Title: Inhibitory effects of steroids on gonadotrophin secretion in the male rat.

POPLINE Document Number: 600018

Author(s):

Nelson WO
Patanelli DJ

Source citation:

Proceedings of the First International Congress of Endocrinology, Session 8h, No. 455, 1960. p. 905,

Abstract:

In assessing the capacity of a large number of steroids to inhibit gonadal function in male rats, it has been observed that the endocrine component of the testis appears to be inhibited more readily than is spermatogenesis. The compound is administered by the oral or parenteral route in 30-day-old male rats for 30 days. This method enables the inve stigators to distinguish between the inhibition of spermatogenic and endocrine functions of the testes and, by extrapolation, between the extent of inhibition of the FSH and ICSH secretory capacities of the hypophysis. Some of the compounds which appear to inhibit ICSH at a lower dose level than is required for inhibition of FSH are 17alpha-ethi nyl-5(10)-estraenolone, 17alpha-ethinyl-19-nortestosterone, 17alpha-ethi nyl-19-nortestosterone enanthate, 17alpha-ethinyl estradiol-3-methyl ether, 9alpha-bromo-11-ketoprogesterone, and 17alpha-2-methallyl-19-nortestosterone. Compounds whose androgenic activity are such that differentiation between ICSH and FSH inhibition c annot be made by this method although their inhibitory effect on total gonadotropin can be shown include testosterone propionate, methyl testosterone, methyl-19-nortestosterone, 17alpha-ethyl-19-nortestosteron e, and progesterone. In applying the findings to the female, it is suggested that the effectiveness of a compound in suppressing ovulation is not so much a factor of total gonadotropin inhibition as it is of an upset of the ICSH (or LH) and FSH balance. The FSH-LH ratio must be disturbed to a degree that follicular maturation and rupture are unable to progress normally. This would explain the observation that some relatively poor gonadotropin inhibitors, such as progesterone, have been observed to suppress ovulation.(AUTHOR'S, MODIFIED)

Keywords:

Animals, Laboratory
Gonadotropins
Follicle Stimulating Hormone
Androgens
Contraceptive Agents, Male
Conferences and Congresses
Analysis
Side Effects
Clinical Research
Research Methodology
Hormones
Endocrine System
Physiology
Biology
Gonadotropins, Pituitary
Contraceptive Agents
Contraception
Family Planning
Treatment