Open AccessRho-kinase inhibitor and Nicotinamide Adenine Dinucleotide PHosphate oxidase inhibitor prevent impairment of endothelium-dependent cerebral vasodilation by acute cigarette smoking in rats
Author(s) -
Hiroki Iida,
Mami Iida,
Motoyasu Takenaka,
Naokazu Fukuoka,
Shuji Dohi
Publication year - 2008
Publication title -
jraas. journal of the renin-angiotensin-aldosterone system/journal of the renin-angiotensin-aldosterone system
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.457
H-Index - 46
eISSN - 1752-8976
pISSN - 1470-3203
DOI - 10.3317/jraas.2008.012
Subject(s) - apocynin , nicotinamide adenine dinucleotide phosphate , fasudil , vasodilation , pharmacology , nadph oxidase , medicine , angiotensin ii , anesthesia , chemistry , endocrinology , oxidase test , rho associated protein kinase , biochemistry , kinase , blood pressure , oxidative stress , enzyme
. We previously reported that acute cigarette smoking can cause a dysfunction of endothelium-dependent vasodilation in cerebral vessels, and that blocking the angiotensin II (Ang II) type 1 (AT1) receptor with valsartan prevented this impairment. Our aim was to investigate the effects of a Rho-kinase inhibitor (fasudil) and a Nicotinamide Adenine Dinucleotide PHosphate (NADPH) oxidase inhibitor (apocynin) on smoking-induced endothelial dysfunction in cerebral arterioles. Method. In Sprague—Dawley rats, we used a closed cranial window preparation to measure changes in pial vessel diameters following topical acetylcholine (ACh) before smoking. After one-minute smoking, we again examined the arteriolar responses to ACh. Finally, after intravenous fasudil or apocynin pre-treatment we re-examined the vasodilator responses to topical ACh (before and after cigarette smoking). Results. Under control conditions, cerebral arterioles were dose-dependently dilated by topical ACh (10 -6 M and 10 -5 M). One hour after a one-minute smoking (1 mg-nicotine cigarette), 10 -5 M ACh constricted cerebral arterioles. However, one hour after a one-minute smoking, 10 -5 M ACh dilated cerebral pial arteries both in the fasudil pre-treatment and the apocynin pre-treatment groups, responses that were significantly different from those obtained without fasudil or apocynin pre-treatment. Conclusion. Thus, inhibition of Rho-kinase and NADPH oxidase activities may prevent the above smoking-induced impairment of endothelium-dependent vasodilation.