FORMATION OF THE GABAERGIC NEURAL NETWORK IN VENTROLATERAL PARTS OF THE OF SOLITARY TRACT NUCLEUS IN NORM AND AFTER PRENATAL SEROTONIN DEFICIENCY

Dynamics of formation of inhibitory GABAergic network in ventral and lateral subnuclei of a solitary tract nucleus (STN) in the early postnatal period was studied under normal conditions and with prenatal deficiency of serotonin. To detect GABAergic neurons, immunocytochemical method was applied, with the use of rabbit polyclonal antibodies against GAD-67. It was found that in the first postnatal week, ventral and lateral STN subnuclei demonstrated high GABA expression as suggested by a significant number of GAD-67-immunopositive neurons; their number in the ventral subnucleus was almost 1,3 times higher than in the lateral one. During the second and third weeks, GABA expression decreased and, simultaneously, the density of terminals and synaptic structures containing GABA in neuropil of both subnuclei increased. It was shown that prenatal deficiency of serotonin in ventral and lateral STN subnuclei resulted in sharp decrease of GABA expression in the early postnatal period. By the end of the third week, a loose network of GABAergic terminals remained in the neuropil, and the density of synaptic structures increased.

solitary tract nucleus, respiratory nuclei, GABA, serotonin, early postnatal period