Insulin or increased concentration of zinc in liver, kidney or muscle does not alter the phosphoglucomutase activity in vivo.
Injection of insulin into mice and rabbit has been reported to convert the latent form of phosphoglucomutase (E X Zn) to an active form (E X Mg) without any net increase in the protein associated with this enzyme (Hashimoto et al., Biochem. Biophys. Res. Commun., 27 (1967) 369 and Peck et al., J. Biol. Chem. 242 (1971) 1160). Because the injection of Cd in rats causes a 2-fold increase in Zn concentration in the liver, it appeared that such treatment in mice would increase the concentration of the latent enzyme and thereby enhance the insulin induced activation of the enzyme. The results however show that insulin or Cd treatment, alone or in combination do not alter the concentrations of the 2 forms of enzyme in liver, kidney or muscle of normal or fasted mice. In all instances the conversion of the latent enzyme to its activated form required preincubation with a chelating agent. Fractionation of the tissue homogenates showed that upon Cd injection the concentration of Zn in the fractions of Mr less and 1000 increased 6-fold in liver and 3-fold in kidney, that in muscle remained unchanged.
Fleming
J
J
Miller
H
H
Joshi
J G
JG
D000818:Animals; D002104:Cadmium / Q000032:analysis / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology*; D007668:Kidney / Q000032:analysis* / Q000187:drug effects; D008099:Liver / Q000032:analysis* / Q000187:drug effects; D008297:Male; D051379:Mice; D009132:Muscles / Q000032:analysis* / Q000187:drug effects; D010733:Phosphoglucomutase / Q000032:analysis*; D015032:Zinc / Q000032:analysis*
D007328:Insulin; D002104:Cadmium; D010733:Phosphoglucomutase; D015032:Zinc