Effect of local GABA administration on rat ovarian blood flow, and on progesterone and estradiol secretion

The effect of gamma-aminobutyric acid (GABA)--superfused onto the surface of the ovary--on ovarian blood flow and on estradiol-17-beta (E2) and progesterone (P) secretion was studied in anaesthesized, pseudopregnant rats. GABA, 0.5 mumol per 50 microliter per animal, significantly reduced the blood pressure in the femoral artery, increased ovarian blood flow, enhanced the rate of E2 release and markedly decreased P secretion. The present findings indicate that local GABAergic mechanisms may be involved in the regulation of ovarian blood flow and hormone secretion.