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Objective:To analyze the relationship between plasma level of cortistatin(CST) and coronary heart disease(CHD) and the factors that influence the level of CST.Methods: Plasma levels of CST were measured using ELISA method.The clinical data and the levels of CST of 40 healthy subjects and 39 CHD patients before and 1 d after percutaneous coronary intervention(PCI) were compared.And the factors that influenced the CST level were analyzed.Results: The CST levels of CHD group before or 1 d after PCI were significantly higher than those of the control group(1.97?1.12 and 2.01?0.77 vs 1.21?0.27,P0.05);There was no correlation between CST levels and fasting blood glucose(FBG),high sensitivity C-reactive protein(hsCRP),left ventricular ejection fraction(LVEF),severity of lesions of coronary arteries or history of hypertension;The levels of triglyceride(TG) and total cholesterol(TCHOL) negatively correlated with CST levels(?=-2.594,P
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Objective: To determine the role of cross-talk between calcineurin-dependent signal transduction pathway and protein kinase C (PKC), mitogen-activated protein kinase (MAPK) and protein kinase A (PKA) in airway remodeling in asthma. Methods: Male guinea pigs were sensitized with intraperitoneal injections of ovabumin (OVA), then treated with cyclosporin A (CsA,5 mg/kg), an inhibitor of calcineurin, then inhaled OVA for 2 weeks 14 days later. Activities of calcineurin, PKC, MAPK, and PKA were was analyzed by phosphorylation and dephosphorylation. In primary cultures of rat airway smooth muscle cells (ASMC), activities of calcineurin, PKC, MAPK, and cross-talk induced by urotensin Ⅱ (UⅡ), a recently identified strong mitogen, were measured. Results: (1) The activities of calcineurin, MAPK and PKC increased by 19% (P0.05). (4) CsA 10 -6 mol/L inhibited UⅡ-stimulated PKC activity by 14% (P0.05). Conclusion:The signal transduction pathways between calcineurin and other protein kinases such as PKC, MAPK and PKA have cross-talk in airway remodeling in asthma.
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AIM To investigate effect of urotensin Ⅱ (UⅡ)on proliferation of aort a smooth muscle cells （ASMC）of rat and study the signal transduction pathway o f it. METHODS In cultured ASMC of rat, UⅡ was used to stimulate proliferation of these cells and levels of ［3H］-TdR incorporation were used to evaluate the speed of DNA synthesis, and different inhibitors were used to s tudy the action of different signal transduction pathway of mitogenic effect of UⅡ on VSMC. RESULTS 1×10-9～1×10-7 mol*L- 1 UⅡ caused marked concentration-dependent increasing of ［3H］-TdR i ncor poration of ASMC. ［3H］-TdR incorporation of 1×10-9,1×10-8 and 1×10-7 mol*L-1 UⅡ were 22%（P<0.05）, 57%（P<0.01）and 65%（P<0.01）higher than control. Nicardipine, H7, W7 and PD98059 , which are inhibitors of calcium channel, PKC, CaM-PK and MAPK respectively, inhibited the effects of UⅡ obviously, with the inhibitory rate by 55%（P< 0.01）, 27%（P<0.01）,18%（P<0.05）and 16%（P<0.05）respectively . CONCLUSION UⅡ is a strong mitogen for VSMC and the mitogenic e ffect of UⅡ is probably mediated by Ca2+, PKC, CaM-PK and MAPK signal tr ansduction pathway.
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Objective: To study the effect of urotensin(U Ⅱ) on nitric oxide synthase(NOS)/nitric oxide(NO) system in rat aorta. Methods: The aortic slices were incubated in vitro. The medium nitrite content, vascular NOS activities and cGMP content were measured. Results: After incubation of aorta for 1.5－3.0 h, UⅡ(10－9－10－7 mol*L－1) increased nitrite production ( 14.8%－80.9%, P<0.01) in dose-dependent manner. U Ⅱ significantly stimulated the total NOS activities, mainly activated constitutive NOS (P<0.05 or P<0.01), however, the inducible NOS activities were not altered (P>0.05). Incubation of aortic slices with U Ⅱ (10－9－10－7 mol*L－1) increased vascular cGMP content in dose-dependent manner. Co-incubation vascular tissue with U Ⅱ and GN-L-nitro-arginine, an inhibitor of NOS, obviously inhibited the U Ⅱ-induced NOS activation, NO production and cGMP formation. Conclusion: The results suggest that U Ⅱ can activate the vascular NOS/NO pathway, increasing tissue NO production and cGMP content.
