High-salt diet depresses acetylcholine reactivity proximal to NOS activation in cerebral arteries. Am J Physiol Heart Circ Physiol 2002 Jul;283(1):H353-63
Date
06/14/2002Pubmed ID
12063309DOI
10.1152/ajpheart.00127.2002Scopus ID
2-s2.0-0036299748 (requires institutional sign-in at Scopus site) 43 CitationsAbstract
Rats were fed a low-salt (LS; 0.4% NaCl) or high-salt (HS; 4.0% NaCl) diet for 3 days, and the responses of isolated cerebral arteries to acetylcholine (ACh), the nitric oxide (NO)-dependent dilator bradykinin, and the NO donor 6-(2-hydroxy-1-methyl-2-nitrosohydrazino)-N-methyl-1-hex-anamine (NOC-9) were determined. ACh-induced vasodilation and NO release, assessed with the fluorescent NO indicator 4,5-diaminofluorescein (DAF-2) diacetate, were eliminated with the HS diet. Inhibition of cyclooxygenase, cytochrome P-450 epoxygenase, and acetylcholinesterase did not alter ACh responses. Bradykinin and NOC-9 caused a similar dilation in cerebral arteries of all groups. Arteries from animals on LS or HS diets exhibited similar levels of basal superoxide (O(2)(-)) production, assessed by dihydroethidine fluorescence, and ACh responses were unaffected by O(2)(-) scavengers. Muscarinic type 3 receptor expression was unaffected by dietary salt intake. These results indicate that 1) a HS diet attenuates ACh reactivity in cerebral arteries by inhibiting NO release, 2) this attenuation is not due to production of a cyclooxygenase-derived vasoconstrictor or elevated O(2)(-) levels, and 3) alteration(s) in ACh signaling are located upstream from NO synthase.
Author List
Sylvester FA, Stepp DW, Frisbee JC, Lombard JHMESH terms used to index this publication - Major topics in bold
AcetylcholineAnimals
Bradykinin
Cerebral Arteries
Cholinesterase Inhibitors
Cytochrome P-450 Enzyme Inhibitors
Cytochrome P-450 Enzyme System
Dose-Response Relationship, Drug
Enzyme Inhibitors
Fluorescent Dyes
Free Radical Scavengers
In Vitro Techniques
Male
Nitric Oxide Donors
Nitric Oxide Synthase
Oxygenases
Prostaglandin-Endoperoxide Synthases
Rats
Receptor, Muscarinic M3
Receptors, Muscarinic
Sodium Chloride, Dietary
Superoxides
Triazenes
Vasodilation
Vasodilator Agents
