ANTIDIURETIC HORMONE ACTIVITY IN SHEEP AFTER FEEDING

• Published in: Experimental physiology Vol. 50; no. 1; pp. 65 - 78
• Main Authors: Stacy, B. D., Brook, A. H.
• Format: Journal Article
• Language: English
• Published: England The Physiological Society 01.01.1965
• Subjects: Animals; Arginine Vasopressin; Body Fluids; Diuresis; Fluids and Secretions; Natriuresis; Nutritional Physiological Phenomena; Nutritional Sciences; Physiology; Potassium; Sheep; Urine; Vasopressins; Water-Electrolyte Balance; WATER-ELECTROLYTE BALANCE; NATRIURESIS; PHYSIOLOGY; EXPERIMENTAL LAB STUDY; URINE; SHEEP; VASOPRESSIN; NUTRITION; POTASSIUM; DIURESIS; EXCRETION
• ISSN: 0958-0670; 0033-5541; 1469-445X
• DOI: 10.1113/expphysiol.1965.sp001771

Pen-fed sheep increased the concentration of their urine after receiving their daily ration, and evidence is presented to indicate that the change was brought about by the action of antidiuretic hormone (ADH). Post-prandial urine, but not urine from unfed animals, caused inhibition of urine flow when injected into water-loaded sheep. The antidiuretic material in post-prandial urine was assumed to be ADH because (a) it could be extracted by a specific procedure, (b) it was similar to synthetic arginine vasopressin in its action on water and electrolyte excretion in water-loaded sheep, and (c) its biological activity was destroyed by thioglycollate or by trypsin. It was also found that there was an increase in plasma osmotic pressure after feeding, so that conditions favoured the release of ADH. It is therefore concluded that normal, pen-fed sheep regularly experience conditions that classically stimulate the neurohypophysis to control the renal excretion of water by secreting ADH. The action of ADH on electrolytes is discussed, and it is concluded that the sheep, like other animals, does not depend upon the hormone to regulate the renal excretion of Na and K.