TY - JOUR
T1 - Regulation of the androgen and glucocorticoid receptors in rat and mouse skeletal muscle cytosol
AU - Dahlberg, Erik
AU - Snochowski, Marek
AU - Gustafsson, Jan-Ake
PY - 1981/1/1
Y1 - 1981/1/1
N2 - Using a charcoal technique, we determined the relative binding affinity of some anabolic compounds for the androgen and glucocorticoid receptors in cytosol from rat skeletal muscle. Only a few of the compounds analyzed competed for the receptor-binding sites. The androgen and glucocorticoid receptors were analyzed in rat and mouse skeletal muscle cytosols by Scatchard analysis. In rats grouped according to sex and age, the cytosolic protein content was about the same in all groups, but the DNA content decreased with increased weight of the animal regardless of sex (male, female, or castrated male). The glucocorticoid receptor did not differ in concentration (2-3 pmol/g tissue) or ligand affinity (K(d), 10-40 nM) among the groups, but the androgen receptor concentration decreased with increased weight and age of the animals, more in the case of males than in the case of females or castrates. The K(d) for the androgen receptor increased with age in males but was constantly about 0.2 nM for castrates or females. In adult intact rats, the androgen and glucocorticoid receptor concentrations in muscle cytosol from females were about 100 and 3000 fmol/g tissue, respectively, the corresponding values for males being about 50 and 2000 fmol/g tissue, respectively. Short term castration or adrenalectomy increased the concentration of and ligand affinity for the androgen and glucocorticoid receptors, respectively. After long term castration of male rats, the concentration of both receptors increased during 5 weeks to about the female level, only to decrease later. Neonatally castrated male rats had about the same androgen receptor concentrations and K(d) values as female rats. Female mice had higher androgen receptor concentrations (~700 fmol/g tissue) than rats. Intact male mice had about 200 fmol androgen receptor-binding sites/g tissue, and the same amount was found in mice bearing the testicular feminization (Tfm) mutant gene. In summary, the concentrations of androgen and glucocorticoid receptors in rat skeletal muscle are regulated at least by the testes. The presence of androgen receptors in skeletal muscle from Tfm mice is surprising and may motivate a reinvestigation of the regulation of androgen receptors in Tfm animals.
AB - Using a charcoal technique, we determined the relative binding affinity of some anabolic compounds for the androgen and glucocorticoid receptors in cytosol from rat skeletal muscle. Only a few of the compounds analyzed competed for the receptor-binding sites. The androgen and glucocorticoid receptors were analyzed in rat and mouse skeletal muscle cytosols by Scatchard analysis. In rats grouped according to sex and age, the cytosolic protein content was about the same in all groups, but the DNA content decreased with increased weight of the animal regardless of sex (male, female, or castrated male). The glucocorticoid receptor did not differ in concentration (2-3 pmol/g tissue) or ligand affinity (K(d), 10-40 nM) among the groups, but the androgen receptor concentration decreased with increased weight and age of the animals, more in the case of males than in the case of females or castrates. The K(d) for the androgen receptor increased with age in males but was constantly about 0.2 nM for castrates or females. In adult intact rats, the androgen and glucocorticoid receptor concentrations in muscle cytosol from females were about 100 and 3000 fmol/g tissue, respectively, the corresponding values for males being about 50 and 2000 fmol/g tissue, respectively. Short term castration or adrenalectomy increased the concentration of and ligand affinity for the androgen and glucocorticoid receptors, respectively. After long term castration of male rats, the concentration of both receptors increased during 5 weeks to about the female level, only to decrease later. Neonatally castrated male rats had about the same androgen receptor concentrations and K(d) values as female rats. Female mice had higher androgen receptor concentrations (~700 fmol/g tissue) than rats. Intact male mice had about 200 fmol androgen receptor-binding sites/g tissue, and the same amount was found in mice bearing the testicular feminization (Tfm) mutant gene. In summary, the concentrations of androgen and glucocorticoid receptors in rat skeletal muscle are regulated at least by the testes. The presence of androgen receptors in skeletal muscle from Tfm mice is surprising and may motivate a reinvestigation of the regulation of androgen receptors in Tfm animals.
UR - http://www.scopus.com/inward/record.url?scp=0019451266&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0019451266&partnerID=8YFLogxK
U2 - 10.1210/endo-108-4-1431
DO - 10.1210/endo-108-4-1431
M3 - Article
C2 - 6970661
AN - SCOPUS:0019451266
VL - 108
SP - 1431
EP - 1440
JO - Endocrinology
JF - Endocrinology
SN - 0013-7227
IS - 4
ER -