Role of the peripubertal pattern of FSH, LH and prolactin secretion in regulating in-vitro steroidogenesis and follicular growth within juvenile rat ovaries.
Juvenile rat ovaries were placed in perifusion culture and exposed to (1) tonic FSH (200 ng PR-1 equiv./ml), (2) LH pulses (2/h, amplitude = 80 ng RP-1 equiv./ml), (3) tonic FSH and LH pulses, (4) tonic FSH with LH mini-surges, or (5) tonic FSH with LH and prolactin mini-surges. The LH mini-surge consisted of a series of 80 ng/ml pulses (2/h) with LH increasing to 180 ng/ml for 2 h then returning to the 80 ng/ml pulses. The prolactin mini-surge consisted of a series of 15 ng/ml pulses (2/h) with prolactin increasing to 40 ng/ml for 2 h before returning to the 15 ng/ml pulses. The LH mini-surge occurred at 14:00 h daily while a prolactin mini-surge occurred at 14:00 h and 06:00 h daily. Ovaries were perifused for 0 (in-vivo control), 24 or 48 h, incubated for 1 h in hormone-free medium to assess steroid secretion and subsequently prepared for histological analysis. After a 24 h exposure to FSH, oestradiol secretion was increased, while exposure to LH pulses enhanced progesterone secretion. Treatment with FSH, LH pulses or FSH plus LH pulses decreased the number of small antral follicles by 24 h of perifusion compared to control (P less than 0.05). The LH mini-surge maintained the small and medium-sized antral follicles after 24 h and increased the number of preovulatory-sized follicles over controls by 48 h (P less than 0.05). Prolactin/LH mini-surges increased the number of preovulatory-sized follicles within 24 h.(ABSTRACT TRUNCATED AT 250 WORDS)
Peluso
J J
JJ
Department of Obstetrics and Gynecology, University of Connecticut Health Center, Farmington 06032.
D000818:Animals; D004958:Estradiol / Q000096:biosynthesis*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000494:pharmacology*; D009924:Organ Culture Techniques; D006080:Ovarian Follicle / Q000502:physiology; D010053:Ovary / Q000187:drug effects / Q000378:metabolism*; D011374:Progesterone / Q000096:biosynthesis*; D011388:Prolactin / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012741:Sexual Maturation
D011374:Progesterone; D004958:Estradiol; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone