regulation of lipolysis and cyclic amp synthesis through energy supply in isolated human fat cells the effects of glucose and of various inhibitors of glycolysis or of oxidative phosphorylation on stimulated lipolysis and on intracellular cyclic amp and atp levels were investigated in isolated human fat cells the glycolysis inhibitors naf and monoiodoacetate inhibited epinephrine or theophyllinestimulated lipolysis and parallely reduced the intracellular cyclic amp and atp levels however neither naf nor monoidoacetate significantly affected dibutyryl cyclic ampinduced lipolysis removal of glucose from the medium also reduced the rate of epinephrinestimulated lipolysis and the intracellular cyclic amp and atp levels but failed to modify the lipolytic activity of dibutyryl cyclic amp the oxidative phosphorylation inhibitors antimycin a and under fixed conditions 24dinitrophenol also strongly decreased the adipocyte cyclic amp and atp levels but inhibited as well the rate of epinephrine and of dibutyryl cyclic ampinduced lipolysis nethylmaleimide a mixed glycolysis and oxidative phosphorylation inhibitor not only reduced the intracellular cyclic amp and atp levels and epinephrine or theophyllineinduced lipolysis but also that stimulated by dibutyryl cyclic amp when glycolysis was almost fully inhibited human fat cells were insensitive to epinephrine but remained fully responsive to dibutyryl cyclic amp these results showing a relationship between atp availability cyclic amp synthesis and lipolysis suggest a different atp requirement for cyclic amp synthesis and triacylglycerol lipase activation a difference which could explain why atp issued from glucose breakdown appears to be a determinant factor for cyclic amp synthesis but not for triacylglycerol lipase activation in human fat cells