Smoking, endothelial function, and Rho-kinase in humans.
OBJECTIVE
Smoking is associated with endothelial dysfunction and activated Rho-kinase in vascular smooth muscle cells (VSMCs) in humans. The purpose of this study was to elucidate the relationship between endothelial function and Rho-kinase activity in forearm VSMCs in healthy young men.


RESULTS
We evaluated the forearm blood flow (FBF) responses to acetylcholine (ACh), fasudil, a Rho-kinase inhibitor, and sodium nitroprusside (SNP) in male smokers (n=10) and nonsmokers (n=14). FBF was measured by using a strain-gauge plethysmography. The vasodilatory effect of ACh was significantly smaller in smokers than that in nonsmokers. The vasodilatory effect of fasudil was significantly greater in smokers than that in nonsmokers. The vasodilatory effects of SNP in the 2 groups were similar. There was a significant correlation between the maximal FBF response to fasudil and that to ACh (r=-0.67; P<0.01). There was no significant correlation between the maximal FBF response to fasudil and that to SNP. The intra-arterial coinfusion of fasudil significantly increased the FBF response to ACh in smokers but not in nonsmokers. There were no significant differences between FBF response to fasudil alone and that in combination with NG-monomethyl-L-arginine in smokers and in nonsmokers. The intra-arterial coinfusion ascorbic acid did not alter the FBF response to fasudil in both groups.


CONCLUSIONS
These findings suggest that smoking is involved in not only endothelial dysfunction but also activation of Rho-kinase in VSMCs in forearm circulation, and that there is a significant correlation between endothelial function and Rho-kinase activity in VSMCs.
Noma
Kensuke
K
Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8551, Japan.
Goto
Chikara
C
Nishioka
Kenji
K
Hara
Keiko
K
Kimura
Masashi
M
Umemura
Takashi
T
Jitsuiki
Daisuke
D
Nakagawa
Keigo
K
Oshima
Tetsuya
T
Chayama
Kazuaki
K
Yoshizumi
Masao
M
Higashi
Yukihito
Y
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000008:administration & dosage / Q000031:analogs & derivatives; D000109:Acetylcholine / Q000008:administration & dosage; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage; D001205:Ascorbic Acid / Q000008:administration & dosage; D004730:Endothelium, Vascular / Q000201:enzymology* / Q000503:physiopathology; D004791:Enzyme Inhibitors / Q000008:administration & dosage; D005542:Forearm / Q000098:blood supply; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D009599:Nitroprusside / Q000008:administration & dosage; D010991:Plethysmography; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D012907:Smoking / Q000009:adverse effects* / Q000378:metabolism*; D014665:Vasodilator Agents / Q000008:administration & dosage; D019323:omega-N-Methylarginine / Q000008:administration & dosage; D054460:rho-Associated Kinases
D000975:Antioxidants; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D047428:Protein Kinase Inhibitors; D014665:Vasodilator Agents; D009599:Nitroprusside; D019323:omega-N-Methylarginine; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D000109:Acetylcholine; D001205:Ascorbic Acid; C049347:fasudil