[Circadian variability of arterial blood pressure and the baroreceptor reflex in patients with arterial hypertension of various etiologies].

Circadian variations of blood pressure (BP) in dependence on neurogenous baroreceptor control in patients with essential hypertension (EH) or renovascular hypertension (RH) were studied. Patients with EH demonstrated significantly greater decrease of systolic as well as diastolic BP at night compared to those with RH. Circadian variation rates of systolic and mean BP were also higher in patients with EH. Baroreceptor test exhibited higher cardiochronotropic effect in patients with EH. They had also negative correlation between BP variation rates and BP reaction to baroreceptor test which is absent in patients with RH. The data obtained suggest that neuroregulation mechanisms have less effect on BP level in RH than in EH.