Effects of ovine follicular fluid on plasma LH and FSH secretion in ovariectomized ewes to indicate the site of action of inhibin

Abstract

Ovariectomized ewes were given 2 ml s.c. injections of ovine follicular fluid (oFF) (N = 3) or serum (N = 3) and blood samples were collected each day for 3 days. Follicular fluid caused a significant (P < 0.005) reduction in FSH within 1 day, but did not affect mean LH values. Two groups of 3 ewes were treated as above but sampled intensively (each 10 min for 6 h) on Days 1 (before treatment) and 4; mean plasma FSH concentration and plasma LH pulse frequency and amplitude were ascertained. Significant (P < 0.005) reduction of FSH concentration was seen in the oFF-treated ewes. A non-specific reduction in LH pulse amplitude, but not pulse frequency, was noted in the control ewes. This experi..