentin in PASMCs,with inhibiting the proliferation of PASMCs.

Inactivated Pseudomonas aeruginosa inhibits hypoxia-induced pulmonary hypertension by preventing TGF-beta1/Smad signaling

Pseudomonas aeruginosa is one of the common colonizing bacteria of the human body and is an opportunistic pathogen frequently associated with respiratory infections. Inactivated P. aeruginosa (IPA) have a variety of biological effects against inflammation and allergy. Transforming growth factor-β (TGF-β) signaling plays a critical role in the regulation of cell growth, differentiation, and development in a wide range of biological systems. The present study was designed to investigate the effects of IPA on TGF-β/Smad signaling in vivo, using a hypoxia-induced pulmonary hypertension (PH) rat model. Sprague Dawley rats (n=40) were exposed to 10% oxygen for 21 days to induce PH. At the same time, IPA was administered intravenously from day 1 to day 14. Mean pulmonary artery pressure (mPAP) and the right ventricle (RV) to left ventricle plus the interventricular septum (LV+S) mass ratio were used to evaluate the development of PH. Vessel thickness and density were measured using immunohistochemistry. Primary arterial smooth muscle cells (PASMCs) were isolated and the proliferation of PASMCs was assayed by flow cytometry. The production of TGF-β1 in cultured supernatant of PASMCs was assayed by ELISA. The expression levels of α-smooth muscle actin (α-SMA), TGF-β1 and phospho-Smad 2/3 in PASMCs were assayed by western blot. Our data indicated that IPA attenuated PH, RV hypertrophy and pulmonary vascular remodeling in rats, which was probably mediated by restraining the hypoxia-induced overactive TGF-β1/Smad signaling. In conclusion, IPA is a promising protective treatment in PH due to the inhibiting effects on TGF-β1/Smad 2/3 signaling.

Regulation of autophagy by store-operated calcium channel in arterial smooth muscle cells / 中国药理学通报

Aim To investigate the effect of store-oper-ated calcium channel( SOCC) on autophagy in rat arte-rial smooth muscle cells A7 R5 . Methods Lentiviruses containing STIM1 or Orai1 gene were packaged in 293 T cells and then were used to infect rat arterial smooth muscle cells A7 R5 . The expression levels of STIM1 , Orai1 and Beclin 1 , a critical autophagy-regu-lating protein, of lentivirus-infected A7R5 cells, were detected by Western-blot. Autophagy in lentivirus-in-fected A7 R5 cells was induced by starvation or rapamy-cin, an inhibitor of mammalian target of rapamycin ( mTOR ) . Autophagy marker LC3 of these cells was detected by Western-blot. Results The constructions of vector pLV-STIM1 and pLV-Orai1 were confirmed by restriction enzymes digestion analysis. Compared with the control group, expressions of STIM1 or Orai1 protein was significantly increased after lentivirusLV-STIM1 and LV-Orai1infection, whereas the expressions of autophagy related protein Beclin-1 were down-regu-lated. Starvation or rapamycin stimulated A7R5 auto-phagy but overexpression of STIM1 or Orai1 significant-ly inhibited starvation or rapamycin induced autoph-agy. Conclusion Overexpression of store-operated calcium channel components STIM1 and/or Orai1 in rat arterial smooth muscle cells A7 R5 inhibit autoph-agy. This mechanism might contribute to the develop-ment of pulmonary arterial hypertension.

STIM1 promotes arterial smooth muscle cells proliferation by regulating Akt/mTOR pathway / 中国药理学通报

Aim To investigate the expression of stro-mal interaction molecule 1 (STIM1) in rat pulmonary arterial hypertension ( PAH ) tissues and effects of STIM1 on arterial muscle cells proliferation. Methods PAH was induced by a single intraperitoneal injec-tion of MCT at a dose of 60 mg·kg - 1 . The mRNA or protein expressions of STIM1 in monocrotaline-induced pulmonary hypertensive rats were measured by real-time PCR or Western blot, respectively. The arterial smooth muscle cells A7R5 were transiently transfected with STIM1 plasmids to prepare STIM1 overexpressed cells. Cell proliferations were detected by using CCK-8 kits. The expressions of Akt/ mTOR pathway molecules of A7R5 were measured by Western blot. Results The right ventricular systolic blood pressure ( RVSP) and right ventricular mass index ( RVMI ) were markedly elevated in MCT-treated rats (P < 0. 01) in comparison to control rats. The mRNA and protein ex-pression levels of STIM1 in monocrotaline-induced pul-monary hypertensive rats were 2. 19 and 1. 66 folds of control rats, respectively. STIM1 were transiently over-expressed in cultured A7R5. Cells transfected with STIM1 grew more quickly than non-transfected control. Overexpression of STIM1 significantly increased the phosphorylation of Akt, mTOR, p70-S6K, and 4E-BP1, but did not change their protein expression lev-els. Conclusion STIM1 are over-expressed in rat PAH tissues. Overexpression of STIM1 can promote ar-terial smooth muscle cells proliferation by regulating Akt/ mTOR pathway.

Effect of SKF96365 and NiCl2 on cyclopiazonic acid induced intracellular calcium cation concentration increase in rat distal pulmonary arterial smooth muscle cells / 重庆医学

Objective To study the effect of SKF96365 and NiCl2 on cyclopiazonic acid (CPA) induced intracellular calcium cation concentration ([Ca2+ ]i ) change in rat distal pulmonary arterial smooth muscle cells (PASMC) .Methods The rat distal PASMC were isolated and cultured .The effects of CPA ,SKF96365 and NiCl2 on [Ca2+ ]i in PASMC were tested by fluorescence microscope and InCyte [Ca2+ ]i measurement system .Results PASMC were incubated with Ca2+‐free Krebs solution containing 5μmol/L nifedipine ,10 μmol/L CPA caused a small transient increase in [Ca2+ ]i ;after restoration of extracellular Ca2+ to 2 .5 mmol/L ,10 μmol/L CPA caused marked increases in [Ca2+ ]i in PASMC incubated with Krebs solution containing 5 μmol/L nife‐dipine .Both 50 μmol/L SKF96365 and 500 μmol/L NiCl2 distinctly attenuated the increases in [Ca2+ ]i caused by 10 μmol/L CPA in PASMC .However ,neither 50 μmol/L SKF96365 nor 500 μmol/L NiCl2 affected the increases in [Ca2+ ]i caused by 60 mmol/L KCl in PASMC .Conclusion CPA induced increases in [Ca2+ ]i may related to Ca2+ release from sarcoplasmic reticulum and the in‐flux of Ca2+ through store‐operated Ca2+ channels (SOCC) in rat distal PASMC .Both SKF96365 and NiCl2 could selectively block SOCC and attenuated the influx of Ca2+ through SOCC in PASMC .

Effect of chloride channel blocker on pulmonary hypertension induced by high pulmonary blood flow in rats / 中华实用儿科临床杂志

Objective To study the effect of chloride channel blocker(niflumic acid,NFA) on pulmonary hypertension induced by high pulmonary blood flow in rats.Methods Fifty male or female Sprague-Dawley rats were randomly divided into 5 groups:normal group,sham group,model group,drug 1 group,and drug 2 group,with 10 rats in each group.After subjected to an abdominal aorta-inferior vena cava shunt,all the rats were reared under the same condition for 11 weeks.Then,mean pulmonary artery pressure(mPAP) and right ventricular hypertrophy index(RVHI) of each rat were measured.In addition,arterial wall area/vessel area (W/V) and arterial wall thickness/vessel external diameter(T/D) of each rat were also measured.Results 1.The mPAP of model group [(25.79 ± 4.03) mmHg,1 mmHg =0.133 kPa] was significantly higher than those of normal group [(16.48 ± 1.70) mmHg],sham group [(17.03 ± 2.01) mmHg],drug 1 group [(21.78 ± 2.77) mmHg] and drug 2 group [(20.31 ± 2.15) mmHg] (F =18.983,P ＜0.01).Although the mPAP of drug 1 group was a little higher than drug 2 group,there was no significant difference (P ＞ 0.05).Compared with normal group and sham group,the mPAP of drug 1 group and drug 2 group increased(P ＜0.01,respectively).2.The W/V and T/D of model group were significantly higher than those of normal group,sham group,drug 1 group and drug 2 group (F =26.135,15.527,all P ＜ 0.001).The W/V and T/D of two drug groups showed no significant difference,but they were higher than those of normal group and sham group (P ＜ 0.01,respectively).Conclusions Chloride channel blocker NFA partly decrease mPAP of pulmonary hypertension indnced by high pulmonary blood flow in rats,and inhibit proliferation of vascular smooth muscle cells.These results suggest that NFA had part of therapeutic effect to pulmonary hypertension induced by high pulmonary blood flow.

Role of ERK1/2 and PI3K/PKB signaling pathway in expression of extracellular matrix gene in pulmonary arterial smooth muscle cells in rat / 临床儿科杂志

Objective To explore the effects of the extracellular regulated protein kinase’s (ERK1/2) inhibitor PD98059 and ino-sitol triphosphate kinase (PI3K/PKB) signaling pathway’s inhibitor LY294002 on extracellular matrix (ECM) deposition in pulmonary arterial smooth muscle cells (PASMCs) stimulated by connective tissue growth factor (CTGF). Methods PASMCs of SD rat were cul-tured in vitro. The PASMCs were divided into control group, CTGF group, CP (CTGF+PD98059) group, CL (CTGF+LY294002) group and CPL (CTGF+PD98059+LY294002) group. Real-time lfuorescent quantitative RT-PCR was used to detect the expression of colla-gen III and ifbronectin mRNA of PASMCs, and the expression of collagenШprotein of PASMCs was detected by immunohistochem-istry and western-blot. Results The expressions of collagenШand ifbronectin mRNA of PASMCs stimulated with CTGF (50 ng/ml) for 48 h were signiifcantly higher than those in control group, and the collagen proteinШof PASMCs was decreased signiifcantly after stimulation with CTGF (50 ng/ml) for 72 h (P<0.05). The expressions of collagenШand ifbronectin mRNA in PASMCs cultured with PD98059 (20μmol/L) and/or LY294002 (10μmol/L) for 48 h was signiifcantly lower than those in CTGF group (P<0.05). The collagen proteinШin PASMCs cultured with PD98059 (20μmol/L) and/or LY294002 (10μmol/L) for 72 h was increased (P<0.05). The expres-sions of collagenШand ifbronectin mRNA of PASMCs stimulated with both PD98059 and LY294002 were more signiifcant. Conclu-sions CTGF may increase the expression of collagenШand ifbronectin mRNA in PASMCs, which may contribute to the deposition of ECM in PASMCs during pulmonary vascular remodeling. PD98059 and LY294002 may repress ERK1/2 and PI3K/PKB signaling pathways and interfere with the biological effect of CTGF.

Fluoxetine Protects against Big Endothelin-1 Induced Anti-Apoptosis by Rescuing Kv1.5 Channels in Human Pulmonary Arterial Smooth Muscle Cells

PURPOSE: Pulmonary Kv channels are thought to play a crucial role in the regulation of cell proliferation and apoptosis. Previous studies have shown that fluoxetine upregulated the expression of Kv1.5 and prevented pulmonary arterial hypertension in monocrotaline-induced or hypoxia-induced rats and mice. The current study was designed to test how fluoxetine regulates Kv1.5 channels, subsequently promoting apoptosis in human PASMCs cultured in vitro. MATERIALS AND METHODS: Human PASMCs were incubated with low-serum DMEM, ET-1, and fluoxetine with and without ET-1 separately for 72 h. Then the proliferation, apoptosis, and expression of TRPC1 and Kv1.5 were detected. RESULTS: In the ET-1 induced group, the upregulation of TRPC1 and down regulation of Kv1.5 enhanced proliferation and anti-apoptosis, which was reversed when treated with fluoxetine. The decreased expression of TRPC1 increased the expression of Kv1.5, subsequently inhibiting proliferation while promoting apoptosis. CONCLUSION: The results from the present study suggested that fluoxetine protects against big endothelin-1 induced anti-apoptosis and rescues Kv1.5 channels in human pulmonary arterial smooth muscle cells, potentially by decreasing intracellular concentrations of Ca2+.

Effects of Gax gene transfection on proto-oncogene expression and proliferation of PASMCs in rats under hypoxia conditions / 中国病理生理杂志

AIM:To explore the effects of Gax gene transfection on expressions of c-fos and c-jun mRNA and proliferation of pulmonary arterial smooth muscle cells (PASMCs) in rat under hypoxia. METHODS: PASMCs were transfected with Gax gene by Ad-Gax. Under normal oxygentention (21% O2) or hypoxia (2.5% O2) for 12 h condition, expressions of Gax mRNA and protein in PASMCs were detected by RT-PCR and immunocytochemistry. The expressions of c-fos and c-jun mRNA were evaluated by RT-PCR. [3H]-TdR incorporation was used to measure the PASMCs proliferation. RESULTS: The Gax overexpression in transfection group was confirmed by RT-PCR and immunocytochemistry. Under normal oxygentention or hypoxia, the c-fos and c-jun mRNA levels in transfection group were lower than those in the non-transfection group, respectively (P

Role of K+ channels to resting membrane potential of rabbit middle cerebral arterial smooth muscle cells

