Effect of tobacco smoke on hydrogen sulfide-induced rat thoracic aorta relaxation.
Levels of hydrogen sulfide (H2S), a gaseous signaling molecule, are reduced in the serum of individuals who smoke. We hypothesized that tobacco smoke influenced smooth muscle relaxation by decreasing H2S levels and this effect could also influence expression of cystathionine γ-lyase (CSE) and sulfonylurea receptor-2 (SUR-2). The aim of this study was to explore the effect of tobacco smoke on H2S-mediated rat thoracic aorta relaxation and its possible mechanism. Thirty-two Sprague-Dawley rats were divided into four groups: control (C) group, short-term smoker (SS) group, mid-term smoker (MS) group, and long-term smoker (LS) group. H2S concentrations in serum, action of H2S on rat aortic vascular relaxation, and expression of CSE and SUR-2 in thoracic aortic smooth muscle were measured. Although there was no significant difference in H2S between the C and the SS groups, concentration of H2S was significantly reduced in both the LS and MS groups compared to control (P<0.01). Furthermore, H2S was significantly lower in the LS than in the MS group (P<0.05). Rat aortic vascular relaxation was lower in all three treatment groups compared to the control, with the most significant decrease observed in the LS group (P<0.05 compared to the MS group). Expression of CSE and SUR-2 was reduced in the LS and MS groups compared to control (P<0.05), with the lowest levels observed in the LS group (P<0.05). Therefore, tobacco smoke reduced expression of CSE and SUR-2 in rat thoracic aorta, which may inhibit H2S production and vascular dilation.
Department of Cardiology, Air Force General Hospital of the Chinese People's Liberation Army, Beijing, China.
H T
HT
Zhang
Department of Cardiology, The First People's Hospital of Chuzhou, Chuzhou, China.
T
T
Zhang
Department of Cardiology, Lung and Blood Vessel Disease, Ministry of Education, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Beijing, China.
M
M
Chai
Department of Cardiology, Air Force General Hospital of the Chinese People's Liberation Army, Beijing, China.
J J
JJ
Sun
Department of Cardiology, Air Force General Hospital of the Chinese People's Liberation Army, Beijing, China.
X Y
XY
Yu
Department of Cardiology, Air Force General Hospital of the Chinese People's Liberation Army, Beijing, China.
C Z
CZ
Liu
Department of Cardiology, Air Force General Hospital of the Chinese People's Liberation Army, Beijing, China.
C C
CC
Huang
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects*; D004730:Endothelium, Vascular / Q000187:drug effects*; D006862:Hydrogen Sulfide; D008297:Male; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014028:Tobacco Smoke Pollution
D014028:Tobacco Smoke Pollution; D006862:Hydrogen Sulfide