Abstract:Aim To compare the dynamic changes of neuroendocrine hormone levels on different treatment groups,in order to understand the angiotensin converting enzyme inhibitor and β-receptor blockers effect on neuroendocrine hormone after valve replacement. Methods 60 patients were randomly divided into A,B,C groups,and were given different drugs after treatment.We took blood samples in the preoperative and different time of postoperation to determine plasma level of angiotensinⅡ,atrial natriuretic polypeptide,aldosterone. Results After valve replacement surgery,plasma angiotensinⅡ,atrial natriuretic polypeptide,aldosterone concentrations at all time measured compared with the preoperative levels had no significant differences in A group.But in B group and C group,compared with the preoperative and postoperative 1 week the plasma atrial natriuretic polypeptide concentrations had no significant change,plasma atrial natriuretic polypeptide concentrations measured in postoperative 2 weeks started to decline,plasma aldosterone concentrations started to decline until 4 weeks after operation;until postoperative 16 weeks the plasma angiotensinⅡ concentrations in B group had a significant decrease;and in C group the plasma angiotensinⅡ concentrations had significant decrease in 8 weeks after operation.Compared with B group and C group,the decreased level of plasma angiotensinⅡ,aldosterone concentrations after operation had no significant difference,but the decreased level of plasma atrial natriuretic polypeptide concentrations in C group was better than B group. Conclusion Patients after mechanical heart valve replacement surgery with routine cardiocinetic,diuretic therapy,and in addition supplemented angiotensin converting enzyme inhibitor and/or β-blocker treatment can effectively reduce the neuroendocrine hormone levels.

Abstract:Aim Effects of captopril on angiotensin Ⅱ type 1 receptors (AT1R) and angiotensin Ⅱ type 2 receptors (AT2R) were studied in excess load-pressured hypertrophied cardiac muscles of adult rats. Methods The experiment adopts the method of narrowing and contraction the aorta in adult and health rats,hence establishing the model of animals with hypertensions and cardiac hypertrophies. By comprehensive applications of cardiac-tube, immunity tissue chemistry, and the techniques of image disjunction, to observing changes of AT1R and AT2R on hypertrophied cardiac muscles of AC rats in rats are discussed. Results (1) Load-pressured of left-ventricular and hypertrophy aggravates increase remarkably as the pressure loading time lasts. When it comes to 6 weeks after AC, Vwt reaches (1310±55), in group SO6W it is (209±8.8, p<0.01). When captopril is used till 6 week after AC, the hypertrophy in cardiac tissue decrease to the control group. (2)AngⅡ in cardiac tissue of adult rats grows to as high as (1219.5± 30.13 g/ml), which is nearly twice as high as that of control group (613.0±132.3). After using cap, left-ventricular hypertrophied decreases more significantly than control group. (3)expression of AT1Receptors increase remarkably as the pressure loading time lasts. Expression of AT1 in LV in rats (IOD value) reaches (124±32)

Abstract:Aim To evaluate the effectiveness of nifedipine and enalaprilat on collagen proliferation after balloon injury in a rabbit model. Methods Thirty-two healthy male New Zealand white rabbits were divided into control group, nifedipine group and enalaprilat group. Conventional balloon angioplasty in the right common iliac artery was done. Arterial bloods were taken before angioplasty, 30 minuets and 2 weeks after angioplasty for analyzing plasma AngⅡ. For histology, Massons staining was performed two weeks later. All the specimens were analyzed using a computerized imaging analysis system. Results In the control group, plasma AngⅡ elevated from 2.70±0.31 g/L to 2.83±0.18 g/L 30 min after angioplasty (P<0.05), and returned to 2.50±0.26 g/L two weeks later (P<0.05). There was no significant AngⅡdifferences between the control and the nifedipine groups. Enalaprilat significantly inhibited plasma AngⅡ elevation 30 min after angioplasty. Histological computerized imaging analysis showed significant collagen proliferation after angioplasty (P<0.01). There was a significant decrease of collagen proliferation in the enalaprilat group (P<0.01). Conclusions Significant vascular wall collagen proliferation was observed after angioplasty. Enalaprilat inhibited vascular wall collagen proliferation, thus may be effective in the prevention of resrenosis after successful pecutaneous transluminal coronary angioplasty.

Abstract:Aim To investigate enalapril, nifedipine and lovastatin had the effects on experimental atherosclerosis in cholesterol rabbits. Methods Thirty seven rabbits were divide into five groups accidentally. Group A received normal chow, group B received cholesterol, group C received cholesterol plus enalapril, group D received cholesterol plus nifedipine and group E received cholesterol plus lovastatin. All rabbits were fed for sixteen weeks. At the end of the study, all animals were killed to determine the aortas cholesterol concentration and the percentage of aortic lesions covering the intimal surface. Results Enalapril and nifedipine didn’t affect lipid level. Lovastatin reduced total cholesterol, triglyceride, and LDL level. The LDL/HDL ratio was less in lovastatin group than that in cholesterol, enalapril, and nifedipinegroups. The aortas cholesterol concentration and the plaque square in all drug groups were lower than in cholesterolgroup (P<0.05). Conclusion These three drugs had the effects of prophylaxis in experimental atherosclerosis.