The action of cobra venom on the vestibular compensation and its protective effect after administration of GABA in conditions of unilateral labyrinthectomy

It is known that unilateral labyrinthectomy (UL) causes a syndrome of oculomotor, postural and autonomic
system disorders, which diminish over time in a process of behavioral recovery known as vestibular compensation (VC). The problem
of VC remains one of the actual tasks of modern neuroscience, directly associate with recovery of vestibular nucleus activity on the
injured side. However its central mechanisms are not completely uncovered yet. In the unilaterally labyrinthectomized albino rats the
effect of cobra venom on activity of lateral vestibular neurons and its protective action in combination with GABA was studied.
Materials and methods: Experiments were carried out on six groups of rats: normal, unilaterally labyrinthectomized (UL), UL with
administration of Naja Naja Oxiana (NOX) venom (5% LD50, 21µg/kg, im), normal with combination of GABA (2 mg/kg, im), UL
with combination of GABA and UL with administration of NOX venom and GABA injection. Electrophysiological patterns of lateral
vestibular nucleus neurons at 9th day after the UL in response to stimulation of paraventricular and supraoptic nuclei of hypothalamus
in all groups were studied.
Results: The increasing of inhibitory and excitatory reactions of Deiters’ neurons at early stage of vestibular compensation following
NOX injection and reaching the norm at late stage was revealed. Administration of GABA resulted in depression of activity in normal
and UL groups.
Conclusion: The cobra venom not only causes acceleration of vestibular compensation but also prevents the depressive effects of
GABA on Deiters’ neurons