Coronary arterioles in type 2 diabetic (db/db) mice undergo a distinct pattern of remodeling associated with decreased vessel stiffness
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Paige S. Katz , Aaron J. Trask , Flavia M. Souza-Smith , Kirk R. Hutchinson , Maarten L. Galantowicz , Kevin C. Lord , James A. Stewart Jr. , Mary J
- چاپ و سال / کشور: 2010
Description
Little is known about the impact of type 2 diabetes mellitus (DM) on coronary arteriole remodeling. The aim of this study was to determine the mechanisms that underlie coronary arteriole structural remodeling in type 2 diabetic (db/db) mice. Passive structural properties of septal coronary arterioles isolated from12- to 16-week-old diabetic db/db and control mice were assessed by pressure myography. Coronary arterioles from 12-week-old db/db mice were structurally similar to age-matched controls. By 16 weeks of age, coronary wall thickness was increased in db/db arterioles (p\0.01), while luminal diameter was reduced (control: 118 ± 5 lm; db/db: 102 ± 4 lm, p\0.05), augmenting the wall-to-lumen ratio by 58% (control: 5.9 ± 0.6; db/db: 9.5 ± 0.4, p\0.001). Inward hypertrophic remodeling was accompanied by a 56% decrease in incremental elastic modulus (p\0.05, indicating decreased vessel coronary wall stiffness) and a *30% reduction in coronary flow reserve (CFR) in diabetic mice. Interestingly, aortic pulse wave velocity and femoral artery incremental elastic modulus were increased (p\0.05) in db/db mice, indicating macrovascular stiffness. Molecular tissue analysis revealed increased elastin-to-collagen ratio in diabetic coronaries when compared to control and a decrease in the same ratio in the diabetic aortas. These data show that coronary arterioles isolated from type 2 diabetic mice undergo inward hypertrophic remodeling associated with decreased stiffness and increased elastin-to-collagen ratio which results in a decreased CFR. This study suggests that coronary microvessels undergo a different pattern of remodeling from macrovessels in type 2 DM
Basic Res Cardiol Received: 22 December 2010 / Revised: 9 June 2011 / Accepted: 28 June 2011
