Gamma-aminobutyric acid-immunoreactive neurons in the rat trigeminal nuclei

Histochemistry. 1993 Jan;99(1):49-55. doi: 10.1007/BF00268020.


The distribution of GABAergic neurons in the rat trigeminal nuclei was studied using a highly specific monoclonal antibody (mAb3A12) to gamma-aminobutyric acid (GABA). Immunopositive cells were relatively abundant in the marginal and gelatinosa beds of the caudal part of the trigeminal spinal tract nucleus, and in the dorsomedial areas of the oral subnucleus and the principal nucleus. A high density of GABA-immunoreactive somata was also found in the rostral part of the oral subnucleus and in the adjacent parvicellular reticular formation as well as in the supratrigeminal and intertrigeminal regions. Thus, the distribution of the GABAergic cells showed a relatively high density in areas related to the convergence of sensory stimuli, and in zones that contain interneurons inhibiting masticatory motoneurons. The results suggest, therefore, that GABA might play an important role both in discriminative sensory processing and in reflex modulation of the orofacial region.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / immunology
  • Biotin
  • Cerebellar Cortex / metabolism
  • Cerebellar Cortex / ultrastructure
  • Glutamate Decarboxylase / immunology
  • Glutamate Decarboxylase / metabolism
  • Immunohistochemistry
  • Motor Neurons / ultrastructure
  • Neurons / immunology
  • Neurons / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Reticular Formation / anatomy & histology
  • Reticular Formation / immunology
  • Reticular Formation / metabolism
  • Spinal Cord / immunology
  • Spinal Cord / metabolism
  • Trigeminal Nuclei / cytology
  • Trigeminal Nuclei / immunology
  • Trigeminal Nuclei / metabolism*
  • gamma-Aminobutyric Acid / immunology
  • gamma-Aminobutyric Acid / metabolism*


  • Antibodies, Monoclonal
  • gamma-Aminobutyric Acid
  • Biotin
  • Glutamate Decarboxylase