A novel protocol for assessing exercise performance and dystropathophysiology in the mdx mouse. Issue 4 (5th August 2014)

• Record Type: Journal Article
• Authors: Rocco, Andrew B.; Levalley, Jewel C.; Eldridge, Jennifer A.; Marsh, Susan A.; Rodgers, Buel D.
• Is Part Of: Muscle & nerve. Volume 50:Issue 4(2014:Oct.)
• Page Start: 541
• Page End: 548
• Publication Date: 2014-08-05
• Subjects: Neuromuscular diseases -- Periodicals; Muscles -- Periodicals; Nerves -- Periodicals; 616.74
• DOI: 10.1002/mus.24184
• Languages: English
• ISSNs: 0148-639X

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p> <italic>Introduction</italic>: Dystrophinopathy in the young <italic>mdx</italic> mouse model of Duchenne muscular dystrophy is comparatively mild, requires induction, and is rarely assessed with tests of systemic muscle function in whole animals. <italic>Methods</italic>: A modified TREAT‐NMD induction protocol was used to evaluate respiratory and exercise performance, starting and ending with maximum oxygen consumption (V<sc>O</sc>_2max) tests. <italic>Results</italic>: The initial and/or final V<sc>O</sc>_2max, time to exhaustion, speed at exhaustion, and total expended calories were significantly lower in <italic>mdx</italic> mice. Episodic V<sc>O</sc>₂ and V<sc>CO</sc>₂ fluctuations occurred during training and resulted in dissociated patterns of V<sc>O</sc>₂ and respiratory exchange ratio (RER). These fluctuations further resulted in significantly greater V<sc>O</sc>₂ coefficient of variation and RER values and lower minimal V<sc>O</sc>₂ values. <italic>Conclusions</italic>: Quantifying respiratory performance during exercise is a potentially useful means for studying pathophysiology in <italic>mdx</italic> mice, as it assesses intact animals over time, is more sensitive than some histological markers, and assesses systemic muscle function. <italic>Muscle Nerve</italic> 50: 541–548, 2014</p> </abstract>