The effect of manganese on lipogenesis, lipolysis, adenosine 3',5' cyclic monophosphate and cyclic nucleotide phosphodiesterase activity in adipocytes from NZY mice.
The insulin-like action of Mn2+ was investigated in adipocytes isolated from male mice of the NZY strain. In agreement with previous reports Mn2+ was found to stimulate both the oxidation of [U-14C]glucose to CO2 and the incorporation of [U-14C]glucose into total lipid and fatty acid, and to inhibit lipolysis stimulated by epinephrine, cyclic AMP or theophylline. The maximum effect of Mn2+ was greater than that of a maximal concentration of insulin and when both agents were present in these concentrations the effect was similar to that observed with Mn2+ alone. Mn2+ lowered the level of cyclic AMP in adipocytes incubated with isoproterenol. The effect was seen as early as 1 minute and it was greater than a maximal concentration of insulin. When Mn2+ was added to suspensions of adipocytes it increased the activity of the membrane-bound low Km cyclic nucleotide phosphodiesterase in subsequently prepared homogenates. The enzyme was stimulated 1.8-fold by Mn2+ compared with a 1.7-fold stimulation by insulin and a 2-fold stimulation in the presence of both Mn2+ and insulin.
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000378:metabolism*; D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D002413:Cations, Divalent / Q000494:pharmacology; D002462:Cell Membrane / Q000201:enzymology; D000242:Cyclic AMP / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D007328:Insulin / Q000494:pharmacology; D007700:Kinetics; D050356:Lipid Metabolism; D008297:Male; D008345:Manganese / Q000494:pharmacology*; D051379:Mice
D002413:Cations, Divalent; D007328:Insulin; D008345:Manganese; D000242:Cyclic AMP; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D005947:Glucose