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AIM: To investigate the effect of endothelin (ET), angiotensin II (AngII) and homocysteine (Hcy) on C-type natriuretic peptide (CNP) synthesis and release. METHODS: Human endothelial cell was cultured; CNP was measured by radioimmunoassay method. RESULTS: ET and AngII could augment CNP synthesis in human endothelial cells. Compared with control group, 10-9,10-8,10-7 mol/L ET and Ang II increased CNP content of endothelial cells by 1%(P＞0.05), 49%(P＜0.05),117%(P＜0.01) and 137% (P＜0.01),165%(P＜0.01),201%(P＜0.01),respectively. A great dose of ET and Ang II also stimulated CNP release from cultured human endothelial cells. Hcy had no effect on CNP synthesis, but 10-9，10-8,10-7 mol/L Hcy enhanced CNP release from cultured human endothelial cells by 17%(P＞0.05),84%(P＜0.01) and 555%(P＜0.01), respectively. CONCLUSION: ET, AngII and Hcy might be involved in the synthesis and release of human endothelial cell CNP.
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AIM:To study lipopolysaccharide (LPS)-stimulated secretion of endothelin-1 (ET-1) and adrenomedullin (Adm) from human vascular endothelial cells (HVEC) and its mechanism. METHODS:In cultured HVEC, LPS was used to stimulate ET-1 and Adm secretion from HVEC. The contents of ET-1 and Adm in medium were determined by radioimmunoassay. RESULTS:LPS stimulated secretion of ET-1 and Adm from HVEC in time-dependent and concentration-dependent manner. The ratio of secreted ET-1 to Adm was not changed compared with the control group. The increase of ET-1 could be inhibited by inhibitor of extracellular signal-regulated protein kinases (PD098059) and inhibitor of P38 kinase (SB202190)（P＜0.01）, while the increase of Adm could only be inhibited by SB202190（P＜0.05）, both had no response to inhibitor of protein kinase C (H7), inhibitor of calmodulin (W7), inhibitor of calcineurin (cyclosporin A) and inhibitor of Ca2+ (nicardipine)（P＞0.05）.CONCLUSION:ERKs and P38 signal pathways may play an important role in the secretion of ET-1 from LPS -stimulated HVEC, while only P38 kinase signal pathway is invovled in the secretion of Adm.
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AIM: To investigate the activity and distribution of calcineurin (CaN) in different tissues of rat. METHODS: Using western blot and immunohistochemical staining methods to measure the amount and location of CnA?, isoform of catalytic subunit of CaN in different tissues of rat. CaN activity was measured by labelled substrate peptide. RESULTS: 1. Western blot showed that CnA? expression was detected in brain, heart, skeletal muscle and lung tissues. There was no detectable CnA? expression in kidney and aorta. 2. In immunohistochemical staining study, there was strong immunostaining of CnA? in brain. CnA? was located in cytoplasm of cardiac cell, macrophage and connective tissue of peribronchiolar in lung tissue, aorta adventitia, connective tissue around small vessels and outer wall of renal tube. 3. CaN activity was highest in brain, the following was skeletal muscle, myocardium and lung tissue. CaN activity was lowest in aorta and kidney tissue. CONCLUSION: CaN is widely distributed in rats and might be involved in functional regulation of various organs and tissues.
