Depletion of (/sup 3/H)methyltrienolone cytosol binding in glucocorticoid-induced muscle atrophy (42001)

Journal Article · Tue Jan 01 04:00:00 EST 1985 · Proc. Soc. Exp. Biol. Med.; (United States)

DOI:https://doi.org/10.3181/00379727-178-42001· OSTI ID:5729728

Kurowski, T T; Capaccio, J A; Chatterton, Jr, R T; Hickson, R C

The present study was undertaken to determine cytosol binding properties of (/sup 3/H)methyltrienolone, a synthetic androgen, in comparison with (/sup 3/)dexamethasone, a synthetic glucocorticoid, under conditions of glucocorticoid excess in skeletal muscle. Male hypophysectomized rats received either seven daily subcutaneous injections of cortisone acetate (CA) (100 mg x kg/sup -1/ body wt) or the vehicle, 1% carboxymethyl cellulose. Following treatment, both (/sup 3/H)dexamethansone and (/sup 3/H)methyltrienolone-receptor concentrations were decreased from those in vehicle-treated rats by more than 90 and 80%, respectively, in CA-treated animals. Scatchard analysis of (/sup 3/H)methyltrienolone binding in muscles of vehicle-treated animals became nonlinear at high concentrations of labeled ligand and were reanalyzed by a two-component binding model. The lower affinity, higher capacity component, which was attributed to binding of methyltrienolone to a dexamethasone component, which was attributed to binding of methyltrienolone to a dexamethasone component, disappeared in muscles of CA-treated rats and Scatchard plots were linear. Receptor concentrations of the higher affinity lower capacity methyltrienolone component were similar in muscles of vehicle-treated and CA-treated groups. From competition studies, the high relative specificities of glucocorticoids for (/sup 3/H)methyltrienolone binding in muscles of vehicle-treated animals were markedly reduced by CA treatment. In addition, the binding specificity data also showed strong competition by progesterone and methyltrienolone for (/sup 3/H)dexamethasone binding and estradiol-17..beta.. for (/sup 3/H)methyltrienolone binding.

• Research Organization: Univ. of Illinois, Chicago
• OSTI ID: 5729728
• Journal Information: Proc. Soc. Exp. Biol. Med.; (United States), Journal Name: Proc. Soc. Exp. Biol. Med.; (United States) Vol. 178:2; ISSN PSEBA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
AFFINITY
ANDROGENS
ANDROSTANES
ANIMALS
ATROPHY
BIOCHEMICAL REACTION KINETICS
CELL CONSTITUENTS
CHEMICAL BONDS
CORTICOSTEROIDS
CORTISONE
CYTOPLASM
DATA
DEXAMETHASONE
EXPERIMENTAL DATA
GLUCOCORTICOIDS
HORMONES
HYDROXY COMPOUNDS
INFORMATION
ISOTOPE APPLICATIONS
KETONES
KINETICS
LABELLED COMPOUNDS
LIGANDS
MAMMALS
MATHEMATICAL MODELS
MUSCLES
NUMERICAL DATA
ORGANIC COMPOUNDS
PATHOLOGICAL CHANGES
PHYSIOLOGY
PREGNANES
PROGESTERONE
RATS
REACTION KINETICS
RECEPTORS
RODENTS
SPECIFICITY
STEROID HORMONES
STEROIDS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES