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Objective:To explore the predictive value of 18F-FDG PET/CT metabolic parameters combined with inflammatory markers for the medium-term efficacy of chemotherapy in patients with primary gastrointestinal diffuse large B cell lymphoma (PGI-DLBCL). Methods:From April 2011 to May 2020, 67 patients (37 males, 30 females, age: 28-85 years) with PGI-DLBCL examined by 18F-FDG PET/CT before chemotherapy in Changhai Hospital, Navy Medical University were retrospectively analyzed. All patients were treated with cyclophosphamide+ doxorubicin+ vincristine+ prednisone (CHOP) or rituximab+ CHOP (R-CHOP) regimens, and the medium-term efficacy was evaluated after 2-4 cycles of chemotherapy. The effect outcome was divided into complete remission (CR) group and non-CR (NCR) group based on the Lugano lymphoma response evaluation criteria. Mann-Whitney U test was used to compare the differences of SUV max, peak of SUV (SUV peak), metabolic tumor volume (MTV), total lesion glycolysis (TLG), platelet/lymphocyte ratio (PLR) and neutrophil/lymphocyte ratio (NLR) between two groups. The independent risk factors of NCR were analyzed by multivariate logistic regression and the binary logistic regression model was established according to the results. The model was tested with external validation data ( n=15). Results:Of 67 PGI-DLBCL patients, 28(41.8%) were CR and 39(58.2%) were NCR. SUV peak, MTV, TLG, PLR and NLR in NCR group (17.3(12.3, 28.1), 73.8(42.9, 141.7) cm 3, 887.5(300.9, 2 075.3) g, 203.9(155.7, 297.1), 3.9(3.0, 4.9)) were significantly higher than those in CR group (9.5(6.2, 15.2), 11.3(4.7, 23.2) cm 3, 85.2(35.5, 214.6) g, 149.3(102.8, 173.1), 2.2(1.8, 4.6); z values: from -6.41 to -2.33, all P<0.05). The logistic regression model was as follows: P=1/(1+ e - x), x=0.100×MTV+ 0.024×PLR-8.064. The prediction accuracy for NCR risk was 86.57%(58/67), with the accuracy of 13/15 tested by external validation data. Conclusion:MTV combined with PLR has a good predictive value for medium-term efficacy of CHOP/R-CHOP chemotherapy in patients with PGI-DLBCL.
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Objective To investigate the role of high mobility group box 1 (HMGB1) in hepatic endoplasmic reticulum stress (ERS) in rats with trauma. Methods Sixty SPF Sprague-Dawley (SD) rats were randomly divided into groups (n = 6). The rat model of liver injury following traumatic stress was established by continuous compressing the bilateral hind-limbs of rats for 3 hours and then intermittent compressing and decompressing for 30 minutes respectively three times with standard weight of 15 kg. The experiment 1 was divided into two groups: control group and 6, 18, 30 hours after crush. The experiment 2 was divided into control group, crush model group (18 hours after crush), HMGB1 inhibitor sodium butyrate (SB) or ethyl pyruvate (EP) groups, and SB or EP treatment groups (500 mg/kg SB solution or 40 mg/kg EP solution was injected intraperitoneally after 3 hours crush). The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum were measured with automatic biochemistry analyzer. Histopathological severity of liver injury was assessed by hematoxylin and eosin (HE) staining. The expressions of HMGB1 and ERS-related proteins were detected with Western Blot. The expression and translocation of HMGB1 in liver tissue were evaluated by immuno-histochemical technique. Results ① Compared with the control group, the pathological changes of liver injury, the levels of AST and ALT in serum and protein expression of HMGB1 as well as ERS-related proteins such as glucose regulated protein 78 (GRP78), caspase-12, and inositol-requiring enzyme 1α (IRE1α) in liver tissue were significantly increased after traumatic stress, and reached the peak at 18 hours. The expression of C/EBP-homologous protein (CHOP) was increased in a time-dependent manner and peaked at 30 hours after crush. Immunohistochemistry showed that HMGB1 expression increased at 6 hours after crush, some HMGB1 shifted from nucleus to cytoplasm, and the expression was more obvious at 18 hours. ② Compared with crush model group, the expressions of HMGB1 and ERS-related proteins were significantly decreased following the administration of HMGB1 inhibitors SB or EP (HMGB1/β-actin: 0.703±0.213, 0.512±0.075 vs. 1.041±0.186; GRP78/β-actin:0.614±0.052, 0.450±0.115 vs. 0.847±0.120; caspase-12/β-actin: 0.636±0.066, 0.812±0.142 vs. 1.086±0.130;CHOP/β-actin: 0.314±0.046, 0.621±0.123 vs. 0.996±0.764; IRE1α/β-actin: 0.473±0.033, 0.519±0.094 vs. 0.742±0.054, all P < 0.05), the levels of serum AST and ALT were significantly decreased [AST (U/L): 1 030.50±427.73, 1 414.50±347.86 vs. 2 122.20±322.76; ALT (U/L): 285.75±11.30, 368.50±80.58 vs. 473.80±33.54, all P < 0.01], the degree of acute liver injury was reduced. Only SB or EP could not affect the parameters mentioned above. Conclusion HMGB1-ERS pathway was involved in mediating traumatic stress-induced acute liver injury in rats.
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Objective To explore the role of hydrogen sulfide (H 2S ) in acute liver injury induced by crush-ing hind lim bs of rats. Methods The rats w ere random ly divided into the follow ing groups:control, crush-ing, H 2S donor sodium hydrosulfide (NaHS) + crushing, H 2S inhibitor propargylglycine (PAG ) + crush-ing group. The acute liver injury m odel w as established by crushing the hind lim bs of rats w ith standard w eight. R ats w ere sacrificed at 30 m in and 120 m in after the crush. The activities of serum aspartate am inotransferase (AST) and alanine am inotransferase (ALT) w ere m easured by colorim etric m ethod, and the content of H 2S in plasm a and the contents of m alondialdehyde (MDA), protein carbonyl, glutathione (GSH) in the liver and the activity of H 2S generating enzym e (cystathionine γ-lyase, CSE) w ere deter-m ined by chem ical m ethod. The expression of CSEm R N Ain liver w as detected by R T-PCR . Results For crush injury group, the levels of ASTand ALTin serum , MDAand protein carbonyl in liver in-creased. The levels of GSH, CSE, CSEm R N Ain liver and H 2S in serum decreased. The adm inistration of NaHS before lim bs crush could attenuate the changes of liver injury, but the pre-treatm ent w ith PAG could exacerbate the changes. Conclusion The decrease of H 2S production could involve in m ediating the acute liver injury induced by traum atic stress in rats.
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Objective To investigate effects of antioxidant stress protein hem e oxygenase-1 (HO-1) on lipopolysaccharide (LPS)-induced endoplasm ic reticulum stress (ERS) of rat hepatocytes. Methods The BRL cells (rat hepatocyte cell line) were cultured. The hepatocytes were treated with LPS, LPS+HO-1 si RNA , HO-1 siRNA and PB S solution, respectively. The cell viability was m easured by trypan blue ex-clusion test. The apoptosis cells were detected by the fluorescent dye Hoechst 33258. E xpressions of GR P78, C HO P, caspase-12 and HO-1 were detected by Western blotting. Results LPS caused an in-crease of HO-1 protein expression of rat hepatocytes in a dose-dependent and tim e-dependent m anner, a up-regulation of GRP78, CHO P and caspase-12, a decrease in cellviability,and an increase in apopto-sis rate of hepatocytes. Pretreatm ent of HO-1 siRNA inhibited the up-regulation of LPS-induced HO-1, however, aggravated ERS and cellular injury. Conclusion HO-1 inhibites ERS-m ediated cellular injury of rat hepatocytes induced by LPS.
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Objective To observe the time-course expression of calcium-calmodulin dependent protein ki-naseⅡδ (CaMKⅡδ) in cerebral cortex after traumatic brain injury (TBI). Methods The TBI rat model was established. The expression of CaMKⅡδ in cerebral cortex around injured area was tested by Western blotting and immunohistochemical staining . Results Western blotting revealed expression of CaMKⅡδ in normal rat brain cortex. It gradually increased after TBI, peaked after 3 days, and then returned to normal level. The result of immunohistochemical staining was consistent with that of West-ern blotting. Conclusion The expression of CaMKⅡδ around injured area after TBI increased initially and then decreased. It could be used as a new indicator for wound age determination following TBI.
