Negative Chronotropic Action of Ketanserin on Isolated Rat Right Atria and Its Mechanism Analysis
- VernacularTitle:Ketanserin对大鼠离体右心房的负性频率作用及机理分析
- Author:
Chaoyu MIAO
- Publication Type:Journal Article
- Keywords:
Ketanserin;
isoproterenol;
5-bydroxytryptamine;
atropine;
dose-response curve;
isolated atrium;
heart rate
- From:
Academic Journal of Second Military Medical University
1985;0(05):-
- CountryChina
- Language:Chinese
-
Abstract:
The direct effect of Ketanserin (Ket) on heart rate and its mechanism were studied using isolated male Sprague-Dawley rat right atria. Ket (0.1-300?mol/L) produced apparent negative chronotropic action in a dose-dependent manner, the pD2 value was 4.8. Atropine (30 nmol/L) did not affect the negative chronotropic action of Ket Differing from the ?-receptor blocking agent propfanoloi (1?mol/L), Ket (1.5?mol/L) did not change the positive chronotropic dose-response curve for isoprenaline, but shifted the positive chronotropic dose-response curve for 5-hydroxytryptamine to the right and depressed its maximal response. These results indicate that the negative chronotropic action of Ket was related to the blockade of the 5-HT2-serotonergic receptor in the sinus node of rat atria, whereas the ?-adrenoreceptor and M-cholinergic receptor were not involved in the negative chronotropic action of Ket
