Abstract
Summary Hypophysectomy reduces the in vitro output of FFA by adipose tissue in response to both corticotropin and thyrotropin. Fasting slightly enhances the effects of these hormones on FFA output, but does not alter their effect on glycerol production, suggesting that the enhancement is due to decreased reesterification rather than increased lipolysis. Hypophysectomy also reduces FFA and glycerol production in response to fasting. It is suggested that the reduced fat mobilization usually found in hypophysectomized rats may be due to reduced sensitivity of adipose tissue to physiological stimuli for FFA mobilization rather than to a deficiency of lipolytic agents.