EFFECTS OF DEOXYFRENOLICIN ON ISOLATED ADIPOSE CELLS .2. LIPOLYSIS ADENOSINE 3',5'-MONOPHOSPHATE LEVELS AND COMPARISON WITH EFFECTS OF VITAMIN K5

Deoxyfrenolicin, an antifungal naphthoquinone, inhibited lipolysis induced by norepinephrine, corticotropin, caffeine or theophylline in isolated adipose cells. It was unexpectedly found that deoxyfrenolicin augmented still higher the intracellular adenosine 3', 5'-monophosphate (cyclic AMP) levels that were maximally elevated by theophylline plus norepinephrine or corticotropin. Deoxyfrenolicin was without effect on the basal levels of cyclic AMP. Vitamin K5, not vitamin K1, was found to mimic not only the effects of deoxyfrenolicin on inhibiting lipolysis and augmenting cyclic AMP levels elevated by hormones but also its effects on stimulating glucose oxidation by adipose cells. Vitamin K1 could not counteract the effects of deoxyfrenolicin or vitamin K5. No addition was observed for the effects of deoxyfrenolicin and vitamin K5. It seemed that the mode of action of deoxyfrenolicin on adipose cells is similar to that of vitamin K5, of which inhibition of electron transport or oxidative phosphorylation may be one of the sites of action. © 1969.