Insulin activates phospholipase C in fat cells: similarity with the activation of pyruvate dehydrogenase.
Phospholipase C (PHL-C) activity determined in homogenates of fat cells treated with physiological concentrations of insulin showed a 2-3-fold increase as compared to controls in the absence of insulin. The changes of PHL-C and pyruvate dehydrogenase (PDH) activity which was measured concomitantly exhibited very similar characteristics as to insulin sensitivity, saturability, time dependence and glucose requirement. Exogenous PHL-C as an activator of PDH in fat cells (Honeyman et al., 1983) also showed a striking similarity to insulin. Our findings strongly suggest that, in fat cells, PHL-C is susceptible to short-term activation by insulin. This effect may be relevant to the mechanism of PDH activation and perhaps to other metabolic actions of insulin.
D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D004789:Enzyme Activation / Q000187:drug effects; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology*; D010740:Phospholipases / Q000378:metabolism*; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D010738:Type C Phospholipases / Q000378:metabolism* / Q000494:pharmacology
D007328:Insulin; D011768:Pyruvate Dehydrogenase Complex; D010740:Phospholipases; D010738:Type C Phospholipases