Benzodiazepine binding sites in rat interscapular brown adipose tissue: effect of cold environment, denervation and endocrine ablations

Journal Article · Fri Jan 01 04:00:00 EST 1988 · Life Sci.; (United States)

DOI:https://doi.org/10.1016/0024-3205(88)90077-X· OSTI ID:5726852

Solveyra, C G; Romeo, H E; Rosenstein, R E; Estevez, A G; Cardinali, D P

/sup 3/H-Flunitrazepam (FNZP) binding was examined in a crude membrane fraction obtained from rat interscapular brown adipose tissue (IBAT). A single population of binding sites was apparent with dissociation constant (K/sub D/) = 0.47 +/- 0.04 uM and maximal number of binding sites (B/sub max/ = 31 +/- 5 pmol.mg prot/sup -1/. From the activity of several benzodiazepine (BZP) analogs to compete for the binding, the peripheral nature of FNZP binding was tentatively established. Similar BZP binding sites were detectable in isolated IBAT mitochondria. Exposure of rats to 4 /sup 0/C for 15 days decreased B/sub max/ significantly without affecting K/sub D/. Cold-induced decrease in B/sub max/ of BZP binding was prevented by surgical IBAT denervation. Denervation prevented or impaired the increased activity of the mitochondrial markers succinate dehydrogenase and malate dehydrogenase in IBAT of cold-exposed rats, but did not affect monoamine oxidase activity. Their results indicate that BZP binding in rat IBAT may belong to the peripheral type, is decreased by a cold environment through activation of peripheral sympathetic nerves and is affected by hypophysectomy. BZP and GDP binding in IBAT mitochondria seem not to be functionally related. 23 references, 4 figures, 3 tables.

• Research Organization: Universidad de Buenos Aires, Argentina
• OSTI ID: 5726852
• Journal Information: Life Sci.; (United States), Journal Name: Life Sci.; (United States) Vol. 42:4; ISSN LIFSA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADIPOSE TISSUE
AMINE OXIDASES
ANIMAL TISSUES
ANIMALS
BIOCHEMICAL REACTION KINETICS
BODY
BODY TEMPERATURE
CELL CONSTITUENTS
CELL MEMBRANES
CENTRAL NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM AGENTS
CONNECTIVE TISSUE
DATA
DRUGS
ENDOCRINE GLANDS
ENZYME ACTIVITY
ENZYMES
EXPERIMENTAL DATA
GLANDS
HYPOTHERMIA
INFORMATION
KINETICS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
MITOCHONDRIA
NERVOUS SYSTEM
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOIDS
ORGANS
OXIDOREDUCTASES
PROTEINS
PSYCHOTROPIC DRUGS
RATS
REACTION KINETICS
RECEPTORS
RESPONSE MODIFYING FACTORS
RODENTS
TISSUES
TRANQUILIZERS
VERTEBRATES