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To explain the insulin resistance induced by catecholamines, we studied the tyrosine kinase activity of insulin receptors in a state characterized by elevated noradrenaline concentrations in vivo, i.e. cold-acclimation. Insulin receptors were partially purified from brown adipose tissue of 3-week- or 48 h-cold-acclimated mice. Insulin-stimulated receptor autophosphorylation and tyrosine kinase activity of insulin receptors prepared from cold-acclimated mice were decreased. Since the effect of noradrenaline is mediated by cyclic AMP and cyclic AMP-dependent protein kinase, we tested the effect of the purified catalytic subunit of this enzyme on insulin receptors purified by wheat-germ agglutinin chromatography. The catalytic subunit had no effect on basal phosphorylation, but completely inhibited the insulin-stimulated receptor phosphorylation. Similarly, receptor kinase activity towards exogenous substrates such as histone or a tyrosine-containing copolymer was abolished. This inhibitory effect was observed with receptors prepared from brown adipose tissue, isolated hepatocytes and skeletal muscle. The same results were obtained on epidermal-growth-factor receptors. Further, the catalytic subunit exerted a comparable effect on the phosphorylation of highly purified insulin receptors. To explain this inhibition, we were able to rule out the following phenomena: a change in insulin binding, a change in the Km of the enzyme for ATP, activation of a phosphatase activity present in the insulin-receptor preparation, depletion of ATP, and phosphorylation of a serine residue of the receptor. These results suggest that the alteration in the insulin-receptor tyrosine kinase activity induced by cyclic AMP-dependent protein kinase could contribute to the insulin resistance produced by catecholamines.
J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
November 1983,
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J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
February 1986,
The Biochemical journal,
J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
November 1987,
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J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
January 1980,
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J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
March 1972,
Israel journal of medical sciences,
J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
January 1995,
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J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
May 1980,
European journal of pharmacology,
J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
August 1989,
FEBS letters,
J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
February 1978,
Molecular and cellular biochemistry,
J F Tanti, and
T Grémeaux, and
N Rochet, and
E Van Obberghen, and
Y Le Marchand-Brustel
December 1981,
FEBS letters,