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AIM: To investigate the effect of basic fibroblast growth factor (bFGF) on C-type natriuretic peptide (CNP) production, release and mRNA expression. METHODS: Human endothelial cell cultured; CNP was measured by radioimmunoassay method;CNP mRNA expression was determined by RT-PCR technique. RESULTS: bFGF could augment CNP synthesis in human endothelial cells. Compared with control group,25 ng, 50 ng, 100 ng bFGF increased CNP contents in endothelial cells by 88% (P
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AIM: To observe the alteration of urotensin II (UII) receptors and contractile response to UII in rat aorta after balloon angioplasty injury. METHODS: The plasma membrane isolated from balloon injured aorta was used to study the binding of [ 125 I]-UII to the membrane and the contractile potency of UII on rat aorta was assayed. RESULTS: In contrast to the normal aorta, the contractile potency to UII enhanced in balloon injury artery and the calculated maximal number of specific binding sites (Bmax) was increased about 44% and 36% respectively in rat artery after balloon injury 3 and 21 days ( P
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AIM: To observe whether metallothionein plays a role in cardiac protective effect of basic fibroblast growth factor on anoxic/reperfusion (A/R) injury in cultured cardiomyocytes and study the possible mechanism of cardiac protection by bFGF.METHODS: The present study made the model of myocyte A/R injury after having a 24 h incubation by bFGF(10 -10、10 -9、10 -8 mol/L) and bFGF(10 -9 mol/L)+PD 098059 respectively. We measured the levels of MT and MDA in myocytes, and the changes of LDH and protein in cultured medium. We also counted the number of viable cell in groups.RESULTS: The contents of myocardial MT were significantly increased after treatment by bFGF. The levels of MT in 10 -10 mol/L、10 -9 mol/L and 10 -8 mol/L bFGF treated groups increased 54%\, 62%\, 76% respectively, compared with the A/R group, and the number of viable cell were also greatly increased, LDH and protein leakage in cultured medium and MDA contents in myocyte were dramatically decreased in bFGF treated groups. All the protection were completely disappeared with the inhibition of MT production with PD 098059, the inhibitor of mitogen-activated protein kinase(MAPK).CONCLUSION: MT involves in the protection of bFGF in cultured cardiomyocytes. It might be related with activation of MAPKase.
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AIM: To study the role and regulation of calcineurin(CaN) in angiotensin II(AngⅡ)-stimulated cardiacmyocyte hypertrophy of rats. METHODS: Using AngⅡ to induce the cultured cardiac myocyte hypertrophy of rats, and investigating the effect of CaN inhibitor on [ 3H]-leucine incorporation of AngⅡ-stimulated cardiomyocytes and the regulation of various factors on CaN activity in cardiomyocytes.RESULTS: AngⅡ can stimulate the CaN activity in cultured neonatal rat cardiomyocytes in a dose- and time-dependent manner. In cardiac myocytes incubated with 10, 100, 1000 nmol?L -1 of AngⅡ for 12h, the CaN activities increased respectively by 13%,57%( P
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] AIM: Lysophosphatidic acid (LPA) is a bioactive phospholipid known to have growth factor-like activity on fibroblasts, and is involved in cardiovascular diseases. Besides direct effects, usually, LPA can work together with other bioactive factors to regulate cardiovascular homeostasis by induction of their expression and production, or increase in their activity. Among variety of bioactive factors, adrenomedullin (ADM) is a multifunctional peptide with an important cytoprotective effect against cardiovascular damage, but the interaction between ADM and LPA on adventitia remains unknown. METHODS: The experiment was performed on the bath of isolated rat aortic adventitia, ADM produced and secreted from adventitia stimulated by LPA was detected by using radioimmunoassay, proliferation in adventitia cells was evaluated by the level of [3H]-thymine incorporation, and prepro ADM gene expression was measured by semi-quantitative reverse transcriptase polymerase chain reaction. RESULTS: It was found that LPA stimulated aortic adventitia to secrete ADM and express its mRNA in a concentration-dependent manner. ADM inhibited LPA-induced proliferation in adventitial cells, and attenuated the activity of mitogen activated protein kinase (MAPK) stimulated by LPA. In contrast, the treatment with specific antagonists of ADM receptor potentiated the LPA-induced proliferation in adventitial cells. CONCLUSION: LPA stimulates adventitia to produce and secrete ADM, and in turn, ADM produced by adventitia regulates the vascular biological effects of LPA. [
