The relationship between insulin resistance and the change of cytosol free calcium concentration in gestational diabetes mellitus

To investigate the relationship between the insulin resistance (IR) and abnormalities of cellular calcium metabolism in gestational diabetes mellitus, the changes in the [Ca2+]i and the insulin receptor tyrosine kinase activity in circulating erythrocytes of 32 cases gestational diabetes were compared with those of 47 normal pregnant and 43 non pregnant women. The level of [Ca2+]i in circulating erythrocyte in gestational diabetes mellitus women was significantly higher than that in the pregnant and non pregnant women (P<0.01); but the level of insulin receptor tyrosine kinase activity was significantly decreased in gestational diabetes millitus (P<0.01). The [Ca2+ ]i in circulating erythrocytes in gestational diabetes mellitus was positively correlated with fasting blood glucose and fasting insulin, negatively with the insulin receptor tyrosine kisase activity (P<0.01); The change of [Ca2+ ]i level during the gastational period might be one of the possible factor in the insulin resistance of gestaional diabetes mellitus. (authors)