Abstract
Fluvoxamine (FLV), a selective serotonin reuptake inhibitor (SSRI) antidepressant, caused a dose-dependent decrease in rate and contractile force of the isolated guinea-pig atria. These effects significantly blocked by DPCPX, a specific A1 receptor antagonist. Theophylline, an A1/A2A receptor antagonist, also prevented the inotropic and chronotropic effect of FLV. The atrium was dissected out and suspended in modified Krebs solution under physiologic conditions. Drug was added to the solution. The changes in rate and contractions were measured using a physiograph. The data indicate that DPCPX and theophylline prevent the inotropic and chronotropic effects of FLV on atria, but these effects were not prevented by atropine and DMPX, an A2 receptor antagonist. Adenosine A1 receptor blockade attenuates FLV effects in isolated guinea-pig atria.