Appearance of the uterine specific proteins following induction of ovulation in prepubertal gilts.

Abstract

The effects of age and human chorionic gonadotropin (HCG) treatment upon the quantitative and qualitative uterine specific protein secretory patterns were determined during the induced cycle of non-mated prepubertal gilts. Twelve gilts each at 3, 4 and 5 months of age were allotted randomly to one of two treatment groups prior to induction of ovulation: 1) saline-treated; 2) HCG-treated. Ovulation was induced with HCG following treatment with pregnant mare serum gonadotropin (PMSG), and the day of ovulation was designated as day 1. All gilts received either .9% NaCl or 400 IU of HCG daily from days 12 through 16 of the induced cycle. All saline and HCG-treated gilts were laparotomized and uteri infused with phosphate-buffered saline on day 16 to obtain uterine protein secretions. The plasma progesterone level as measured by radioimmunoassay on day 11 and the observations made at laparotomy indicated that only one gilt 3 months of age failed to ovulate. The number of CL, plasma progesterone, total recoverable uterine protein and uterine specific protein as measured on day 16 were significantly affected by age of gilt. These same characteristics, excluding uterine specific protein, were additionally affected by the HCG treatment. Total recoverable uterine protein and uterine specific protein in saline and HCG-treated gilts at 3, 4 and 5 months of age were 6.3 and 1.5, 10.4 and 2.8; 38.8 and 15.2, 51.6 and 15.9; 20.4 and 7.7, 47.8 and 14.6 mg, respectively.