title: The sympathomimetic activity of fenfluramine hydrochloride on rat vas deferens.
abstract: 1. The peripheral, pharmacological effects of the anorexigenic agent, fenfluramine hydrochloride, have been investigated on rat isolated vas deferens. 2. Characteristic spiked contractions were observed within 2 to 3 min after exposure to fenfluramine; these contractions reached a rate of around 13 per min and were of variable height. 3. Pre-treatment of vasa with the indirectly acting sympathomimetic amine, tyramine, greatly reduced both the height and rate of contraction induced by fenfluramine. 4. The uptake inhibitor, desipramine, required a concentration in excess of 10 micronM to affect fenfluramine-induced contractions. Effects of desipramine on fenfluramine contractions were of equal magnitude whether desipramine was administered before fenfluramine or at the height of the fenfluramine-induced contractions. 5. Pre-treatment with debrisoquine (0.5 mM), reduced the contractions in response to fenfluramine over a period of time. 6. Fenfluramine, added to vasa from rats which had been injected intraperitoneally with 5 mg/kg reserpine 24 h and 48 h previously, failed to induce its characteristic contractions. 7. It is concluded that fenfluramine can be classed as an indirectly acting sympathomimetic amine on peripheral adrenergic nerve terminals.
mesh_terms: D000818:Animals; D003647:Debrisoquin / Q000494:pharmacology; D003891:Desipramine / Q000494:pharmacology; D004347:Drug Interactions; D005277:Fenfluramine / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D009411:Nerve Endings / Q000187:drug effects; D051381:Rats; D012110:Reserpine / Q000494:pharmacology; D013566:Sympathomimetics; D013997:Time Factors; D014439:Tyramine / Q000494:pharmacology; D014649:Vas Deferens / Q000187:drug effects
chemical_list: D013566:Sympathomimetics; D005277:Fenfluramine; D012110:Reserpine; D003891:Desipramine; D003647:Debrisoquin; D014439:Tyramine