title: Repeated sauna therapy attenuates ventricular remodeling after myocardial infarction in rats by increasing coronary vascularity of noninfarcted myocardium.
abstract: Repeated sauna therapy (ST) increases endothelial nitric oxide synthase (eNOS) activity and improves cardiac function in heart failure as well as peripheral blood flow in ischemic limbs. The present study investigates whether ST can increase coronary vascularity and thus attenuate cardiac remodeling after myocardial infarction (MI). We induced MI by ligating the left coronary artery of Wistar rats. The rats were placed in a far-infrared dry sauna at 41°C for 15 min and then at 34°C for 20 min once daily for 4 wk. Cardiac hemodynamic, histopathological, and gene analyses were performed. Despite the similar sizes of MI between the ST and non-ST groups (51.4 ± 0.3 vs. 51.1 ± 0.2%), ST reduced left ventricular (LV) end-diastolic (9.7 ± 0.4 vs. 10.7 ± 0.5 mm, P < 0.01) and end-systolic (8.6 ± 0.5 vs. 9.6 ± 0.6 mm, P < 0.01) dimensions and attenuated MI-induced increases in LV end-diastolic pressure. Cross-sectional areas of cardiomyocytes were smaller in ST rats and associated with a significant reduction in myocardial atrial natriuretic peptide mRNA levels. Vascular density was reduced in the noninfarcted myocardium of non-ST rats, and the density of cells positive for CD31 and for α-smooth muscle actin was decreased. These decreases were attenuated in ST rats compared with non-ST rats and associated with increases in myocardial eNOS and vascular endothelial growth factor mRNA levels. In conclusion, ST attenuates cardiac remodeling after MI, at least in part, through improving coronary vascularity in the noninfarcted myocardium. Repeated ST might serve as a novel noninvasive therapy for patients with MI.
authors.affiliation: The Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama, Sugitani, Toyama, Japan.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Sobajima
authors.forename: Takashi
authors.initials: T
authors.lastname: Nozawa
authors.forename: Takuya
authors.initials: T
authors.lastname: Shida
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohori
authors.forename: Takayuki
authors.initials: T
authors.lastname: Suzuki
authors.forename: Akira
authors.initials: A
authors.lastname: Matsuki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Inoue
mesh_terms: D000199:Actins / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000235:genetics; D006332:Cardiomegaly / Q000503:physiopathology / Q000517:prevention & control; D016009:Chi-Square Distribution; D003331:Coronary Vessels / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D004195:Disease Models, Animal; D005786:Gene Expression Regulation; D006439:Hemodynamics; D008297:Male; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D018919:Neovascularization, Physiologic; D052250:Nitric Oxide Synthase Type III / Q000235:genetics; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D029002:Steam Bath; D013997:Time Factors; D014463:Ultrasonography; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics; D016277:Ventricular Function, Left; D017725:Ventricular Pressure; D020257:Ventricular Remodeling
chemical_list: D000199:Actins; D009320:Atrial Natriuretic Factor; D052250:Nitric Oxide Synthase Type III; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; C498862:Acta2 protein, rat; C467498:vascular endothelial growth factor A, rat; C496316:Nos3 protein, rat