Human Reproduction vol.5 no.4 pp.387-390, 1990 Bradykinin induces contractions of the human ovarian follicular wall in vitro

Bradykinin has been shown to have a positive modulatory role in the ovulatory process. In the present study, the contractile properties elicited by bradykinin (10~12-10~5 M) in the isolated human follicular wall were examined. Strips from the follicular base and apex were mounted separately and supervised at 37°C with oxygenated HEPES buffer in tissue chambers. The contractile activity was recorded isometrically by a force transducer (Grass model FT03), under a passive tension of 5 mN. Preovulatory follicles (cycle day 10-14) were more sensitive to bradykinin than follicles of an earlier developmental stage (cycle day 1-9). The response to bradykinin was not altered by the addition of indomethacin (10~7 M), atropine (10~6 M) or phenoxy-henzamine (10 7 M). These data suggest that the contraction caused by bradykinin is a specific effect, which, under physiological conditions, might contribute to the ovulatory process by inducing a rise in tone in the follicle thereby facilitating the extrusion of the oocyte through the digested follicular apex. Key words: bradykinin/kinin/contractility/human/ovulation/ follicl