Evidence for Preferential Transfer of Prostaglandin F2α to the Ovarian Artery Following Intrauterine Administration in Cattle1

Publisher Website
Google Scholar
Abstract
The necessity of RNA synthesis within the ovarian follicle cells for gonadotropin-induced oocyte maturation was examined using isolated ovarian tissues of Xenopus laevis. Studies using [5-3H]uridine revealed that the radioactivity incorporated into the RNA of the theca epithelium was much higher than that incorporated into the RNA of the follicle cells and oocyte. No difference was observed in the quantity of radioactivity that was incorporated into the RNA of hormone-treated ovarian tissues as compared to that for untreated tissues. However, inhibitor studies indicated that actinomycin D and α-amanitin had a variable inhibitory effect on gonadotropin-induced maturation when they were applied to the ovarian follicles prior to the gonadotropin. On the contrary, no significant inhibitory effect on maturation was observed if these inhibitors were applied either simultaneously with or after the initiation of gonadotropin treatment, even though bulk RNA synthesis was always inhibited by approximately 85% with actinomycin D. Ethidium bromide, on the other hand, was always effective in inhibiting gonadotropin-induced maturation, although there was no detectable suppression in the incorporation of [3H]uridine into bulk RNA. All three drugs had no inhibitory effect on progesterone-induced maturation. A working hypothesis has been proposed that can account for the variable inhibitory effect of actinomycin D and α-amanitin on gonadotropin-induced oocyte maturation.

This publication has 0 references indexed in Scilit: