Plasma prorenin response to XXXX chorionic gonadotropin in ovarian-hyperstimulated @entity1 : correlation with the number of ovarian follicles and steroid hormone concentrations.

@entity1 @entity172 @entity1420 @entity53 @entity916 @entity1173
Plasma prorenin and active @entity916 were measured before and after @entity1 chorionic gonadotropin (hCG) administration in two groups of @entity1 undergoing ovarian stimulation for 4-6 days with follicle-stimulating hormone alone or in combination with luteinizing hormone, for in vitro fertilization. Baseline total plasma @entity916 (prorenin plus active @entity916 ; n = 12) averaged 25 +/- 8 ng/ml per hr (mean +/- SD). Total @entity916 did not change during ovarian stimulation but it increased to 46 +/- 16 ng/ml per hr (P less than 0.05) 1 or 2 days later, just before hCG administration. Thirty-six hours after hCG administration, just before laparoscopy and egg retrieval, total @entity916 was 123 +/- 97 ng/ml per hr; a peak of 182 +/- 143 ng/ml per hr occurred 2-6 days later--i.e., during the luteal phase of the menstrual cycle. In eight of the @entity1 who did not conceive, total @entity916 returned to baseline 14 days after hCG administration. In four who conceived, a nadir was reached (57 +/- 13 ng/ml per hr) 8-12 days after hCG administration and then total @entity916 increased again as the plasma beta hCG measurement began to rise. By day 16 it averaged 225 +/- 157 ng/ml per hr. In a second group of five @entity1 active @entity916 and prorenin were measured separately. Active @entity916 comprised less than 20% of the total @entity916 at all times. It was unchanged until day 4 after hCG administration and then increased significantly only when plasma @entity1420 was high. Thus, the initial response to hCG was entirely due to an increase in prorenin. A highly significant correlation was observed between the number of follicles and the total @entity916 increases on the day of @entity1173 (r = 0.93, P less than 0.001) and at the peak (r = 0.89, P less than 0.001). After hCG administration, a temporal relationship was observed between the rise in total @entity916 and plasma @entity53 and @entity1420 levels. These results demonstrate that plasma prorenin increases markedly after administration of hCG and that the rise is directly related to the number of ovarian follicles and to plasma @entity172 and @entity1420 levels. The findings suggest that prorenin is produced by the mature ovarian follicle and by the corpus luteum in response to gonadotropin stimulation.
