Differential regulation of serum immunoreactive luteinizing hormone and bioactive follicle-stimulating hormone by testosterone in early pubertal boys
| Autor: | Joanne Sonstein, Pamela R. Olton, Carol M. Foster, Vasantha Padmanabhan, Inese Z. Beitins, Morton B. Brown, Robert P. Kelch, Jeanne M. Hassing |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
Male
endocrine system medicine.medical_specialty Adolescent medicine.drug_class Endocrinology Diabetes and Metabolism Clinical Biochemistry Hypothalamus Gonadotropin-releasing hormone Biochemistry Gonadotropin-Releasing Hormone Follicle-stimulating hormone Endocrinology Hypogonadotropic hypogonadism Internal medicine medicine Humans Testosterone Infusions Intravenous Dose-Response Relationship Drug business.industry Biochemistry (medical) Puberty Age Factors Luteinizing Hormone Androgen medicine.disease Estrogen Gonadotropin Follicle Stimulating Hormone Luteinizing hormone business hormones hormone substitutes and hormone antagonists |
| Zdroj: | The Journal of clinical endocrinology and metabolism. 70(4) |
| ISSN: | 0021-972X |
| Popis: | 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) |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|