Role of vasopressin in 24-hour blood pressure regulation in diabetic patients with autonomic neuropathy
Data
2002-01-01
Tipo
Artigo
Título da Revista
ISSN da Revista
Título de Volume
Resumo
To evaluate the role of vasopressin (AVP) on blood pressure (BP) in diabetic patients with autonomic neuropathy (AN), 10 patients were studied on a fixed sodium and potassium diet. On days 4 and 7, a 24-h BP monitoring, as well as blood and urine samples for sodium, potassium, creatinine, and osmolality determinations were obtained for every 4-h period either placebo or an AVP-V-1-antagonist (d(CH2)(5)Tyr(me)AVP; 0.5 mg; AVP(i)) were given iv at 1 PM. On placebo, systolic BP (SBP) showed a progressive elevation during the day, declining after 12 Pm (8 AM to 12 AM 122 +/- 9; 12 AM to 4 PM 125 +/- 11; 4 PM to 8 PM 134 +/- 14; 8 PM to 12 PM 136 +/- 14, 12 PM to 8 AM 131 +/- 17 mm Hg). On AVP(i) this rise in SBP was blunted: 8 AM to 12 AM 125 +/- 122; 12 AM to 4 PM 121 +/- 21; 4 PM to 8 PM 126 +/- 16; 8 PM to 12 PM 129 +/- 14; 12 PM to 8 AM 124 12 mm Hg. Creatinine clearance and diureses were greater during the night, both with placebo and AVP(i). Plasma osmolality did not change on either day, although serum sodium decreased after AVP(i), reaching the lowest values at 4 PM to 8 PM period (137 +/- 4.7 v 131 +/- 3.8 mEq/L; P < .05). With placebo, fractional excretion of sodium (FENa increased from 0.43% +/- 0.32% during 12 h of orthostasis to 0,92% +/- 1.05% during 12 h of recumbency (P < .02). With AVP(i), the FENa on orthostasis did not differ from that with placebo, although BP values were lower and did not increase with recumbency (0.58 +/- 0.57 v 0.73% +/- 0.49%; NS). in conclusion, our results show that in diabetic patients with AN, vasopressin participates in BP control by stimulating vascular and renal V-1 receptors, which results in vasoconstriction and sodium reabsorption. (C) 2002 American Journal of Hypertension, Ltd.
Descrição
Citação
American Journal of Hypertension. New York: Elsevier B.V., v. 15, n. 1, p. 42-47, 2002.