Premium
Neurotransmitters in the Vestibular Commissural System of the Cat
Author(s) -
FURUYA NOBUHIKO,
YABE TAKAO,
KOIZUMI TATUROU
Publication year - 1992
Publication title -
annals of the new york academy of sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.712
H-Index - 248
eISSN - 1749-6632
pISSN - 0077-8923
DOI - 10.1111/j.1749-6632.1992.tb25238.x
Subject(s) - commissure , vestibular system , neuroscience , anatomy , biology
The present study focused on the transmitters that control the vestibular neural activity and, in particular, that regulate commissural inhibition. Extracellular spikes of a single vestibular neuron were recorded in decerebrate cats. The seven barrels of the electrode, with the exception of the center barrel, were filled with transmitter candidates and their specific antagonists, while the center barrel was filled with 2 M NaCl for extracellular recording. After isolation of a type 1 neuron, chemicals were iontophoretically applied to examine their effects on its activity. The results were as follows: (1) GABA and glycine markedly decreased spontaneous firing of the neurons, while serotonin did not affect their activity. (2) Bicuculline abolished the inhibitory effects of GABA on the neurons. (3) Strychine abolished the effects of glycine. (4) Commissural inhibition induced by electrical stimulation of the contralateral labyrinth was not abolished by strychine but was abolished by bicuculline. We conclude that (1) vestibular type 1 neurons are controlled by GABAergic and glycinergic but not serotoninergic neurons, and (2) commissural inhibition is activated by the GABAA receptor, but not by the GABAB receptor.