Somatotopic relations between spinal motoneurones and muscle fibres of the cat's musculus peroneus longus

Brain Res. 1985 May 27;335(1):81-8. doi: 10.1016/0006-8993(85)90278-1.

Abstract

The cat's m.peroneus longus was analyzed with respect to the somatotopic relation between the rostro-caudal site of emergence of ventral root filaments (i.e. rostro-caudal site of motoneurones) and the intramuscular distribution of innervation. Rostro-caudally distinct fractions of ventral roots were stimulated repetitively in order to deplete their respective muscle fibres of glycogen. The intramuscular position of glycogen-depleted fibres was analyzed in transverse sections from different proximo-distal levels. At each level, depleted muscle fibres were dispersed across the whole muscle. No consistent relation was found between the spinal site of origin of a ventral root filament and the proximo-distal distribution of its fibres within the pennate muscle. A significant and evident tendency was found, however, for rostral root filaments (i.e. rostral motoneurones) to innervate a greater number of muscle fibres in anterior than in posterior muscle portions. For caudal root filaments, the opposite pattern of innervation was observed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anterior Horn Cells / cytology*
  • Anterior Horn Cells / physiology
  • Cats
  • Electromyography
  • Glycogen / metabolism
  • Hindlimb
  • Histocytochemistry
  • Motor Neurons / cytology*
  • Muscles / innervation*
  • Muscles / metabolism

Substances

  • Glycogen