RT Journal Article SR Electronic T1 THE EFFECT OF SOME SEDATING AGENTS ON CALORIGENESIS AND ITS RESPONSES TO 2,4-DINITROPHENOL AND l-THYROXINE IN RATS JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 514 OP 519 VO 177 IS 3 A1 FRANCES P. PETRAITIS A1 FREDERIC L. HOCH YR 1971 UL http://jpet.aspetjournals.org/content/177/3/514.abstract AB A sedating agent was sought which would eliminate spontaneous activity in rats without otherwise perturbing oxidative metabolism as measured by the metabolic rate (O2 consumption). The criteria were that it be effective long enough to permit studies of calorigenesis over a period of two hours, and that it leave unaltered the separate and combined calorigenic effects of 2,4-dinitrophenol and l-thyroxine. Sodium pentobarbital (40 µg/g s.c.) and urethane (1250 µg/g s.c.) did not satisfy these criteria; pretreatment with pentobarbital lowered the initial metabolic rate 34%, accentuated the calorigenic response to l-thyroxine, and resulted in a 50% mortality; pretreatment with urethane depressed the metabolic rate 16%, apparently abolished l-thyroxine-induced calorigenesis, and made dinitrophenol lethal in 40% of the animals. Diazepam (40 µg/g s.c., injected as a 10 mg/ml solution in 30% dimethyl sulfoxide, 45% propylene glycol, 10% ethanol and 15% water) lowered the metabolic rate 10% (as is found with sleep) and did not interfere with dinitrophenol- and l-thyroxine-induced calorigenesis. The measurements of metabolic rates alter pretreatment with diazepam were more precise, due to the elimination of spontaneous movements. © 1971 by The Williams & Wilkins Co.