Effect of prostaglandin F2 alpha on serum prolactin and lh concentrations in male and female rats.

Abstract

Prostaglandin F2\g=a\(PGF2\g=a\) has been shown to induce prolactin release in pregnant rats (Deis, 1971; Vermouth & Deis, 1972). Treatment with PGF2\g=a may induce lactogenesis in women after early termination of pregnancy (Smith et al., 1972), accompanied by a significant increase in serum prolactin level (Yue et al., 1974). Harms et al. (1973) injected PGE1 into the third ventricle in castrated female rats and found increased plasma prolactin levels, although PGE2, PGF1\g=a\and PGF2\g=a\had no effect. Intraventricular or intravenous injection of PGE2 induced a significant rise of plasma LH. According to Batta et al. (1974), intracarotid injection of PGF2\g=a\resulted in a greater release of FSH than LH in ovariectomized rats treated with oestrogen, but had no effect on male rats. In ovariectomized rats primed with oestrogen and progesterone, PGE1, PGE2 and PGF2\g=a\caused increases in serum prolactin concentration (Sato et al., 1974a). Since in a previous study we postulated that the release of prolactin in pregnant rats after administration of PGF2iI was probably induced by a rapid decrease of plasma progesterone concentration (Vermouth & Deis, 1972), the present investigation was undertaken in order to establish the effect of PGF2c[