Abstract
The neurovascular function was evaluated in 7 hypotensive and 8 normotensive patients on the long-term hemodialysis and compared with the healthy control group. The vascular reactivity to a cold stress was found diminished significantly in these renal failure patients; most severely in the hypotensive group. A role of somatic nerve dysfunction for the diminished vascular reactivity was excluded from the measurements of nerve conduction velocity because the nerve conduction velocity was similar in the two groups. The rise of blood pressure following norepinephrine administration (I.V.) was similar in the two groups. The reactivity was found to be significantly correlated with the level of blood pressure in the uremic patients. (r = 0.52, p <0.05). The response of plasma dopamine-beta-hydroxylase both upon the cold stress and the postural change (450 head-up tilting) was found significantly diminised in the uremic patients. The present study suggests the role of the adrenergic nerve dysfunction in the diminished vascular reactivity and probably in the development of hypotension.