The aim of the present study is to investigate the contribution of Ca2+-activated K+ (KCa) channels and delayed rectifier K+ (KV) channels to the resting membrane potential (RMP) in rabbit middle cerebral arterial smooth muscle cells. The RMP and membrane currents were recorded using the whole-cell patch configuration and single KCa channel was recorded using the outside-out patch configuration. Using the pipette solution containing 0.05 mM EGTA, the RMP was -25.76+/-5.08 mV (n=12) and showed spontaneous transient hyperpolarizations (STHPs). The membrane currents showed time- and voltage-dependent outward currents with spontaneous transient outward currents (STOCs). When we recorded the membrane potential using the pipette solution containing 10 mM EGTA, the RMP was depolarized and did not show STHPs. The membrane currents showed no STOCs but only showed slowly inactivating outward currents. External TEA (1 mM) reversibly inhibited the STHPs, depolarized the RMP, reduced the membrane currents, abolished STOCs, and decreased the open probability of single KCa channel. When KV currents were isolated, the application of 4-AP (5 mM) depolarized the RMP. The important aspect of our results is that KCa channel is responsible for the generation of the STHPs in the membrane potential and plays an important role in the regulation of the RMP and KV channel is also responsible for the regulation of the RMP in rabbit middle cerebral arterial smooth muscle cells.

Effect of nitric oxide on transcriptional expression of c-fos and c-jun oncogene of cultured rabbit arterial smooth muscle cells / 中国药学杂志

OBJECTIVE：To study the effcet of Nitric oxide (No) on transcriptional expression of c-fos and c-jun oncogene of cultured rabbit arterial smooth muscle cells (ASMC),and its mechanism.METHODS:(1)To culture rabbit ASMC from explants;(2) To determine if NO,FeSO4,and methylene blue have toxic effect on ASMC by cell counting;(3)RNA isolation from ASMC by Guanidinium Thiocyanate-phenol-chloroform method;(4)RNA-DNA blot hybridization.RESULTS:Under the condition of no toxic effects,NO inhibited the expression of c-fos and c-jun oncogene of ASMC apparently,FeSO4 and methylene blue antagonized the inhibition effcet.CONCLUSION:NO inhibited the expression of c-fos and c-jun oncogene of ASMC through cGMP.This may be related to the important mechanism that NO inhibits the proliferation of ASMC.

Effect of chronic cigarette smoking on BK_(Ca) and Kv1.5 expression in rat pulmonary arterial smooth muscle cells / 中国病理生理杂志

AIM:To investigate the role of potassium channel expression alteration in chronic cigarette smoking-induced increase in pulmonary vascular responsiveness,the effect of chronic cigarette smoking on large-conductance calcium-activated potassium channel(BKCa) and voltage-dependent delayed rectifier potassium channel(Kv1.5) expression in rat pulmonary smooth muscle cells were investigated in vivo.METHODS: HE staining,immuno-histochemistry and in situ hybridization techniques were used.RESULTS:(1) Chronic cigarette smoking downregulates the protein and mRNA expression of BKCa in pulmonary arterial smooth muscles.(2) Chronic cigarette smoking downregulated the protein and mRNA expression of Kv1.5 in pulmonary arterial smooth muscles.(3) In big artery,BKCa decreased more makedly than Kv1.5,but in small artery,both of them decreased equally.CONCLUSION: Chronic cigarette smoking downregulates the levels of BKCa and Kv1.5 in rat pulmonary arterial smooth muscle cells in vivo,which maybe contribute to the mechanism of cigarette smoking-induced increase in pulmonary vascular responsiveness.

EFFECTS OF HCY ON THE EXPRESSION OF HCY-2 AND THE PROLIFERATION IN HUMAN FETUS ARTERIAL SMOOTH MUSCLE CELLS / 解剖学报

Objective To study the homocysteine induced gene(HCY-2) expression in human fetus arterial smooth muscle cells(hASMCs) in culture and explore the effects of homocysteine(HCY) and folic acid on HCY-2 expression and cell proliferation of hASMCs. Methods Immunohistochemistry ABC staining method was used to observe and analyze HCY-2 expression in hASMCs in culture.The image analysis system was used to research of hASMCs quantificationally.The effect of different HCY concentration on the proliferation of hASMCs was investigated by the cell counting. Results Immunoreactive substance of HCY-2 was chiefly found in cytoplasm of hASMCs.The expression of HCY-2 could be affected by HCY concentrations.There was a positive dose-dependent correlation with HCY concentrations in the culture medium.Folic acid increased the expression of HCY-2.The different concentration of HCY enhanced the proliferation of hASMCs,and this enhancement was maximal at the concentration of 1.25 mmol/L of HCY,while the proliferation was decreased when the concentration of HCY was over 1.25 mmol/L.Conclusion HCY increases the expression of HCY-2,and affects the proliferation of hASMCs.HCY is inhibited by folic acid.