THE IMMUNOHISTOCHEMICAL CHANGE OF PITUITARY GONADOTROPIC CELLS IN THE PREGNANT RATS AFTER INJECTION OF A HIGH DOSAGE OF LUTEINIZING HORMONE RELEASING HORMONE ANALOGUE (LHRH-A) / 解剖学报

ABSTRACT

The specific anti-rat LH, anti-rat FSH and anti-hCG sera were used in the peroxidase antiperoxidase (PAP) immunohistochemical method to observe the change of pituitary gonadotropic cells in pregnant rats after being injected by a high dosage of LHRH-A. It was observed that 24 hrs after injection the immunohistochemical reaction of gonadotropic cells weakened strikingly; 48 hrs after injection the immunohistochemical reaction began to recover; and 168 hrs after injection, the recovery was still in progress. The number of LH cells of different immunoreactive intensity and their percentage in total LH cells of the control and experimental groups were calculated and tested by statistical method. It was found that the results were the same as the above. Our observations support the view that the high dosage of LHRH-A can stimulate gonadotropic cells in rat to release a great amount of LH rapidly. It inhibits the synthesis of progesterone in the ovary of pregnant rat and results in termination of pregnancy. Moreover it is believed that the effect of high dosage of LHRH-A on the secretory function of gonadotropic cells can recover themseleves.