EFFECT OF INDOMETHACIN, EPINEPHRINE, PROSTAGLANDIN E-2 AND INSULIN ON LIPOLYSIS IN BOVINE ADIPOSE-TISSUE INVITRO

1. Fasting of ad libitum- or maintenance-fed steers for 4 to 9 days did not alter basal lipolytic rates in vitro. 2. Epinephrine stimulation of adipose tissue of fasted steers resulted in greater (P < 0.05) lipolysis than in tissue from fed steers. 3. Prostaglandin E2 (PGE2) did not alter epinephrine-stimulated lipolysis in ad libitum- or maintenance-fed cattle. 4. Indomethacin did not influence basal lipolysis, even in the presence of PGE2. 5. Insulin neither affected basal lipolysis nor inhibited dibutyl cAMP-stimulated lipolysis.