TY - JOUR
T1 - Insulin binding and sensitivity in rat skeletal muscle
T2 - Effect of starvation
AU - Brady, L. J.
AU - Goodman, M. N.
AU - Kalish, F. N.
AU - Ruderman, N. B.
PY - 1981/2
Y1 - 1981/2
N2 - In contrast to adipose tissue and heart, the in vitro sensitivity of skeletal muscle to insulin is enhanced by starvation. To determine the basis for this, insulin binding and its ability to stimulate glucose metabolism were examined in the incubated rat soleus. In solei from 50-g rats, starvation for 48 h enhanced insulin binding by 50-100% at concentrations of 100 ng/ml or less. Starvation also resulted in higher basal and insulin-stimulated rates of glycogen synthesis, glycolysis, and glucose uptake. The enhanced effect of insulin only occurred at concentrations less than 50-75 ng/ml, in keeping with the increased binding of insulin in this concentration range. On the other hand, under conditions in which binding at equilibrium was the same, glucose uptake was still higher in the starved group, suggesting that some postreceptor event may have been more sensitive to insulin. These studies confirm that the in vitro sensitivity of rat skeletal muscle to insulin is enhanced by 48 h of starvation. They suggest that this is due at least partially to an increase in insulin binding at physiological concentrations.
AB - In contrast to adipose tissue and heart, the in vitro sensitivity of skeletal muscle to insulin is enhanced by starvation. To determine the basis for this, insulin binding and its ability to stimulate glucose metabolism were examined in the incubated rat soleus. In solei from 50-g rats, starvation for 48 h enhanced insulin binding by 50-100% at concentrations of 100 ng/ml or less. Starvation also resulted in higher basal and insulin-stimulated rates of glycogen synthesis, glycolysis, and glucose uptake. The enhanced effect of insulin only occurred at concentrations less than 50-75 ng/ml, in keeping with the increased binding of insulin in this concentration range. On the other hand, under conditions in which binding at equilibrium was the same, glucose uptake was still higher in the starved group, suggesting that some postreceptor event may have been more sensitive to insulin. These studies confirm that the in vitro sensitivity of rat skeletal muscle to insulin is enhanced by 48 h of starvation. They suggest that this is due at least partially to an increase in insulin binding at physiological concentrations.
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U2 - 10.1152/ajpendo.1981.240.2.e184
DO - 10.1152/ajpendo.1981.240.2.e184
M3 - Article
C2 - 7008629
AN - SCOPUS:0019532517
SN - 0193-1849
VL - 240
SP - 184
EP - 190
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
IS - 2
ER -