Effects of luteinizing hormone on superovulatory and steroidogenic responses of rat ovaries to infusion with follicle-stimulating hormone.

摘要: Immature female rats were infused s.c. continuously over a 60-h period with partially purified porcine pituitary follicle-stimulating hormone (FSH) preparation having FSH activity 4.2 x NIH-FSH-S1 and luteinizing (LH) 0.022 NIH-LH-S1. High rates of superovulation observed in receiving 1 U FSH/day, 69 +/- 11 oocytes/rat recovered as cumulus-enclosed oocytes from oviducts on Day (equivalent to the day estrus). Addition LH FSH, at dosages equivalent 2.5-100 micrograms/day NIH-LH-S1 equivalents (2.5-100 mU) resulted dose-related inhibition superovulation, reaching nadir 15 7 50 mU LH/day together FSH/day. At two highest doses, 100 mU/day, ovulation was advanced so that 12 3 4 oocytes, respectively, these flushed morning 0, compared none alone. Ovarian steroid concentrations (ng/mg) 0 alone progesterone, 0.50 0.13; testosterone, 0.16 0.08; androstenedione, 0.06; estradiol, 0.23 0.05. On 1, ovarian progesterone had risen 3.30 0.33 ng/mg, whereas fallen essentially undetectable levels. infusion increases, all four steroids up dosage 25 LH/day. higher dosages, androgens estradiol fell markedly, while continued increase. Histological examination ovaries revealed increases extent luteinization granulosa cells follicles retained both Days those These findings indicate elevated levels doses due premature follicles, thus preventing ovulation. lower no sign (based histologic or steroidogenic criteria) evident, suggesting decreased follicular maturation and/or increased atresia rather than without ovulation.(ABSTRACT TRUNCATED AT 400 WORDS)