3-(4-hydroxy phenyl)-2-propenoic acid - a reproductive inhibitor in male rat.

Oral administration of 3-(4-hydroxy phenyl)-2-propenoic acid, at a dose of 50 mg/kg body weight/day (reported antiprolactin dose in rat) for 56 days, to adult male rat produces complete loss of libido, significant decrease in weight of testis and accessory sex organs, decrease in fructose content of coagulating gland and reduction in acid phosphatase activity in prostate. All these effects can be reversed by exogenous prolactin (500 micrograms/rat/day) plus testosterone propionate (200 micrograms/rat/day), but not by prolactin or testosterone alone, when administered along with the test compound for the last 28 days. Inhibitory influence of the compound over the reproductive organs is believed to be attributed primarily to the antiprolactin nature of the compound and secondarily to the significant (P less than 0.01) fall in plasma testosterone level caused by the compound.