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In practice of forensic medicine, potential disease can be associated with fatal asphyxia in re-straint position. Research has demonstrated that nitric oxide (NO) and nitric oxide synthase (NOS) are plentifully distributed in skeletal muscle, contributing to the regulation of contractile and relaxation. In the current study, respiratory functions, indices of diaphragmatic biomechanical functions ex vivo, as well as NO levels in serum, the expressions of diaphragmatic inducible NOS (iNOS) mRNA, and the effects of L-NNA on contractility of the diaphragm were observed in sepsis induced by cecal ligation and punc-ture (CLP) under the condition of restraint position. The results showed that in the CLP12-18 h rats, respiratory dysfunctions; indices of diaphragmatic biomechanical functions (Pt, +dT/dtmax, -dT/dtmax, CT, Po, force over the full range of the force-frequency relationship and fatigue resistance ) declined progressive-ly; the NO level in serum, and iNOS mRNA expression in the diaphragm increased progressively; force increased significantly at all stimulation frequencies after L-NNA pre-incubation. Restraint position 1 h in CLP12 h rats resulted in severe respiratory dysfunctions after relative stable respiratory functions, almost all the indices of diaphragmatic biomechanical functions declined further, whereas little change took place in NO level in serum and diaphragmatic iNOS mRNA expression; and the effects of L-NNA were lack of statistical significance compared with those of CLP12 h, but differed from CLP18 h group. These results suggest that restraint position and sepsis act together in a synergistic manner to aggravate the great reduction of diaphragmatic contractility via, at least in part, the negative modulation of NO, which may contribute to the pathogenesis of positional asphyxia.
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Our previous experiments confirmed that endothelial derived ONOO- mediated injury to cultured BPAEC induced by LPS, and that CCK protected endothelial functions against the detrimental effect of LPS in vitro. In the present study, using cultured BPAEC, we investigated effect of CCK on LPS-induced generation of ONOO- in BPAEC and on injury to BPAEC induced by LPS. Results were as follows.(1)CCK inhibited increase in endothelial generation of ONOO- induced by LPS, for fluorescent intensity of NT in BPAEC reduced from (6.55±0.30) AU of LPS group to (4.37±0.08) AU (P＜0.01), the latter being still higher than (3.27±0.15) AU of vehicle group (P＜0.01). In contrast, the number and percentage of NT positive cells reduced a little. Proglumide, a nonspecific inhibitor of CCK receptors, might in part reverse the effect of CCK. (2)CCK markedly reduced MDA content in supernatant in LPS group (P＜0.01), which was completely reversed by proglumide(P＜0.01). Activities of LDH in supernatant in LPS, LPS+CCK group were (85.30±8.66) U/L and (71.33±4.07) U/L, respectively. Proglumide elicited increase in activity of LDH ［(81.00±6.35) U/L］. However, effect of CCK or proglumide was not significant in the alterations of activity of LDH. (3)CCK significantly inhibited increase in apoptotic rate in BPAEC induced by LPS, from 13.50%±0.60% of LPS group to 5.35%±0.25%(P＜0.001), the latter being completely reversed by proglumide with apoptotic rate of 11.45%±0.65%(P＜0.05).These results further confirmed that CCK afforded the cyoprotection for the mitigation lipoperoxide damage and inhibition of apoptosis in BPAEC induced by LPS. The cytoprotection of CCK may be mediated by CCK receptors and related to the reductive ability of endothelia to generate ONOO- induced by LPS.
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In this study we found: 1\, There was endogenous ONOO- formation in lungs in the early stage of endotoxic shock. Exogenous ONOO- led to increase in microvascular permeability, severe lung pathological changes and enhanced MDA content. 2\, It was, for the first time, found that responses of isolated pulmonary artery preincubated with ONOO- showed abnormal manifestations. (1) Low dose of ONOO- let to the inhibition of endothelial dependent relaxation, but enhacement of contractile response, both of which were similar to changes of reactivity in isolated pulmonary artery induced by LPS. (2) High dose of ONOO- reduced contractile response to PE and relaxation to SNP. 3\, ONOO- had direct effect for relaxation of precontracted isolated pulmonary artery. The relaxing action of ONOO- was weak and was negtively regulated by endothelial cells, supporting the notion that ONOO- may be involved in pulmonary hypertension in the early stage of endotoxic shock. 4\, It was, for the first time, found that LPS-induced increase in endogenous ONOO- generation in BPAEC and that endogenous ONOO- mediated injury to BPAEC induced by LPS, which may be a novel mechanism for endotoxin-elicited damage to endothelial cells. 5\, Exposure of pulmonary artery to LPS led to reduction in endothelial dependent relaxation but enhancement in contractile response, both of which were reversed by concomitant exposure to CCK and LPS. 6\, CCK protected cultured BPAEC against the detrimental effects of LPS such as lipoperoxide damages and cellular apoptosis as well as LPS-induced endogenous ONOO- formation. The underlying mechanism of CCK for cytoprotection may be mediated by its receptors and related to its reduced ability of endothelia to generate ONOO- induced by LPS.
