EXPRESSION OF A 10.5 KDA INHIBIN IN THE ENDOMETRIUM OF BONNET MONKEY ON TREATMENT WITH AN ANTIPROGESTIN-ZK-98,299 - AN IMMUNOCYTOCHEMICAL STUDY

Immunocytochemical localization of inhibin was carried out in paraffin embedded tissue sections of the control and antiprogestin (ZK 98.299) -treated bonnet monkey endometrium using polyclonal antibodies generat ed against human seminal plasma inhibin (10.5 kDa). The study shows th at administration of low doses (5 mg/week) of antiprogestin results in an increase in the expression of inhibin by the endometrium. Treatmen t with higher doses (20 mg/week) caused a decrease in the expression. Since treatment with higher doses also caused atropic changes in the e ndometrium, the decrease in inhibin could be the result of morphologic al damage to the endometrium rather than the effects of antiprogestin on the expression of inhibin. The potential involvement of endometrial inhibin in the process of nidation is speculated.