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The Neuromuscular Junction: Measuring Synapse Size, Fragmentation and Changes in Synaptic Protein Density Using Confocal Fluorescence Microscopy
Published on: December 26, 2014
Tenascin is present in human muscle spindles and neuromuscular junctions
F Pedrosa-Domellöf1, I Virtanen, L E Thornell
1Department of Anatomy, Umeå University, Sweden.
Abstract:
We used immunocytochemistry to investigate the presence of tenascin, an extracellular matrix glycoprotein with very restricted tissue distribution, in human skeletal muscle. Tenascin was found in a short segment of the muscle spindle fibres, in the equatorial region where the sensory endings are found, and in the outer layers of the spindle capsule. Tenascin was also found in the neuromuscular junctions of the extrafusal fibres. The close spatial relationship between tenascin and both sensory and motor nerve endings shown here suggests that this glycoprotein is of functional importance in adult nerve-muscle contacts in human skeletal muscle.
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