Blood Pressure Response to a Calcium Entry Blocker in Normotensive Subjects With or Without a Family History of Hypertension

Abstract

The possibility that a familial background of hypertension might influence the blood pressure response to a calcium entry blocker was evaluated in 15 normotensive relatives of patients with essential hypertension and 18 normoten sive subjects with no family history of hypertension. Under control conditions, blood pressure, heart rate, plasma noradrenaline, adrenaline, and renin activ ity did not differ between the two groups. Nifedipine, at a dose of 10 mg admin istered sublingually, lowered the blood pressure and increased the heart rate, plasma noradrenaline, and renin activity. The normotensive relatives of patients with essential hypertension did not differ in their responses from the normoten sive subjects with no family history of hypertension, with the exception of plasma noradrenaline thirty minutes after nifedipine. These results provide evi dence to suggest that there is no functional abnormality with increased depen dency of vascular smooth muscle tone on calcium influx in the prehypertensive state.