Structure-activity relationships in rodent diaphragm muscle fibers vs. neuromuscular junctions

Dylan C. Sieck, Wen Zhi Zhan, Yun Hua Fang, Leonid G. Ermilov, Gary C. Sieck, Carlos B. Mantilla

Research output: Contribution to journalArticlepeer-review

53 Scopus citations


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.

Original languageEnglish (US)
Pages (from-to)88-96
Number of pages9
JournalRespiratory Physiology and Neurobiology
Issue number1
StatePublished - Jan 15 2012


  • Fiber type
  • Morphometry
  • Motor unit
  • Plethysmography
  • Respiratory muscles

ASJC Scopus subject areas

  • General Neuroscience
  • Physiology
  • Pulmonary and Respiratory Medicine


Dive into the research topics of 'Structure-activity relationships in rodent diaphragm muscle fibers vs. neuromuscular junctions'. Together they form a unique fingerprint.

Cite this