[Effects of angiotensin (1-7) and enalaprilat on function of isolated rat heart perfused by burn serum].
OBJECTIVE
To investigate effects of angiotensin (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 microg/mL enalaprilat 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 ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), +/- 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.
Institute of Burn Research, Southwest Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, the Third Military Medical University, Chongqing 400038, China.
Ze-Yuan
ZY
Lei
Yue-Sheng
YS
Huang
Rong
R
Xiao
Bing-Qian
BQ
Zhang
Qiong
Q
Zhang
D000803:Angiotensin I / Q000494:pharmacology*; D000818:Animals; D002056:Burns / Q000097:blood; D015773:Enalaprilat / Q000494:pharmacology*; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D044967:Serum; D016277:Ventricular Function, Left / Q000187:drug effects*
D010446:Peptide Fragments; D000803:Angiotensin I; D015773:Enalaprilat; C118790:angiotensin I (1-7)