Effects of hydration in rats and mice with polycystic kidney disease.

Abstract

Vasopressin and V2 receptor signaling promote polycystic kidney disease (PKD) progression, raising the question whether suppression of vasopressin release through enhanced hydration can delay disease advancement. Enhanced hydration by adding 5% glucose to the drinking water has proven protective in a rat model orthologous to autosomal recessive PKD. We wanted to exclude a glucose effect and explore the influence of enhanced hydration in a mouse model orthologous to autosomal dominant PKD. PCK rats were assigned to normal water intake (NWI) or high water intake (HWI) groups achieved by feeding a hydrated agar diet (HWI-agar) or by adding 5% glucose to the drinking water (HWI-glucose), with the latter group used to recapitulate previously published results. Homozygous Pkd1 R3277C (Pkd1(RC/RC)) mice were assigned to NWI and HWI-agar groups. To evaluate the effectiveness of HWI, kidney weight and histomorphometry were assessed, and urine vasopressin, renal cAMP levels, and phosphodiesterase activities were measured. HWI-agar, like HWI-glucose, reduced urine vasopressin, renal cAMP levels, and PKD severity in PCK rats but not in Pkd1(RC/RC) mice. Compared with rat kidneys, mouse kidneys had higher phosphodiesterase activity and lower cAMP levels and were less sensitive to the cystogenic effect of 1-deamino-8-d-arginine vasopressin, as previously shown for Pkd1(RC/RC) mice and confirmed here in Pkd2(WS25/-) mice. We conclude that the effect of enhanced hydration in rat and mouse models of PKD differs. More powerful suppression of V2 receptor-mediated signaling than achievable by enhanced hydration alone may be necessary to affect the development of PKD in mouse models.

• Authors: Katharina Hopp, Xiaofang Wang, Hong Ye, María V Irazabal, Peter C Harris, Vicente E Torres
• Journal: American journal of physiology. Renal physiology (Am J Physiol Renal Physiol) Vol. 308 Issue 3 Pg. F261-6 (Feb 01 2015) ISSN: 1522-1466 [Electronic] United States
• PMID: 25503729 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 the American Physiological Society.

Chemical References

• Receptors, Vasopressin
• Arginine Vasopressin

Topics

• Animals
• Arginine Vasopressin (metabolism)
• Disease Models, Animal
• Drinking (physiology)
• Hypodermoclysis (adverse effects)
• Kidney (metabolism, pathology)
• Mice, Inbred C57BL
• Mice, Transgenic
• Polycystic Kidney Diseases (metabolism)
• Rats
• Receptors, Vasopressin (metabolism)