title: Baroregulation of vasopressin release in adipsic diabetes insipidus.
abstract: Adipsic diabetes insipidus (ADI) occurs in association with a heterogeneous group of conditions. We report vasopressin (AVP) responses to hypotension in nine patients with ADI and nine controls. Hypertonic saline infusion produced absent thirst (1.7 +/- 1.7 to 1.5 +/- 1.7 cm, P = 0.99) and AVP responses (0.3 +/- 0.1 to 0.4 +/- 0.1 pmol/liter, P = 0.99) in the ADI group, who also drank less than the control group (258 +/- 200 ml vs. 1544 +/- 306 ml, P < 0.001). Intravenous infusion of trimetaphan camsylate produced a fall in mean arterial pressure of 31.6% +/- 8.9% in patients and 29.4% +/- 6.1% in controls. Plasma AVP concentrations rose from 1.4 +/- 0.8 to 340.3 +/- 497.4 pmol/liter (P < 0.001) in the control group. In three patients with craniopharyngioma, there was no rise in plasma AVP concentrations (0.3 +/- 0.1 to 0.3 +/- 0.1 pmol/liter, P = 0.96), but plasma AVP rose significantly in response to hypotension in the other six patients (0.4 +/- 0.2 to 204.5 +/- 223.2 pmol/liter, P < 0.001). We concluded that the AVP responses to hypotension in ADI are heterogeneous and reflect the site of the lesion causing the diabetes insipidus.
mesh_terms: D000293:Adolescent; D000328:Adult; D000959:Antihypertensive Agents; D001127:Arginine Vasopressin / Q000378:metabolism*; D001794:Blood Pressure / Q000502:physiology*; D003397:Craniopharyngioma / Q000150:complications; D003919:Diabetes Insipidus / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007022:Hypotension / Q000139:chemically induced / Q000503:physiopathology; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D011311:Pressoreceptors / Q000503:physiopathology; D012462:Saline Solution, Hypertonic; D013894:Thirst; D014294:Trimethaphan
chemical_list: D000959:Antihypertensive Agents; D012462:Saline Solution, Hypertonic; D001127:Arginine Vasopressin; D014294:Trimethaphan