title: Altered potassium ATP channel signaling in mesenteric arteries of old high salt-fed rats.
abstract: OBJECTIVE
  Both aging and the consumption of a high salt diet are associated with clear changes in the vascular system that can lead to the development of cardiovascular disease; however the mechanisms are not clearly understood. Therefore, we examined whether aging and the consumption of excess salt alters the function of potassium ATP-dependent channel signaling in mesenteric arteries.
  
  
  METHODS
  Young (7 months) and old (29 months) Fischer 344 x Brown Norway rats were fed a control or a high salt diet (8% NaCl) for 12 days and mesenteric arteries were utilized for vascular reactivity measurements.
  
  
  RESULTS
  Acetylcholine-induced endothelium relaxation was significantly reduced in old arteries (81 ± 4%) when compared with young arteries (92 ± 2%). Pretreatment with the potassium-ATP channel blocker glibenclamide reduced relaxation to acetylcholine in young arteries but did not alter dilation in old arteries. On a high salt diet, endothelium dilation to acetylcholine was significantly reduced in old salt arteries (60 ± 3%) when compared with old control arteries (81 ± 4%). Glibenclamide reduced acetylcholine-induced dilation in young salt arteries but had no effect on old salt arteries. Dilation to cromakalim, a potassium-ATP channel opener, was reduced in old salt arteries when compared with old control arteries.
  
  
  CONCLUSIONS
  These findings demonstrate that aging impairs endothelium-dependent relaxation in mesenteric arteries. Furthermore, a high salt diet alters the function of potassium-ATP-dependent channel signaling in old isolated mesenteric arteries and affects the mediation of relaxation stimuli.
authors: Department of Kinesiology, West Chester University, West Chester USA.
authors: Melissa A
authors: MA
authors: Whidden
authors: Department of Pharmacology, Near East University, Northern Cyprus Turkey.
authors: Bilgen
authors: B
authors: Basgut
authors: Geriatric Research, Education and Clinical Center, Department of Veterans Affairs Medical Center GainesvilleUSA; Department of Pharmacology and Therapeutics, University of Florida, GainesvilleUSA.
authors: Nataliya
authors: N
authors: Kirichenko
authors: Department of Pharmacology, University of Vermont, Burlington USA.
authors: Benedek
authors: B
authors: Erdos
authors: Geriatric Research, Education and Clinical Center, Department of Veterans Affairs Medical Center GainesvilleUSA; Department of Pharmacology and Therapeutics, University of Florida, GainesvilleUSA.
authors: Nihal
authors: N
authors: Tümer
keywords: Age; High salt diet; Potassium channels; Vasodilation