Clinical Significance:
Anti-Diuretic Hormone is a hormone released by the neurohypophysis. It has potent anti-diuretic and vasopressor activities. It is released with its carrier protein Neurophysin. Anti-Diuretic Hormone measurement gives a good indicator of posterior pituitary function and activity. Secretion of Anti-Diuretic Hormone is primarily controlled by the osmotic pressure of the plasma. Blood pressure, blood volume, nausea, hypoglycemia, and Angiotensin are other factors regulating Anti-Diuretic Hormone secretion. Urinary Anti-Diuretic Hormone levels are increased by water deprivation and increased by hydration. Urinary Anti-Diuretic Hormone levels are often increased in patients with essential hypertension, Kwashiorkor disease and edema.
Reference Range:
Hydrated: 10 – 50 ng/24 hours
Dehydrated: 100 – 450 ng/24 hours
Procedure:
Anti-Diuretic Hormone is measured by direct EIA/ELISA.
Patient Preparation:
Patient should not be on diuretics, hypertension, or blood pressure medication, if possible, for at least 48 hours prior to collection of specimen.
Specimen Collection:
10 ml of a 24 hour urine collection should be submitted for analysis. No special preservatives are required. Store specimen refrigerated during collection. Specimens should be frozen prior to shipping. Minimum specimen size is 5 ml.
Shipping Instructions:
Ship specimens frozen in dry ice. Provide the total volume per 24 hours.
References:
1. H Gavras. Role of Vasopressin in Clinical Hypertension and Congestive Cardiac Failure: Interaction with the Sympathetic Nervous System. Clinical Chemistry 37: 1828-1830, 1991.
2. SG Srikantia and M Monanram. Antidiuretic Hormone Values in Plasma and Urine of Malnourished Children. Journal of Clinical Endocrinology and Metabolism 31: 312, 1970.