VOLUME REGULATION IN MAN DURING NECK-OUT IMMERSION IN A MEDIUM WITH HIGH SPECIFIC-GRAVITY (DEAD SEA-WATER)

  • 1 January 1984
    • journal article
    • research article
    • Vol. 20  (2) , 109-112
Abstract
Effect of immersion for 4 h on arterial blood pressure and the rate of urinary sodium excretion was studied in 5 subjects both in fresh water and in Dead Sea water (specific gravity 1.19) at 34.degree. C. Following 100 min of immersion, mean systolic and diastolic blood pressure decreased (P < 0.01) in subjects immersed in fresh water, and increased (P < 0.05) in those immersed in Dead Sea water. While immersion in fresh water led to hypotension, it was associated with an increased natriuresis. The hypertensive response to immersion in Dead Sea water was not associated with an increased natriuresis. Under the unique conditions of this experiment, urinary excretion of Na becomes independent of systemic arterial blood pressure and is presumably governed by neurohumoral influences originating in the baroreceptors of the low pressure system.