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

Abstract

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 <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.

Profiling of Tryptophan Metabolic Pathways in the Rat Fetoplacental Unit during Gestation

“…The results show that, during the prenatal period, the placenta and fetal brain are the most metabolically active organs in 5-HT degradation by MAO, followed by the intestine, lungs, and liver. These findings correspond well with reports by other groups for rats and humans, where placental MAO-A activity exceeds that of the lungs and liver [ 50 , 51 ]. Consequently, the interplay between placental and fetal MAO activity seems fundamental for regulating 5-HT circulating levels in the fetoplacental unit and wiring the placenta–brain axis for proper neurodevelopment of the fetus.…”

Quantitation of Leydig Cell in Testicular Biopsies of Gossypol Treated rats

“…Huang and Wang (1994) reported the effects of Gossypol on testosterone secretion. They have noticed a decrease in testosterone secretion, which was attributed to the contribution of adrenergic receptor inhibition in the hypothalamus by Gossypol this adrenergic receptor inhibition might decrease GnRH which leads to decrease of LH-Testosterone axis (Kono et al, 1991) Furthermore Leydig cell secretion act on the hypothalamus and pituitary gland through regulating the negative feedback mechanism of the quantity of GnRH release (West, 1982). Hul et al (1993); Comhaire (1994) Huang and wang (1994) and Zhaang et al (1994) reported that the mechanism of testosterone and estrogen releas was disrupted by Gossypol, through inhibition of hypothalamic estrogen receptor.…”