Effects of K+ Channel Opener WAY120491 on Renal Function in Rabbits.
- Author:
Soo Chang SON
1
;
Jin Fu WEN
;
Dan LI
;
Suhn Hee KIM
;
Kyung Woo CHO
Author Information
1. Department of Physiology, Jeonbug National University Medical School, Chunbuk, Korea. kwcho@moak.chonbuk.ac.kr
- Publication Type:Original Article
- Keywords:
Glibenclamide;
K+ATP channel;
K+ channel opener;
Natriuresis;
Diuresis;
Renal function
- MeSH:
Diuresis;
Extremities;
Glyburide;
Hemodynamics;
Hypertension;
Membranes;
Muscle, Smooth, Vascular;
Natriuresis;
Natriuretic Agents;
Rabbits*;
Water
- From:Korean Journal of Nephrology
2003;22(1):53-62
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: K+ channel opener has been considered as a vasorelaxing agent working through hyperpolarization of vascular smooth muscle cells. Renal tubules-proximal, thick ascending limb of Henle and cortical collecting duct-are the site of the diversity of the K+ channel. ATP-sensitive K+ channel has been observed in the apical membranes of the thick ascending limb of Henle and collecting duct, and basolateral membrane of the proximal tubule. It was also shown that K+ channel opener increased renal hemodynamics and elicited diuretic and natriuretic effects. METHODS: To clarify the renal effects of WAY120491, a K+ channel opener, experiments were performed in unanesthetized normotensive and renal hypertensive rabbits allowing unilateral renal arterial infusion of agent. RESULTS: Intrarenal arterial infusion (0.13, 0.32 and 0.64 microgram/kg/min) of WAY120491 increaased CPAH, CCr, urine volume, UNaV, UKV and CH2O. Renal hemodynamic effects and increments of urine volume and free water clearance were completely blocked by glibenclamide (8.2 g/kg/min), while increments of UNaV and FENa were not significantly affected. Renal hemodynamic and tubular effects of WAY120491 were not significantly different in two-kidney one clip Goldblatt hypertensive rabbits from sham-operated rabbits. CONCLUSIONS: These results suggest that WAY120491 elicits renal effects through ATP-sensitive K+ channel in the renal vasculatures and renal tubules and the renal effects of WAT120491 may not be altered in the hypertension.