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This study was designed to invesigate vasodilatory action of exogenous peroxynitrite (ONOO-), and effect of endothelial cells on ONOO- -induced relaxation in isolated rabbit pulmonary arterial rings (PARs). Results were as follows: (1) In precontracted PARs, ONOO- could give rise to vasodilation in a dose-dependent manner. Relaxations of PARs to ONOO- at doses of 10-5 mol/L, 5×10-5 mmol/L and 10-4 mol/L were 11.09%±1.84%, 31.10%±3.53% and 64.35%±3.83%, respectively, all of which were significantly higher than those of decomposed ONOO- with 5.88%±1.27%、16.15%±1.82% and 34.44%±3.26% at same concentrations, respectively. (2) Compared with SNP and ACh, ONOO- had weak relaxant action. (3) ONOO- induced more significantly enhanced relaxation in denuded endothelial PARs than in intact endothelial PARs. (4) In this experimental condition, the relaxation of PARs to 10-6 mol/L ACh remained unchanged before and after observation of relaxation to ONOO-. (5) The relaxations of PARs to 5×10-5 mol/L ONOO- in repetitively administered manner appeared progressively decreased. These results suggested that ONOO- might be implicated in pulmonary hypertension in the early stage of endotoxic shock.
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AIM:To investigate the pathologic changes in the brain and its underlying mechansims during ischemia-reperfusion of rat hindlimbs.METHODS:SD rats were divided into the normal(N), sham(S), 4 h ischemia without reperfusion(I), and 4 h ischemia-2, 6,12,18 or 24 h reperfusion (I-R) groups at random. Ischemia and ischemia-reperfusion were established with the occlusion or/and re-opening of the terminal of abdominal aorta, respectively. The pathologic changes in the brain tissue were morphologically observed. The expression of inducible nitric oxide synthase (iNOS) mRNA, and iNOS protein and the nitrotyrosine, a marker of peroxynitrite (ONOO-)，in the brain tissue were detected with RT-PCR and immunohistochemical technique, respectively. The brain superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents were spectraphotometrically measured.RESULTS:Hydropic degeneration and severe injury to neurons were only showed in I-R group. Expressions of iNOS mRNA and protein were demonstrated in I-R, I and S groups, which were maximal in I-R 6 h group. iNOS positive neurons and microglias were more spread in I-R 6 h group than those in S and I groups. NT positive neurons were localized in the cerebral cortex and hippcampus of I-R 6 h group. The contents of MDA markedly increased, while the activity of SOD significantly decreased in I-R 6 h group compared to the N, S and I groups. There were no significant changes in MDA and SOD in N, S and I groups.CONCLUSION:Severe ischemia-reperfusion of rat hindlimbs could induce brain injury, and its mechanisms might be related to enhanced expression of iNOS-NO-ONOO- in the brain.
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AIM:To study the effect of ONOO- on the airway epithelial injury. METHODS: The mitochondrial respiration, the amount of lactate dedydrogenase (LDH) release into the cell culture medium, the levels of 8-hydroxy-2′-deoxyguanosine (8-OHdG), and the cellular apoptosis were examined after exposure of cultured rat tracheal epithelial (RTE) cells to ONOO-. RESULTS: Exposure of RTE cells to 0.25, 0.5 and 1 mmol/L ONOO- caused a dose-dependent suppression of the mitochondrial respiration . ONOO- also caused a dose-dependent increase in the percentage of LDH release. Exposure of RTE cells to ONOO- resulted in an increased generation of 8-OHdG in a dose-dependent manner. ONOO- caused an increase in apoptotic percentage in RTE cells in a time-dependent manner at different concentrations. CONCLUSION: ONOO- could cause necrosis and apoptosis in cultured RTE cells. Low concentration of ONOO- caused apoptosis in a time-dependent manner. Whereas exposure to high concentration of ONOO- resulted in cell necrosis, ONOO- caused a dose-dependent increase in the percentage of LDH release. Suppression of mitochondrial respiration and oxidative DNA damage by ONOO- may be the major cause of cellular injury induced by ONOO-.