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AIM: The activity and expression of neutral endopeptidase (NEP) and the adrenomedullin (ADM) contents in various tissues were observed in septic shock and control rats to study the possible role of NEP in the change of ADM contents in tissues during septic shock. METHODS: The septic shock model of rats were established by cecal ligation and puncture (CLP). ADM contents, NEP activities, level of NEP mRNA and NEP protein were measured. RESULTS: (1) In early septic shock (ES), the ADM contents were generally higher in detected tissues, the NEP activity in left ventricle and small intestine were lower and was higher in blood than those in controls, and in lung, kidney and aorta were similar with the controls. NEP immunoreactive staining were less in lung, left ventricle, endothelium and media of aorta, but more in adventitia of aorta and kidney than those of the controls; (2) In late septic shock (LS), the ADM contents in small intestine was less but in plasma and other tissues were higher, and the NEP activity were less in plasma and other tissues than those in ES. The NEP immunoreactive staining were less in heart, endothelium and media of aorta, lung and kidney than those in ES, and was no significant change in adventitia of aorta compared with those of ES. RT-PCR found that NEP gene expression were significantly less in left ventricle, aortas, lung and small intestine than those in the controls. CONCLUSIONS: In septic shock rats, the NEP activity changes heterogeneously but the ADM contents elevate in most tissues. These results indicate that during the septic shock, the local concentrations and actions of ADM in various tissues may be regulated differently by the NEP. [
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AIM: To observe whether metallothionein plays a role in cardiac protective effect of basic fibroblast growth factor on anoxic/reperfusion (A/R) injury in cultured cardiomyocytes and study the possible mechanism of cardiac protection by bFGF.METHODS: The present study made the model of myocyte A/R injury after having a 24 h incubation by bFGF( 10-10、10-9、10-s mol/L) and bFGF( 10-9 mol/L) + PD098059 respectively. We measured the levels of MT and MDA in myocytes, and the changes of LDH and protein in cultured medium. We also counted the number of viable cell in groups. RESULTS: The contents of myocardial MT were significantly increased after treatment by bFGF. The levels of MT in I0-l0 mol/L、10-9 mol/L and 10-8 mol/L bFGF treated groups increased 54 %、 62%、 76% respectively, compared with the A/R group, and the number of viable cell were also greatly increased, LDH and protein leakage in cultured medium and MDA contents in myocyte were dramatically decreased in bFGF treated groups. All the protection were completely disappeared with the inhibition of MT production with PD098059, theinhibitor of mitogen- activated protein kinase(MAPK). CONCLUSION: MT involves in the protection of bFGF in cultured cardiomyocytes. It might be related with activation of MAPKase.
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AIM: To study lipopolysaccharide (LPS)-stimulated secretion of endothelin-1 (ET-1) and adrenomedullin (Adm) from human vascular endothelial cells (HVEC) and its mechanism. METHODS: In cultured HVEC, LPS was used to stimulate ET-1 and Adm secretion from HVEC. The contents of ET-1 and Adm in medium were determined by radioimmunoassay. RESULTS: LPS stimulated secretion of ET-1 and Adm from HVEC in time-dependent and concentration-dependent manner. The ratio of secreted ET-1 to Adm was not changed compared with the control group. The increase of ET-1 could be inhibited by inhibitor of extracellular signal-regulated protein kinases (PD 098059 ) and inhibitor of P38 kinase (SB 202190 )( P 0.05).CONCLUSION: ERKs and P38 signal pathways may play an important role in the secretion of ET-1 from LPS -stimulated HVEC, while only P38 kinase signal pathway is invovled in the secretion of Adm.
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AIM: To observe the effects of aortal angiotensin Ⅱ (Ang Ⅱ )levels and AngⅡ receptor in the hy- pertensive rat models. METHODS: Intraperinoneal injection of L - Nw - nitro-arginine (L - NNA) into rats induced hypertensive model, the binding of aortal Ang Ⅱ receptor and the contents of aortal tissue Aug Ⅱ and plasma NO2-+ NO3- (NOx) were determined. RESULTS: Compared with the control group, the bind pressure of the rats treated with L - NNA was significantly increased by 142% (P
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AIM: To investigate the effect of chronic hypoxia-hypercapnia and L-arginine (L-Arg) liposome on L-Arg transport in rats pulmonary artery. METHODS: Forty Sprague-Dawley rats were randomly divided into four groups, normal control group (NC), chronic hypoxia-hypercapnia group (HH), chronic hypoxia- hypercapnia group+L-Arg (HL) and chronic hypoxia-hypercapnia group+L-Arg liposome (HP). Changes in pulmonary artery L-Arg transport and pulmonary arterial microscopy were observed. RESULTS: (1) The mean pulmonary artery pressure (mPAP) and weight ratio of right ventricle to left ventricle and septum (RV/LV+S) in HH group were higher than those in NC group, and in HP group was lower than that in HH group and HL group, but there was no significant difference between HL group and HH group; (2) At 0.005 mmol/L, 0.01mmol/L, 0.02mmol/L, 0.05 mmol/L, 0.1 mmol/L and 0.2mmol/L concentration of L-Arg, the velocity of L-Arg transport in HH group was lower than that in NC group, and in HL group higher than in HH group, and in HP group was much higher than that in HH group and in HL group. (3) Light microscopy showed that vessel well area/total area (WA/TA) and media thickness of pulmonary arterioles (PAMT) were much higher in rats of HH group than those in NC group, WA/TA and PAMT in HP group were obviously improved. CONCLUSION: The above results indicated that there existed a functional disturbance in L-Arg transport of pulmonary artery in rats chronically exposed to hypoxia-hypercapnia, and it was obviously enhanced when liposome was used as L-Arg carrier. Thus, it appears that liposome-L-Arg may have clinical perspective in the treatment of chronic hypoxic pulmonary hypertension.
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AIM: Metallothioneins (MTs) are cysteine-rich metal-binding proteins that exert cytoprotection during metal exposure and oxidative stress. The present study was designed to investigate whether MT can directly protect NTPase on nuclear envelope from damage induced by hydroxyl radical.METHODS: Isolated hepatic nuclei from rat liver were exposed to Fe 2+ /H 2O 2 with or without MT, and the NTPase activity on nuclei was assayed using ATP and GTP as substrate, respectively. RESULTS: Incubation of rat hepatic nuclei with the Fe 2+ /H 2O 2 (in ?mol?L -1 / ?mol?L -1 : 0 1/0 5, 0 5/2 5, 1/5, 5/25) resulted in a concentration-dependent decrease in nuclear NTPase activities ( P0 05 ). In addition, incubation of hepatic nuclei with only MT had no effect on nuclear NTPase activity. CONCLUSION: These data demonstrate that hydroxyl radical generated from Fe 2+ /H 2O 2 might attack nuclear NTPase. MT antagonistically reduces toxicity of Fe 2+ /H 2O 2 system to the NTPase.
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AIM To investigate effect of urotensin Ⅱ (U Ⅱ )on proliferation of aorta smooth muscle cells (ASMC) of rat and study the signal transduction pathway of it. MEfHODS in cultured ASMC of rat, U Ⅱ was used to stimulate proliferation of these cells and levels of [3H]-TdR incorporation were used to evaluate the sped of DNA synthesis, and different inhibitors were ed to study the action of different signal transduction pathway of mitogenic effect of UⅡ on VSMC. RESULTS. 1 ? 10-9~l ? 10-7 mol. L-l U Ⅱ caused marked concentration-de pendent increasing of [3H]-TdR incorporation of ASMC [3H]-TdR incorporation of 1 ? 10-9, 1 ? 10-8 and １ ? 10-7 mol. L－l U Ⅱ were 22%'(P
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AIM: To observe the effect of adrenomedullin(ADM)on proliferation of vascular smooth muscle cells(VSMC) induced by urotensin Ⅱ(UⅡ). METHODS: DNA synthesis of cultured rat aortic VSMC was measured by -TdR incorporation. The activities of mitogen activated protein kinase(MAPK) were determined by isotope tagged with [?- 32 P]-ATP. RESULTS: UⅡ(10 -8 mol/L) significantly increased -TdR incorporation of VSMC and MAPK activities by 38%( P0.05 ), 32%( P0.05 ), 32%( P