ADRENALECTOMY REVERSES PREEXISTING OBESITY IN ADULT GENETICALLY-OBESE(OB OB) MICE/

OBJECTIVE: To determine if adrenalectomy would reverse the pre-existin g gross obesity, characteristic of adult genetically obese (ob/ob) mic e. DESIGN: Adult (12 wk old) female ob/ob mice were adrenalectomized a nd fed a stock diet for 6 or 14 weeks. They were housed at 23-25 degre es C or 33 degrees C. Food intake and total body energy were determine d. RESULTS : Adrenalectomy abolished the hyperphagia characteristic of ob/ob mice. Adrenalectomized ob/ob mice consumed 8-17% less food than intact lean mice. Adrenalectomized ob/ob mice housed at 23-25 degrees C lost 55% of their pre-existing body energy within 6 weeks after sur gery and 75% of their body energy within 14 weeks after surgery. At 14 weeks after surgery, body weights and body energy content of the adre nalectomized ob/ob mice were comparable with values for intact lean mi ce. Intact ob/ob mice pair-fed to adrenalectomized ob/ob mice lost onl y half as much body energy as the adrenalectomized ob/ob mice did, ind icating that adrenalectomy not only diminished food intake in ob/ob mi ce but also increased their energy expenditure per unit food consumed. Adrenalectomized ob/ob mice housed at 33 degrees C lost only half as much body energy in 6 weeks as did mice housed at 23-25 degrees C. CON CLUSION: Adrenalectomy reverses the gross obesity characteristic of ad ult ob/ob mice by abolishing their hyperphagia and increasing their en ergy expenditure per unit food consumed.