Abstract
Using rats on day 17 of pregnancy, the effect of prostaglandin F2a (PGF2a) on luteal vasculature was investigated with the technique of microangiography.
1. After intravenous administration of PGF2a in doses of 50, 250μg/kg as a single injection, remarkable constriction of luteal vasculature was observed dose-dependently. The similar response was caused by noradrenaline (NA) in doses of 10 and 50μg/kg.
2. When PGF2a with doses of 5 to 100μg/kg and NA of 0.5 to 50μg/kg were administered, a rise in blood pressure were observed. Subcutaneous administration of PGF2a or NA 1 mg/kg had also similar response on blood pressure.
3. Intravenously administered PGF2a 250μg/kg and NA 50μg/kg (b. i. d.) had no effect on fetal mortality in rats. Whereas PGF2a 1.0 mg/kg (b. i. d.) administered subcutaneously was enough to induce fetal mortality in a all animals, but the same dose of NA was not.
In present report, it is suggested that PGF2a and NA suppress the luteal circulation remarkably but PGF2a only plays a role in reduction of luteal function.
