Radioimmunoassays were used to measure the concentration changes of plasma endothelin(ET) and atrial natriuretic peptide(ANP) during the onset and after termination of paroxysmal supraventricular tachycardia(SVT). 30 ...Radioimmunoassays were used to measure the concentration changes of plasma endothelin(ET) and atrial natriuretic peptide(ANP) during the onset and after termination of paroxysmal supraventricular tachycardia(SVT). 30 cases were reviewed and compansons with 42 normal subjects were made. There are very significant differences(P<0.0001) in the concentration changes of both plasma ET and ANP during the onset and 30 minutes after the termination of SVT. During the onset period of SVT. the plasma ET and ANP were markedly elevated and 30 minutes after its termination they were lowered significantly, but their concentrations were still 2-fold higher than ihose of the control group. As the biological effects of ANP and ET are antagonistic to each other. their parallel elevation and lowering of plasma concentrations during and.after the termination of SVT reveal that these 2 hormones parucipate in the pathophysiological process of SVT. This phenomenon is possibly one of the homeostatic regulatory functions in the organism.展开更多
OBJECTIVE: To investigate the effects of the mixed endothelin receptor antagonist, bosentan, combined with the long-acting calcium channel blocker, amlodipine, compared to the angiotensin-converting enzyme inhibitor, ...OBJECTIVE: To investigate the effects of the mixed endothelin receptor antagonist, bosentan, combined with the long-acting calcium channel blocker, amlodipine, compared to the angiotensin-converting enzyme inhibitor, cilazapril, on the progressive renal injury in spontaneous hypertensive rats (SHR) with diabetes. METHODS: Diabetic hypertensive rats (SHR-DM) were induced by streptozotozin injected in male SHR (7-week-old),and divided into an untreated and three treated groups: 1) cilazapril treated group; 2) bosentan+amlodipine treated group; and 3) amlodipine treated group. Wistar Kyoto rats (WKY) and SHR rats served as normotensive and hypertensive control, respectively. The mean arterial blood pressure, renal function, endothelin and angiotensin II levels as well as the protein expression of renal extracellular matrix components and transforming growth factor (TGF)-beta1 were determined at the end of the 4th week. RESULTS: Mean arterial blood pressure significantly increased in SHR and SHR-DM rats compared to WKY rats. All the therapies reduced the blood pressure to normal levels. However, the enhanced urinary protein excretion, the decreased creatinine clearance as well as the increased plasma and intrarenal endothelin and angiotens in II levels were found in the untreated SHR-DM and prevented by treatment with bosentan+amlodipine and cilazapril. Similarly, these two kinds of therapies in SHR-DM abolished the overexpression of renal TGF-beta1 by Western blot analysis and reduced the accumulation of collagen type IV, laminin and fibronectin proteins by an immunochemical approach. Amlodipine monotherapy had no detectable effects on the above parameters. CONCLUSION: Bosentan combined with amlodipine can offer similar renoprotective effects on that of cilazapril and may be a potent therapy to attenuate renal injury by reducing renal protein levels of TGF-beta1 in diabetes with a hypertensive state.展开更多
文摘Radioimmunoassays were used to measure the concentration changes of plasma endothelin(ET) and atrial natriuretic peptide(ANP) during the onset and after termination of paroxysmal supraventricular tachycardia(SVT). 30 cases were reviewed and compansons with 42 normal subjects were made. There are very significant differences(P<0.0001) in the concentration changes of both plasma ET and ANP during the onset and 30 minutes after the termination of SVT. During the onset period of SVT. the plasma ET and ANP were markedly elevated and 30 minutes after its termination they were lowered significantly, but their concentrations were still 2-fold higher than ihose of the control group. As the biological effects of ANP and ET are antagonistic to each other. their parallel elevation and lowering of plasma concentrations during and.after the termination of SVT reveal that these 2 hormones parucipate in the pathophysiological process of SVT. This phenomenon is possibly one of the homeostatic regulatory functions in the organism.
基金ThisresearchworkwassupportedbyMinistryofPublicHealthandShanghaiBairenProjectFoundation (No .98BR0 3 8)
文摘OBJECTIVE: To investigate the effects of the mixed endothelin receptor antagonist, bosentan, combined with the long-acting calcium channel blocker, amlodipine, compared to the angiotensin-converting enzyme inhibitor, cilazapril, on the progressive renal injury in spontaneous hypertensive rats (SHR) with diabetes. METHODS: Diabetic hypertensive rats (SHR-DM) were induced by streptozotozin injected in male SHR (7-week-old),and divided into an untreated and three treated groups: 1) cilazapril treated group; 2) bosentan+amlodipine treated group; and 3) amlodipine treated group. Wistar Kyoto rats (WKY) and SHR rats served as normotensive and hypertensive control, respectively. The mean arterial blood pressure, renal function, endothelin and angiotensin II levels as well as the protein expression of renal extracellular matrix components and transforming growth factor (TGF)-beta1 were determined at the end of the 4th week. RESULTS: Mean arterial blood pressure significantly increased in SHR and SHR-DM rats compared to WKY rats. All the therapies reduced the blood pressure to normal levels. However, the enhanced urinary protein excretion, the decreased creatinine clearance as well as the increased plasma and intrarenal endothelin and angiotens in II levels were found in the untreated SHR-DM and prevented by treatment with bosentan+amlodipine and cilazapril. Similarly, these two kinds of therapies in SHR-DM abolished the overexpression of renal TGF-beta1 by Western blot analysis and reduced the accumulation of collagen type IV, laminin and fibronectin proteins by an immunochemical approach. Amlodipine monotherapy had no detectable effects on the above parameters. CONCLUSION: Bosentan combined with amlodipine can offer similar renoprotective effects on that of cilazapril and may be a potent therapy to attenuate renal injury by reducing renal protein levels of TGF-beta1 in diabetes with a hypertensive state.