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This experiment, using cultured bovine pulmonary artery endothelial cells (BPAEC), was undertaken to investigate roles of endogenous ONOO- in lipopolysaccharide (LPS)-caused injury to endothelial cells. The fluorescent intensity of nitrotyrosine (NT), a marker of ONOO- generation, in BPAEC represented content of endogenous ONOO- generation. The fluorescent intensity of NT and number of NT positive cells were detected with flow cytometry, and the percentage of NT positive cells was calculated. Results were as follows. (1) LPS (1 mg/L, 5 mg/L and 10 mg/L) caused marked increase in fluorescent intensity of NT in a dose dependent manner. The number and percentage of NT positive cells were markedly increased (P＜0.05). Aminoguanidine (AG), a selective inhibitor of inducible nitric oxide synthase, inhibited the increase in fluorescent intensity of NT in BPAEC induced by LPS. However, the number and percentage of NT positive cells had tendency to reduce. (2) LPS caused the enhancement of MDA content and activity of LDH in cultured supernatant (P＜0.01). AG reversed the enhancement of MDA content induced by LPS (P＜0.01). In contrast, AG had marginal effect on activity of LDH. (3) LPS induced the increase in apoptotic rate in BPAEC in a dose dependent manner. Some BPAEC stained with fluorescent probe ethidium bromide showed morphological features of apoptosis with chromatin condensation and nuclear fragmentation. AG reduced the apoptotic rate and number of apoptotic cells, both of which were still higher than those of vehicle group (P＜0.05). (4) LPS inhibited mitochondrial respiration. Effect of LPS on mitochondrial membrane potential (ΔΨ) depended on the doses of LPS. 1 mg/L LPS led to a little increase in ΔΨ, while 5 mg/L and 10 mg/L LPS significantly reduced ΔΨ. In conclusion, LPS caused injury to cultured BPAEC and increased production of ONOO-. Cytotoxicity of LPS may be mediated by endogenous ONOO-.
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In order to investigate the possible role of ONOO- in regulatory disorder of pulmonary arterial tension in endotoxic shock, the responses of rabbit pulmonary arterial rings (PARs) preincubated with ONOO- to endothelial dependent and receptor dependent relaxants acetylcholine (ACh) and adenosine diphosphate (ADP), endothelial dependent and receptor independent relaxant A23187, endothelial independent relaxant sodium nitroprusside (SNP) and α1-adrenoceptor agonist phenylephrine (PE) were observed in vitro in accumulative manner. Results were as follow: (1) Relaxations of PARs to ACh, A23187 and ADP were markedly impaired with shift of accumulative dose response curve of each agonist to the right. Inhibition of endothelial dependent and receptor dependent or independent relaxation by ONOO- was dose dependent. (2) ONOO- incubation inhibited SNP-induced relaxation in a dose dependent manner. Accumulative dose response curve of SNP was right shift to some degree depending on the doses of ONOO-. (3) Contractile response of PARs to PE varied with the different doses of ONOO-. In PARs preincubated with 0.5 mmol/L ONOO-, contractile reponse was significantly enhanced with shift of PE accumulative dose response curve to the left, while in PARs preincubated with 1.0 mmol/L or 2.0 mmol/L ONOO-, it was markedly reduced with right shift of PE accumulative dose response curve. (4) Vehicle of ONOO- had no effect on responses to every agonist, whereas decomposed ONOO- had minimal effect on the response to PE and ADP. In contrast, relaxation of PARs to ACh, A23187 and SNP were enhanced. These results suggested that direct effect of ONOO- on pulmonary artery may be a key factor contributing to regulatory disorder of pulmonary arterial tension induced by LPS and pulmonary hypertension in the early stage of endotoxic shock.
