Effects of fluoxetine hydrochloride and fluvoxamine maleate on different preparations of isolated guinea pig and rat organ tissues.

1. Fluoxetine and fluvoxamine reinforced the response to norepinephrine of isolated rat vas deferens incubated in Krebs-Henseleit solution. 2. This reinforcement disappeared when cocaine, 17 beta-estradiol, and propranolol were added to the incubation medium. 3. Fluoxetine and fluvoxamine did not have antimuscarinic effect, but they did have antihistaminic effect, and at high concentrations they inhibited the contraction induced by potassium ion on the isolated rat uterus preparation (IC50 3.99 x 10(-6) and 1.82 x 10(-5) M, respectively).