title: Immunoreactive inhibin in follicular fluid is related to meiotic stage of the oocyte during final maturation of the porcine follicle.
abstract: The concentration and content of inhibin was determined in individual porcine follicles from gilts ovariectomized at various times after the onset of estrus. In one experiment, gilts (n = 5) were ovariectomized at 0, 10, or 20 hr after the onset of estrus and the follicular fluids from all large follicles individually aspirated. In a second experiment, gilts (n = 6) were ovariectomized at 21, 24, 27, 30, or 34 hr after the onset of estrus; follicular fluids were aspirated; and each oocyte was stained and evaluated for cytogenetic stage of meiotic maturation. Inhibin was determined in diluted follicular fluids with a radioimmunoassay based on a synthetic peptide replica of part of the alpha subunit of porcine inhibin. Inhibin values were expressed in terms of thousands of units (kU) of a World Health Organization inhibin standard (86/690). Concentration of inhibin did not vary among hours (overall mean 248 kU/ml). Total follicular content of inhibin also was not different among hours (overall mean 57 kU/follicle). When follicles were classified on the basis of the maturation of the oocyte, significant differences were found. Concentration of inhibin in follicles with a germinal vesicle-stage oocyte was 138 kU/ml, whereas follicles with more mature oocytes had concentrations of between 204 and 254 kU/ml. Follicular content of inhibin showed a similar pattern with 34.9 kU/follicle at germinal vesicle stage, increasing to 42.5-56.1 kU/follicle at later stages. Quantities of inhibin were also negatively skewed and were positively correlated to follicular content of estradiol and dermatan sulfate.
authors.affiliation: Department of Obstetrics and Gynecology, Ohio State University, Columbus 43210.
authors.forename: K F
authors.initials: KF
authors.lastname: Miller
authors.forename: S
authors.initials: S
authors.lastname: Xie
authors.forename: W F
authors.initials: WF
authors.lastname: Pope
mesh_terms: D000818:Animals; D005260:Female; D015571:Follicular Fluid / Q000378:metabolism*; D007265:Inhibins / Q000378:metabolism*; D008540:Meiosis; D009865:Oocytes / Q000166:cytology*; D010052:Ovariectomy; D011863:Radioimmunoassay; D013552:Swine
chemical_list: D007265:Inhibins