Differential effects of insulin, antibodies against rat adipocyte plasma membranes, and other agents that mimic insulin action in rat adipocytes.
The effects of insulin and several insulin-mimetic agents on rat adipocyte D-glucose metabolism were studied in an effort to determine if any of the insulin-mimetic agents could be used to define the mechanism of insulin action. Antibodies against rat adipocyte plasma membranes have been characterized as having insulin-mimetic effects on glucose transport and these effects may be caused by divalent clustering of cell surface antigens. In contrast to insulin, antimembrane antibodies had little stimulatory effect on D-glucose conversion to lipids in isolated rat adipocytes, under conditions where both reagents stimulated D-glucose oxidation. Among other insulin-mimetic agents tested, the reagents hydrogen peroxide and concanavalin A most closely resembled insulin in their ability to increase both [14C]-CO2 and [14C]-lipid formation from [14C]D-glucose in rat adipocytes. Vitamin K5 and diamide had the unusual effect of inhibiting [1-14C]D-glucose conversion to [14C]-lipids at a concentration that gave maximal stimulation of glucose oxidation by rat adipocytes. Analysis of the lipid components into which glucose derivatives were incorporated revealed that insulin increased D-glucose incorporation into both nonesterified fatty acids and triglycerides and H2O2 and concanavalin A had similar effects. These findings argue against the possibility that insulin and the antimembrane antibodies or the insulin-mimetic agents other than H2O2 and concanavalin A share the same mechanism of action.
D000273:Adipose Tissue / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D000818:Animals; D000906:Antibodies / Q000494:pharmacology*; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D002855:Chromatography, Thin Layer; D003208:Concanavalin A / Q000494:pharmacology; D003958:Diamide / Q000494:pharmacology; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology*; D008055:Lipids / Q000096:biosynthesis; D010084:Oxidation-Reduction / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D013096:Spermine / Q000494:pharmacology; D014812:Vitamin K / Q000031:analogs & derivatives / Q000494:pharmacology; D024483:Vitamin K 3 / Q000031:analogs & derivatives*
D000906:Antibodies; D007328:Insulin; D008055:Lipids; D003958:Diamide; D003208:Concanavalin A; D014812:Vitamin K; D013096:Spermine; D024483:Vitamin K 3; D006861:Hydrogen Peroxide; D005947:Glucose; C024534:vitamin k5