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AIM：The mechanism of tumor necrosis factor-alpha (TNF-α) induced pulmonary artery hypertension(PAH) in endotoxic shock (ES) is not clear. Cholecystokinin-octapeptide (CCK-8) had anti-ES and anti-PAH effects. The impact of CCK-8 on changes in vascular reactivity and endothelial ultrastructure induced by TNF-α was studied. The role of nitric oxide (NO) was preliminarily studied. METHODS：Rabbit pulmonary artery rings were divided into four groups: TNF-α, TNF-α+CCK-8, CCK-8 and Vehicle. The rings were incubated for 2 h, 7 h or 14 h. Relaxative responses to ACh(10-8-10-5 mol/L)， SNP (10-9-10-6 mol/L) and contractile responses to PE(10-8-10-5 mol/L) were generated seperately. The NOS activity of rings was detected and the ultrastructure of endothelium was observed in the groups that incubated for 7 h.RESULTS:The relaxative responses to ACh were not affected by TNF-α and CCK-8 after incubation for 2 h. TNF-α(7 h,14 h) significantly reduced ACh-induced endothelium-dependent relaxation response of pulmonary artery. CCK-8 reversed the effect. CCK-8 itself had no effect on responses of normal pulmonary artery. Contraction to PE and relaxation to SNP were unaffected by TNF-α, CCK-8. The NOS activity increased in the TNF-α and the TNF-α+CCK-8 groups. While no significant difference was obseved between the Vehicle and the CCK-8 groups. Endothelial injury in TNF-α group and alleviated changes in TNF-α+CCK-8 group were observed. CONCLUSION:TNF-α significantly inhibits endothelium-dependent relaxation, which be one of the mechanisms of PAH induced by TNF-α during ES. It was found for the first time that CCK-8 reversed TNF-α induced impairment of endothelium-dependent relaxation and alleviated structural injury of endothelium, which might be one of the mechanisms of anti-PAH effect by CCK-8 during ES. The effects of TNF-α and CCK-8 might be related to NO.
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AIM: To investigate the inhibitory effects of cholecystokinin octapeptide(CCK-8) on nuclear factor-?B(NF-?B) activities stimulated by lipopolysaccharide(LPS) by using forskolin,the activator of adenylate cyclase,and PKA inhibitor H-89 in rat pulmonary interstitial macrophages(PIMs).METHODS: PIMs were isolated and purified.EMDA was applied to detect NF-?B activities and Western blotting was used to analyze the I?B-? protein level in rat PIMs.RESULTS: The NF-?B activity was not detected in normal control rat PIMs.The NF-?B activity in LPS-treated rat PIMs was obviously higher than that in control group(P0.05).The NF-?B activity in CCK+LPS group and LPS+Fsk group were obviously lower than that in LPS group(P
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AIM: To investigate the effect of cholecystokinin octapeptide(CCK-8) on the L-arginine-nitric oxide(NO) pathway in rabbit thoracic aortae treated with lipopolysaccharide(LPS). METHODS: The isolated thoracic aortic rings(TARs) from rabbits were incubated with LPS, LPS+CCK or vehicle for 14 h. Then the contractility to phenylephrine(PE) by TARs and the response to L-arginine(L-Arg) by pre-contractile TARs were measured. In addition, we added NO synthase(NOS) inhibitors aminoguanidine(AG)and N ?-nitro-L-arginine(L-NNA) into organ baths to observe the changes of vascular contractility to PE. NOS activity in isolated TARs were also detected. RESULTS: Incubation of TARs with LPS for 14 h resulted in an increase of NOS activity and a reduction of contractility to PE. Treatment with CCK-8 significantly inhibited the increased NOS activity in thoracic aortae and improved the hypocontractility of TARs to the same degree as AG. CONCLUSION: CCK-8 may improve the hypocontractility of TARs induced by LPS by inhibiting the activity of NOS.
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AIM and METHODS: To elucidate the mechanism of anti-endotoxic shock of cholecystokinin octapeptide(CCK-8), the effects of CCK-8 on changes in rabbit thoracic aortic reactivities induced by lipopolysaccharides(LPS) in vitro were studied, and the ultrastructure of the endothelial cells was observed under scanning electron microscope. RESULTS: Incubation of thoracic aortic rings(TARs) with LPS(100 mg/L) resulted in an time-dependent impairment of the endothelium-dependent relaxations to acetylcholine(incubation for 3, 7, 14 h), a reduction of contractive response to phenylphrine(incubation for 14 h) and ultrastructural injury in endothelial cells(incubation for 7 h), all of which were alleviated by concomitant incubation with CCK-8(1 mg/L). In contrast, neither the vascular contractions nor the relaxations were affected by CCK-8 (1 mg/L) alone. CONCLUSION: CCK-8 improved the vascular reactivities in the presence of LPS, which may be one of the anti-endotoxic shock mechanisms of CCK.
