Structure-activity relationships in rodent diaphragm muscle fibers vs. neuromuscular junctions |
| |
Authors: | Sieck Dylan C Zhan Wen-Zhi Fang Yun-Hua Ermilov Leonid G Sieck Gary C Mantilla Carlos B |
| |
Institution: | a Department of Anesthesiology, College of Medicine, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA b Department of Physiology & Biomedical Engineering, College of Medicine, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA |
| |
Abstract: | The diaphragm muscle (DIAm) is a highly active muscle of mixed fiber type composition. We hypothesized that consistent with greater activation history and proportion of fatigue-resistant fibers, neuromuscular transmission failure is lower in the mouse compared to the rat DIAm, and that neuromuscular junction (NMJ) morphology will match their different functional demands. Minute ventilation and duty cycle were higher in the mouse than in the rat. The proportion of fatigue-resistant fibers was similar in the rat and mouse; however the contribution of fatigue-resistant fibers to total DIAm mass was higher in the mouse. Neuromuscular transmission failure was less in mice than in rats. Motor end-plate area differed across fibers in rat but not in mouse DIAm, where NMJs displayed greater complexity overall. Thus, differences across species in activation history and susceptibility to neuromuscular transmission failure are reflected in the relative contribution of fatigue resistant muscle fibers to total DIAm mass, but not in type-dependent morphological differences at the NMJ. |
| |
Keywords: | Motor unit Plethysmography Morphometry Respiratory muscles Fiber type |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|