Evaluation of the effects of forskolin and the antilipolytic agents insulin and nicotinic acid on cyclic AMP levels in rat epididymal adipocytes.
The effects of forskolin and the antilipolytic agents nicotinic acid and insulin on cAMP accumulation in rat epididymal adipocytes were evaluated. Forskolin markedly stimulated cAMP accumulation in adipocytes of the rat. Addition of epinephrine to cells treated with forskolin acted synergistically to increase the cAMP accumulation 4-fold when compared with cells treated with forskolin alone. Analysis of the forskolin dose-response kinetics indicated a dose-dependent increase in the accumulation of cAMP. The presence of 1-methyl-3-isobutylxanthine caused a shift in the forskolin dose-response to lower concentrations. In contrast, addition of nicotinic acid to cells treated with 1-methyl-3-isobutylxanthine caused a shift in the forskolin dose-response to higher concentrations. Preincubation of cells with adenosine deaminase did not alter the forskolin dose-response curve but potentiated its effect. Forskolin stimulation of cAMP accumulation in adipocytes was inhibited by the antilipolytic agents nicotinic acid and insulin.
S H
SH
Fatemi
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000243:Adenosine Deaminase / Q000378:metabolism; D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D005576:Colforsin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000242:Cyclic AMP / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D007328:Insulin / Q000494:pharmacology*; D007700:Kinetics; D009525:Niacin / Q000494:pharmacology*; D051381:Rats
D007328:Insulin; D005576:Colforsin; D009525:Niacin; D000242:Cyclic AMP; D000243:Adenosine Deaminase; D015056:1-Methyl-3-isobutylxanthine