Abstract
In neonatal rabbit soleus muscle, different motor units were found to contract with widely varying time courses. Analysis of these data suggest that individual motor units are largely homogeneous for muscle fiber type despite the presence of extensive polyinnervation at birth. We suggest that (1) neonatal motor neurons are effectively differentiated into specific types insofar as they preferentially innervate muscle fibers which give rise to different contraction times, and (2) muscle fibers begin their physiological differentiation into twitch types while still polyinnervated. Possible mechanisms underlying the development of a specific pattern of neuromuscular innervation are discussed.
Original language | English (US) |
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Pages (from-to) | 42-50 |
Number of pages | 9 |
Journal | Developmental biology |
Volume | 111 |
Issue number | 1 |
DOIs | |
State | Published - Sep 1985 |
Externally published | Yes |
ASJC Scopus subject areas
- Molecular Biology
- Developmental Biology
- Cell Biology