Vasoactive hormones in uraemic patients with chronic hypotension.

as catecholamines, plasma renin activity (PRA), angioResults. The mean time on haemodialysis ( HD) was tensin II (AII ), atrial natriuretic peptide ( ANP), or longer in hypotensive patients than in normotensive arginine vasopressin ( AVP) are often elevated in patients (P<0.01). Catecholamine levels were higher uraemic patients on maintenance HD [4,7,9 ]. Plasma in the whole group of HD patients than in controls catecholamine levels are even more elevated in hypo(P<0.01). Catecholamine levels were higher in hypo- tensive HD patients, while the pressor response to tensive patients than in normotensive patients, but the noradrenaline infusion has been found to be markedly differences reached significance only for adrenaline blunted in these patients [6 ]. An increased PRA and (P<0.05). PRA and plasma AII levels were higher in AII levels and a reduced pressor response to AII have hypotensive patients than in the other two groups been reported in hypotensive HD patients [7], sug(P<0.05), while no differences were observed between gesting a vascular resistance to vasoconstrictor stimuli normotensive patients and controls. Plasma ANP and in this situation. Plasma ANP levels are increased in AVP levels were higher in HD patients than in controls uraemic patients, but ANP levels are mainly related to (P<0.01), but there were no differences between hypo- changes in fluid volume rather than to blood pressure tensive and normotensive patients. In HD patients, [9]. AVP might influence blood pressure in uraemic mean blood pressure inversely correlated with PRA patients through its vasoconstrictor effect mediated (r=’0.59, P<0.01) and plasma AII levels (r=’0.80, through the activation of the vascular V 1 receptors P<0.01). [10]. Conclusions. Our results indicate that in HD patients To evaluate the possible role of an imbalance of the with chronic hypotension there is an activation of the main vasoregulatory systems on chronic hypotension sympathetic and the renin‐angiotensin systems. This in HD patients, we measured plasma levels of catecholactivation is probably secondary in an attempt to amines, PRA, AII, ANP, AVP, and parathormone compensate the vascular resistance to pressor stimuli (PTH ) in a group of HD patients with chronic hyporeported in these patients.