[Angiotensin converting enzyme inhibitors increase insulin sensitivity in offspring of families with hypertension even after active interventions. Results of a clamp study].

BACKGROUND

Altered insulin sensitivity is the basis for the syndrome of insulin resistance generally known as metabolic syndrome. Its importance is due to the cumulation of a number of risk factors of IHD. The familial disposition for the syndrome may be the cause of medical complications also in families of hypertensive patients. The objective of the study was to provide evidence of the possible change of insulin sensitivity in a group of middle-aged men from families with disposition for hypertension two years regime therapy and subsequent administration of angiotensin converting enzyme inhibitor (ACEI).

METHODS AND RESULTS

Using the method of hyperinsulin euglycaemic clamp a group of 15 offspring of hypertensive subjects (PHT) were examined who at the time did not differ in basic indicators from a control group of 18 men of similar age. The authors found lower values of glucose consumption (Msubmax), metabolic glucose clearance (MCRsubmax), however statistically significant differences were found in the indexes of insulin sensitivity SI (SI: 46.51% +/- 11.77% vs. 54.28% +/- 7.79%, p < 0.02) and ISI (ISI: 6.6% +/- 3.99% vs. 9.88% +/- 5.05%, p < 0.01). After six weeks of ACEI administration (enalapril 10 mg) the insulin sensitivity in PTH increased significantly in the majority of investigated parameters (MCRsubmax to 9.7 +/- 3.04 mg/kg.min-1, p < 0.05), in indexes of insulin sensitivity (SI to 54.83 +/- 12.9, p < 0.001 and ISI to 9.34 +/- 4.78 mg/kg/min-1, p < 0.01). The insulin sensitivity in PHT who were given ACEI exceeded in some indicators the coresponding values in subgroup of controls which was without medication. After ACEI administration the renin secretion increased and the levels of the plasminogen activator inhibitor (PAI-1) did not change.

CONCLUSIONS

ACEI administration improved the insulin sensitivity in a group of 15 men from families of hypertensive subjects. It exceeded the effect of diet and change of regime which had already influenced the symptoms of metabolic syndrome in a favourable way.