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Maturation of the neuromuscular junction in masseters of human fetus

W Molina1, E Reyes, N Joshi

  • 1Department of Physiology, Faculty of Medicine, Universidad de Los Andes, Mérida, Venezuela. wjmw55@hotmail.com

Romanian Journal of Morphology and Embryology = Revue Roumaine De Morphologie Et Embryologie
|September 3, 2010
PubMed

Insights

Histological maturation of the neuromuscular junction in human fetal masseter muscles begins by 12 weeks of gestation. This study observed early signs of neuromuscular development, including axon presence and receptor clustering.

Area of Science:

  • Developmental biology
  • Neuroscience
  • Histology

Background:

  • The neuromuscular junction (NMJ) is crucial for muscle function.
  • Understanding NMJ development in human fetuses provides insights into early motor system formation.

Purpose of the Study:

  • To determine if histological maturation of the fetal masseter NMJ commences by 12 weeks of gestation.
  • To investigate early developmental markers of the NMJ in human fetuses.

Main Methods:

  • Masseter muscles from 14 human fetuses (12 weeks gestation) were analyzed.
  • Histological examination using Bielschowsky and Holzer stains for neurofibrils and glial cells.
  • Immunohistochemistry with alpha-bungarotoxin for nicotinic receptors and anti-GAD for neuronal terminals.

Main Results:

  • Each neuromuscular junction exhibited one axon.
  • Glial cells were observed surrounding branched axons.
  • Nicotinic receptors were clustered at the NMJ, with neuronal terminals and large oval nuclei present.

Conclusions:

  • The findings indicate that NMJ maturation in human fetal masseter muscles is initiated by 12 weeks of gestation.
  • Early histological evidence supports the commencement of NMJ development at this gestational stage.
Abstract

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