Biomaterial Database

Serum testosterone and testicular response to HCG in young and aged male rats. 1978

A E Miller, and G D Riegle

Serum testosterone and testicular response to HCG was measured in young (3 - 6 mo) and aged (20 - 30 mo) male Long-Evans rats. Serum testosterone was measured by radioimmunoassays on serial blood samples taken before and after injections of HCG. Control group serum testosterone concentrations were lower in aged compared to young groups. Intravenous injection of 1, 5, and 20 IU of HCG increased serum testosterone in both age groups and testosterone remained elevated throughout the 150-min sampling interval. The increase in serum testosterone concentrations following acute HCG stimulation was greater in young than in aged rats. Serum testosterone concentrations and testicular response to intravenous HCG injections were increased to similar levels in young and aged male rats following 7 days of daily subcutaneous injections of 5 IU of HCG/100 gm bw. These data suggest that while testicular secretion and responsiveness is reduced with age, the aged male rat retains the capacity to secrete more testosterone than it normally maintains.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D006063	Chorionic Gonadotropin	A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).	Chorionic Gonadotropin, Human,HCG (Human Chorionic Gonadotropin),Biogonadil,Choriogonadotropin,Choriogonin,Chorulon,Gonabion,Human Chorionic Gonadotropin,Pregnyl,Gonadotropin, Chorionic,Gonadotropin, Human Chorionic
D000375	Aging	The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.	Senescence,Aging, Biological,Biological Aging
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013737	Testis	The male gonad containing two functional parts: the SEMINIFEROUS TUBULES for the production and transport of male germ cells (SPERMATOGENESIS) and the interstitial compartment containing LEYDIG CELLS that produce ANDROGENS.	Testicles,Testes,Testicle
D013739	Testosterone	A potent androgenic steroid and major product secreted by the LEYDIG CELLS of the TESTIS. Its production is stimulated by LUTEINIZING HORMONE from the PITUITARY GLAND. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to DIHYDROTESTOSTERONE or ESTRADIOL.	17-beta-Hydroxy-4-Androsten-3-one,17-beta-Hydroxy-8 alpha-4-Androsten-3-one,8-Isotestosterone,AndroGel,Androderm,Andropatch,Androtop,Histerone,Sterotate,Sustanon,Testim,Testoderm,Testolin,Testopel,Testosterone Sulfate,17 beta Hydroxy 4 Androsten 3 one,17 beta Hydroxy 8 alpha 4 Androsten 3 one,8 Isotestosterone
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus