Family history of hypertension and cardiovascular reactivity to forehead cold stimulation in black male children.

The effects of family history of hypertension on cardiovascular reactivity to forehead cold stimulation was examined in 16 black males from 11 to 14 years of age. Measures of blood pressure, heart rate, cardiac output, stroke volume and systemic vascular resistance were obtained during baseline, forehead cold stimulation and recovery phases. Diastolic blood pressure and systemic vascular resistance increases to the forehead cold stimulation were significantly greater in subjects with positive family histories of hypertension than in those with negative family histories. These findings are compared with the results of adult studies and discussed in terms of racial differences in alpha and beta-adrenergically mediated cardiovascular reactivity.