Gossypol effects on monoamine oxidase (MAO) activity in several organs of term rats.

In order to study the effect of gossypol on the monoamine oxidase (MAO) activity in pregnant rat organs, 20 day pregnant rats were sacrificed, and MAO activity/0.02 g tissue of several organs and total MAO activity/organ, were determined. The control group (n = 5) were injected with vehicle intramuscularly on the 17th, 18th and 19th day of pregnancy, and the gossypol treated group (n = 4) were injected with gossypol acetic acid (GAA) (25 mg/kg of body weight) intramuscularly on the 17th, 18th and 19th day and were decapitated on the 20th day of pregnancy. Maternal liver, uterus, placenta, and fetal liver were collected and examined. In placenta, total MAO activity/organ was significantly (p less than 0.05) lower in the GAA treated group than that in the control group. However, in maternal liver, uterus and fetal liver, there was no significant difference in total MAO activity/organ between the two groups. There was no significant difference in MAO activity/0.02 g tissue (specific activity), weight of organ, protein weight/organ and protein/g tissue between the two groups in maternal liver, uterus, placenta and fetal liver. These results suggest that, after intramuscular injection of GAA, total MAO activity/organ in the placenta of pregnant rats might decrease significantly.