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AIM: To explore the effect of peroxynitrite (ONOO -) on pulmonary microvascular endothelial barrier and roles of ONOO - in the pathogenesis of acute lung injury in vivo. METHODS: SD rats in different groups were insufflated with various concentrations of ONOO -, decomposed ONOO - or vehicle (alkaline normal saline), respectively. Then permeability changes in pulmonary microvascular walls were detected and the pathological alterations of pulmonary tissue were examined under light microscope. Malondialdehyde(MDA) contents were measured in normal lung homogenate pretreated with various concentration of ONOO -. RESULTS: Intratracheal insufflation of ONOO - resulted in dose-dependent increase in lung coefficient, lung wet/dry ratio, lung water contents and Evans blue contents, together with significant pulmonary pathological changes such as diffuse alveolar collapse, capillary congestion, focal hemorrhage, and endothelial swollen. In addition, ONOO - can also elicit increase in MDA contents in normal lung homogenate. CONCLUSION: ONOO - may induce dysfunctions of pulmonary microvascular endothelial barriers, it is suggested that enhanced endogenous ONOO - generation may take part in the pathogenesis of acute lung injury.
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AIM: To investigate the pathologic changes in the brain and its underlying mechansims during ischemia-reperfusion of rat hindlimbs.METHODS: SD rats were divided into the normal(N), sham(S), 4 h ischemia without reperfusion(I), and 4 h ischemia-2, 6,12,18 or 24 h reperfusion (I-R) groups at random. Ischemia and ischemia-reperfusion were established with the occlusion or/and re-opening of the terminal of abdominal aorta, respectively. The pathologic changes in the brain tissue were morphologically observed. The expression of inducible nitric oxide synthase ( iNOS ) mRNA, and iNOS protein and the nitrotyrosine, a marker of peroxynitrite (ONOO -),in the brain tissue were detected with RT-PCR and immunohistochemical technique, respectively. The brain superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents were spectraphotometrically measured.RESULTS: Hydropic degeneration and severe injury to neurons were only showed in I-R group. Expressions of iNOS mRNA and protein were demonstrated in I-R, I and S groups, which were maximal in I-R 6 h group. iNOS positive neurons and microglias were more spread in I-R 6 h group than those in S and I groups. NT positive neurons were localized in the cerebral cortex and hippcampus of I-R 6 h group. The contents of MDA markedly increased, while the activity of SOD significantly decreased in I-R 6 h group compared to the N, S and I groups. There were no significant changes in MDA and SOD in N, S and I groups.CONCLUSION: Severe ischemia-reperfusion of rat hindlimbs could induce brain injury, and its mechanisms might be related to enhanced expression of iNOS -NO-ONOO - in the brain.
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AIM: To study the changes of iNOS mRNA ,protein and the production of nitric oxide(NO) as well as whether puerarin regulates the expression of iNOS mRNA during the formation of diabetic rat cataract. METHODS: One hundred and eight Sprague-Dawley(SD) rats were randomly divided into three groups, thirty-six rats were taken as control group, seventy two rats were injected peritoneally with streptozotocin(STZ,45mg/kg) to establish animal model of diabetic cataract, and then divided into STZ (36) and puerarin(36) treatment groups. Morphologic changes of lens were observered with slit lamp and light microscope; Samples were taken at 20th, 40th, 60th day and the changes in iNOS mRNA and protein expression of lens epithelium cells(LEC)as well as production of NO and NOS activity were determined with reverse transcription -polymerase chain reaction(RT-PCR), western blot, and biochemical method ,respectively. RESULTS: Morphologyic changes of LEC, up-regulation of iNOS mRNA and iNOS protein as well as increase in NO production and NOS activity in the LEC were observered during the formation of rat diabetic cataract. Compared with TZ group, puerarin treatment group showed distinctly down-regulation of iNOS mRNA and iNOS protein and decrease in NO production and NOS activity as well as attenuation of morphologic changes. CONCLUSIONS: There are morphologic changes of LEC and up-regulation of iNOS mRNA and as well as increase in NO production and NOS activity in the LEC during the formation of diabetic rat cataract , and treatment with puerarin can reverse the above changes.