[Effect of xin an granule on electrophysiological response of ventricular muscle cell in rabbits with ischemia].
OBJECTIVE
To investigate the electrophysiological effect of Xin' an granule (XAG) on ventricular muscle cell in ischemic rabbits.


METHODS
A total of 48 rabbits were divided into the normal group and the ischemic group, and then subdivided into three groups, the control group, the high and low-dose XAG groups, 8 in each group. Rabbits in the low-dose XAG group and the high-dose XAG group were gastrogavaged XAG at the daily dose of 0. 85 g/kg and 3.40 g/kg, while the others in the control group were given the equal dosage of normal saline. All the rabbits were treated three times per day for successive 10 days. The rabbit model of ischemia was established by intravenous injected with 2. 5 U/kg posterior pituitary injection. Five minutes later, the monophasic action potential (MAP) and electrocardiogram (ECG) of each rabbit in the different groups were recorded and compared.


RESULTS
(1) To normal rabbits, XAG could significantly shorten the action 50% and 90% potential duration (APD)50 and APD90 of ventricular muscle cell (P < 0.05 ), and high-dose of XAG could significantly increased the Vmax of MAP(P <0. 05). (2) While to ischemic rabbits, XAG could significantly prolong APD50 and APD90, and significantly increased the action potential amplitude (APA) and Vmax of MAP (P < 0. 05).


CONCLUSIONS
(1) XAG can significantly shorten APD50 and APD90 of ventricular muscle cell, and high-dose XAG significantly increase the Vmax of MAP of normal rabbits. (2) XAG can delay and alleviate the manifestation characteristics of action potential of ventricular muscle cell during ischemia.
Yang
Si-jin
SJ
Luzhou Medical College, Sichuan. ysjimn@sina.com
Chen
Mei-juan
MJ
Yang
Hai-tao
HT
D000200:Action Potentials / Q000187:drug effects*; D000818:Animals; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography; D006352:Heart Ventricles / Q000166:cytology / Q000187:drug effects*; D008516:Medicine, Chinese Traditional; D017202:Myocardial Ischemia / Q000503:physiopathology*; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000502:physiology; D011817:Rabbits