Microvasculature of preovulatory follicles: comparison of in situ and in vitro perfused rabbit ovaries following stimulation of ovulation.
Perifollicular vasculature undergoes significant morphologic changes as ovulation approaches. These vascular changes were observed in in vitro perfused and in situ rabbit ovaries by means of scanning electron microscopy of microcorrosion casts. Casts were made in in situ unstimulated ovaries, in situ ovaries stimulated with human chorionic gonadotropin, in vitro perfused unstimulated ovaries, and in vitro perfused ovaries after an ovulation-inducing dose of human chorionic gonadotropin, prostaglandin F2 alpha, histamine, or norepinephrine. Dilated vessels, extravasation of resin from weakened vessels, and filling defects at the apex of the follicle were observed in in situ ovaries 9 to 12 hours after stimulation and in in vitro perfused ovaries 4 to 6 hours after human chorionic gonadotropin. In vitro perfused ovaries stimulated with prostaglandin F2 alpha or histamine demonstrated dilated capillaries with extravasation of the resin and filling defects at the apex of large follicles. Norepinephrine-stimulated ovaries showed incomplete filling of vessels, although some large follicles showed extravasation of resin. The occurrence of dilated vessels, extravasation of resin, and filling defects is indicative of preovulatory vascular changes in both in situ and in vitro perfused ovaries, regardless of the ovulatory stimulus.
D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D015237:Dinoprost; D005260:Female; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D008833:Microcirculation; D008855:Microscopy, Electron, Scanning; D009638:Norepinephrine / Q000494:pharmacology; D006080:Ovarian Follicle / Q000098:blood supply; D010053:Ovary / Q000098:blood supply* / Q000187:drug effects; D010060:Ovulation / Q000187:drug effects; D010062:Ovulation Induction; D010477:Perfusion; D011460:Prostaglandins F / Q000494:pharmacology; D011817:Rabbits; D013268:Stimulation, Chemical
D006063:Chorionic Gonadotropin; D011460:Prostaglandins F; D006632:Histamine; D015237:Dinoprost; D009638:Norepinephrine