Estimation of Vasopressin Excretion in the Urine as a Method of Monitoring Vasopressin Secretion During Space Flight

It is demonstrated that, under the circumstances of space flight, the measurement of plasma ADH levels might be misleading and that only the urinary ADH levels provide reliable information. The results of a partially completed survey of ADH levels in urine samples from human subjects in which simultaneous plasma ADH levels were available are included.