| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Journal of Clinical Endocrinology & Metabolism, Vol 70, 1082-1089, Copyright © 1990 by Endocrine Society
ARTICLES |
JM Hassing, V Padmanabhan, RP Kelch, MB Brown, PR Olton, JS Sonstein, CM Foster and IZ Beitins
Department of Pediatrics, University of Michigan Hospitals, Ann Arbor 48109-0718.
The microheterogeneity and bioassayable activity of serum FSH (B-FSH) can be regulated by exogenous GnRH in boys with idiopathic hypogonadotropic hypogonadism and by estrogen in a women with gonadal dysgenesis, presumably via hormonally mediated changes in the degree of FSH glycosylation. To test the hypothesis that testosterone (T) regulates the circulating forms of B-FSH, we raised the serum T levels of early pubertal boys to adult levels. In this model, high dose T inhibits the pubertal nocturnal augmentation of LH secretion, apparently through decreased GnRH secretion. This model allowed us to test a second hypothesis, that B-FSH is a sensitive indicator of hypothalamic GnRH release. The boys were studied on two consecutive weekends, during which they received either saline (S) or T infusions. Beginning at noon on the study day, after an overnight acclimatization, the boys received either S or T at 33% or 100% of the adult male production rate. Blood was sampled from 2000-0800 at 10-min intervals for immunoactive LH and FSH (I-FSH) and for B-FSH, as determined by the in vitro Sertoli cell aromatase induction assay, and at 30-min intervals for T. Gonadotropin levels were analyzed as mean hourly or 3- h concentrations and as pulse profiles by two established objective peak detection programs, Cluster and Detect. During S treatment, mean LH increased after the onset of sleep (P = 0.0006) and, after plateauing for several hours, declined to baseline in the early morning hours. Mean levels of B-FSH were also minimally (but significantly) increased after the onset of sleep (P = 0.046) and paralleled the decline noted for LH. Mean levels of I-FSH did not demonstrate a diurnal rhythm. The effect of T was gonadotropin specific. High dose T abolished the nocturnal elevation in mean LH concentrations, but had no effect on the nocturnal elevation of B-FSH (P less than 0.05) or on I- FSH levels. The LH pulse frequency was greatest from 2300-0450 h, during S treatment (P = 0.016). The pulse frequency of B-FSH was also minimally increased after the onset of sleep (P = 0.045). The T infusion abolished the nocturnal increase in LH pulse frequency, without an effect on B-FSH pulse frequency. B-FSH pulse frequency exceeded LH pulse frequency during S treatment (8.0 +/- 0.7 pulses/12 h vs. 5.5 +/- 0.4), and B-FSH pulses persisted throughout the night. The pulse amplitudes of LH and B-FSH were not affected by T.(ABSTRACT TRUNCATED AT 400 WORDS)
This article has been cited by other articles:
![]() |
D. J. Phillips, K. Albertsson-Wikland, K. Eriksson, and L. Wide Changes In the Isoforms of Luteinizing Hormone and Follicle-Stimulating Hormone during Puberty In Normal Children J. Clin. Endocrinol. Metab., September 1, 1997; 82(9): 3103 - 3106. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. D. Veldhuis, A. Iranmanesh, E. Samojlik, and R. J. Urban Differential Sex Steroid Negative Feedback Regulation of Pulsatile Follicle-Stimulating Hormone Secretion in Healthy Older Men: Deconvolution Analysis and Steady- State Sex-Steroid Hormone Infusions in Frequently Sampled Healthy Older Individuals J. Clin. Endocrinol. Metab., April 1, 1997; 82(4): 1248 - 1254. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |