[Insulin resistance and hypertension]

In this study, we have measured plasma glucose and insulin levels at fasting and following an oral glucose load (75g) in 39 non-diabetic subjects (22 untreated hypertensive, 17 normotensive subjects). We also assessed plasma cholesterol (Ch), triglyceride (TG) levels and Na(+)-K(+)-pump activity in the membranes of their erythrocytes. Overall, hypertensive subjects have hypercholesterol, hypertriglyceride, glucose intolerance and hyperinsulinemia. These changes accorded with Syndrome X proposed by Reaven. In multivariant analysis, after correcting for age, BMI, diastolic pressure (DBP) was positively related to fasting, 1/2h insulin and insulin area under cure (AUC) (P < 0.05). Both systolic pressure (SBP) and DBP were negatively correlated to Na(+)-K(+)-pump (P < 0.01, 0.001), while Na(+)-K(+)-pump was negatively fasting, 1/2h, 1h, 2h insulin levels and insulin AUC (P < 0.05, 0.05, 0.01, 0.01, respectively). These results showed that insulin may affect Na(+)-K(+)-pump activity to develop hypertension independent of age and obese. We also postulated that insulin resistance was causal in the syndrome X, also one of factors developing coronary artery disease.