Table of Contents Author Guidelines Submit a Manuscript
Journal of Diabetes Research
Volume 2016, Article ID 8164518, 13 pages
http://dx.doi.org/10.1155/2016/8164518
Research Article

High Intensity Aerobic Exercise Training Improves Deficits of Cardiovascular Autonomic Function in a Rat Model of Type 1 Diabetes Mellitus with Moderate Hyperglycemia

1Exercise Biochemistry Laboratory, School of Kinesiology, Faculty of Health Sciences, Western University, London, ON, Canada N6A 3K7
2Neurovascular Research Laboratory, School of Kinesiology, Faculty of Health Sciences, Western University, London, ON, Canada N6A 3K7
3Department of Electrical and Computer Engineering, Department of Medical Biophysics and Robarts Research Institute, Western University, London, ON, Canada N6A 3K7
4Department of Physiology and Pharmacology, Western University, London, ON, Canada N6A 3K7
5Lawson Health Research Institute, London, ON, Canada N6C 2R5

Received 8 September 2015; Revised 11 December 2015; Accepted 15 December 2015

Academic Editor: Mark A. Yorek

Copyright © 2016 Kenneth N. Grisé et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Indices of cardiovascular autonomic neuropathy (CAN) in experimental models of Type 1 diabetes mellitus (T1DM) are often contrary to clinical data. Here, we investigated whether a relatable insulin-treated model of T1DM would induce deficits in cardiovascular (CV) autonomic function more reflective of clinical results and if exercise training could prevent those deficits. Sixty-four rats were divided into four groups: sedentary control (C), sedentary T1DM (D), control exercise (CX), or T1DM exercise (DX). Diabetes was induced via multiple low-dose injections of streptozotocin and blood glucose was maintained at moderate hyperglycemia (9–17 mM) through insulin supplementation. Exercise training consisted of daily treadmill running for 10 weeks. Compared to C, D had blunted baroreflex sensitivity, increased vascular sympathetic tone, increased serum neuropeptide Y (NPY), and decreased intrinsic heart rate. In contrast, DX differed from D in all measures of CAN (except NPY), including heart rate variability. These findings demonstrate that this T1DM model elicits deficits and exercise-mediated improvements to CV autonomic function which are reflective of clinical T1DM.