马氏钳蝎蝎毒对大鼠左心室功能的影响

The effects of scorpion venom (Buthus martensi Ka-rsch)on rat left ventricle function

经大鼠右颈总动脉左心室插管,静脉注射马氏钳蝎蝎毒,观察血压、心率、左心室内压、左心室舒张末期压、左心室内压最大变化速率、零负荷时左室心肌最大收缩速度等指标的变化。结果表明,马氏钳蝎蝎毒具有升高血压、增强心肌收缩力、显著改善左心室收缩功能的作用。其升压作用与肾上腺素α受体有关,其正性肌力作用与肾上腺素β受体关系不大,蝎毒分子内的4对双硫键是其产生心血管作用所必需的。

In order to investigate the cardiovascular effects of the Scorpion venom ( Bu-thus martensi Karsch),the left ventricle of rats was catheterized via the right carotid artery. The LVP, LVEDP, + dp/dtmax, Vmax, HR and BP were observed. The results are as follows Intravenous injection of the venom ( 60μg/kg ) , in comparison with the control, elicited an obvious hypertension and increase of cardiac contractility, both of which lasted for one hour, while the heart rate did not change significantly. Pretreating the rats with alpha-adrenergic blocker phentola-mine antagonized the hypertensive effects, but not the increase of cardiac contractility. However,pretreatment with beta-adrenergic blocker propranolol has no influence on the effects of the venom. It suggests that the hypertensive effects aredue to the activation of alpha-adrenergic receptor, whereas the increase of cardiac contractility maybe did not result from the activation of betaadrenergic receptor. The venom,treated with dithiothreitol before injection,had on cardiovascular effects, indicating that the intact disulfide bridges are necessary for the cardiovascular effects of the venom.