[Endogenous digitalis-like substance in relation to glycemia and insulinemia]

The digitalis-like substance (DLS), insulin resistance, and hyperglycemia are ascribed important roles in the pathogenesis of essential hypertension. The relationship between DLS and glycemia (insulinemia) was investigated in the present study. The levels of glycemia, insulinemia and DLS were measured during oral glucose load in a group of 18 subjects with various blood pressure values. Fasting levels of glycemia and insulinemia were in each subject within the physiological range and no correlation was found to exist between the fasting levels of DLS and glycemia (insulinemia). One hour after oral glucose load the increase of glycemia and insulinemia was significantly higher in the group of subjects with SBP > 140 and/or DBP > 90 mmHg than in normotensive subjects (p < 0.001). The increase in glycemia (insulinemia) was followed by a decrease of DLS. This contrary trend could be expressed as a significant inverse correlation between the change in plasma DLS and the change in glycemia (r = -0.660 p = 0.0039), and also between the change in plasma DLS and the change insulinemia (r = -0.687 p = 0.0023). These findings are assumed to suggest certain mechanisms involved in the pathophysiology of essential hypertension. (Tab. 3, Fig. 2, Ref. 20.)