血管紧张素(1-7)和依那普利拉对烧伤血清离体灌注大鼠心脏功能的影响

目的 了解血管紧张素(1-7)Ang(1-7)]和依那普利托对烧伤血清离体灌注大鼠心脏功能的影响.方法 选取80只SD大鼠制备烧伤血清.另取24只SD大鼠心脏建立Langendofff离体灌注模型.根据灌注液不同,将大鼠心脏分为K-H液组、含体积分数20%烧伤血清的K-H液组(烧伤血清组)、含体积分数20%烧伤血清和2μg/mL依那普利拉的K-H液组(依那普利托组)、含体积分数20%烧伤血清和1 nmoL/mL Ang(1-7)的K-H液组Ang(1-7)组].各组大鼠心脏连续灌注30min上述溶液后,检测其左心室收缩压(LVSP)、左心室舒张末期压(LVEDP)、左心室压力最大上升/下降速率(±dp/dt max),以及冠状动脉血流量(CF)和冠状动脉流出液中肌酸激酶(CK)、乳酸脱氢酶(LDH)的含量.结果 与K-H液组LVSP(11.2±1.0)kPa,1 kPa=7.5 mm Hg]、+dp/dt max(642±53)kPa/s]、-dp/dt max(380±61)kPa/s]及CF值比较,烧伤血清组、依那普利拉组和Ang(1.7)组LVSP(5.9±0.8)、(8.0±1.1)、(8.9±1.3)kPa]、+dp/dt max(275±37)、(454±48)、(479±63)kPa/s]、-dp/dt max(135±35)、(219±47)、(277±58)kPa/s]及CF值均明显降低(P<0.05或P<0.01),LVEDP和冠状动脉流出液中CK、LDH的含量升高.与烧伤血清组比较,依那普利拉组和Ang(1-7)组CF、LVSP及±dp/dt max均明显升高(P<0.05或P<0.01),LVEDP和冠状动脉流出液中CK、LDH的含量明显降低(P<0.01).结论 Ang(1-7)和依那普利拉均能有效改善烧伤血清离体灌注大鼠左心功能,减轻心肌损伤.

Effects of angiotensin (1-7) and enalaprilat on function of isolated rat heart perfused by burn serum

Objective To investigate effects of angiotcnsin ( 1-7 ) Ang( 1-7 ) ] and enalaprilat on function of isolated rat heart perfused by burn serum. Methods Eighty SD rats were used to prepare burn serum. Hearts of another 24 SD rats were isolated to reproduce Langendorff perfusion model. The rat hearts were divided into different groups with different perfusion fluids as K-H buffer group, K-H buffer containing 20% burn serum group ( burn serum group) , K-H buffer containing 20% burn serum and 2 μg/mL enala-prilat group (enalaprilat group), and K-H buffer containing 20% burn serum and 1 nmol/mL Ang(1-7) group Ang(1-7) group]. The rat hearts were perfused for 30 mins with each of above-mentioned fluids in different groups. Then left ventrieular systolic pressure (LVSP) , left ventricular end diastolic pressure ( LV-EDP) , ± dp/dt max, coronary flow(CF) , level of creatine kinase (CK) and lactate dehydrogenase (LDH) in respective coronary effluent were determined. Results Compared with LVSP ( 11.2 ± 1.0 kPa, 1 kPa = 7.5 mm Hg), +dp/dt max (642±53 kPa/s), -dp/dt max (380±61 kPa/s) and CF level in K-H buffer group, CF, LVSP(5.9±0.8, 8.0±1.1, 8.9±1.3 kPa, respectively), +dp/dt max(275±37, 454±48, 479±63 kPa/s, respectively), - dp/dt max ( 135±35, 219±47, 277±58 kPa/s, respectively ) of burn serum group, those levels in Ang(1-7) group, and enalaprilat group were decreased obviously(P<0.05 or P <0.01 ), but LVEDP, level of CK and LDH in coronary effluent were increased. Compared with those parameters in burn serum group, CF, LVSP, ±dp/dt max of Ang(1-7) group and enalaprilat group were increased obviously(P<0.05 or P<0.01), and LVEDP, level of CK and LDH in coronary effluent were decreased obviously(P<0.01). Conclusions Ang(1-7) and enalaprilat can effectively improve left ventricular function of isolated rat heart perfused by burn serum and mitigate myocardial injury.