ABSTRACT
ObjectiveTo observe the effect ofShenmai injection on isolated cardiac systolic and diastolic function in myocardial infarction rats.Methods32 rats were randomly divided into a control group, a propranolol group, aShenmai + propranolol group and aShenmai group. The myocardial infarction models were made by ligating the left anterior descending coronary artery of rats .The heart was taken from myocardial infarction rat after 3 days. The indexes of Isometric tension (IT), Diastolic tension (DT), heart rate (HR), the maximum pressure ascending and descending rate of left ventricle (± LVdp/dtmax) (mmHg/s) were recorded by using Langendorff isolated heart perfusion technique at 5min before and 0.5 h, 1 h, 2 h after perfusion.ResultsCompared with the control group, the IT (2.01 ± 0.02 g, 1.52 ± 0.01 g, 1.53 ± 0.02 g), the HR (326 ± 32 time/min, 331 ± 41 time/min, 307 ± 37 time/min) and the ±LVdp/dtmax (4 012 ± 193 mmHg/s, 3 729 ± 174 mmHg/s, 3 631 ± 123 mmHg/s; 3 565 ± 202 mmHg/s, 3 632 ± 154 mmHg/s, 3 601 ± 129 mmHg/s) were apparently decreased in the propranolol group at 0.5 h, 1 h, 2 h after perfusion, and the differences were statistically significant (P 0.05).ConclusionsShenmaiinjection can improve myocardial contractility in isolated heart of myocardial infarction rats, however, propranolol can completely block the strong heart effect ofShenmaiinjection. This suggests thatShenmai injection has a beta receptor agonist effect.