INSULIN-LIKE GROWTH FACTOR-I AND SODIUM-LITHIUM COUNTERTRANSPORT IN ESSENTIAL-HYPERTENSION AND IN HYPERTENSIVE LEFT-VENTRICULAR HYPERTROPHY

Objective: The aim of this work was to study the insulin-like growth f actor 1 (IGF1), a substance able to promote cell proliferation in vasc ular smooth muscle, in patients with mild-to-moderate hypertension and to analyse its relationship to sodium-lithium countertransport, a gen etic marker of hypertension that is related to cardiovascular complica tions. Method: We studied 32 hypertensive subjects, some with left ven tricular hypertrophy, and 14 healthy subjects. Fasting plasma IGF1 was measured by means of a radioimmunoassay after octadecylsilica chromat ography and Na+-Li+ countertransport was determined by the method of C anessa. Results: Hypertensive patients had higher values of both IGF1 and Na+-Li+ countertransport. We found a positive correlation, irrespe ctive of age, between IGF1 and Na+-Li+ countertransport. The patients with left ventricular hypertrophy had significantly higher plasma IGF1 levels than those without left ventricular hypertrophy. Conclusion: O ur results confirm a possible role for IGF1 in the cardiovascular comp lications of hypertension and emphasize its relationship to geneticall y determined factors.