The Influence of Perinatal Hypoxia (Asphyxia) on the Distribution of the α1 Subunit of the GABA_A Receptor in the Neocortex of Newborn Rats

The purpose of this work was to study the distribution of the α1 subunit of the GABA_A receptor in the layers of the neocortex of rats in the neonatal period after exposure to hypoxia. The effect of hypoxia on the brain of newborn rats was carried out on the second neonatal day for 1 h at an oxygen content in the respiratory mixture of 7.8%. To identify the α1 subunit of GABA_A receptor, immunohistochemical reaction was used. Protein content was assessed by the density of immunostaining of the reaction product in the cytoplasm and processes of neurons. We studied the somatosensory area of the neocortex at the fifth and tenth neonatal stages (P5, P10). It has been established that, in the early stages of the neonatal period, a significant population of young neurons is present in the neocortex, in the cytoplasm of which the α1 subunit, which is part of the GABA_A receptor, is immunohistochemically detected. By the end of the neonatal period, in control animals, the density of staining of the immunohistochemical product of GABA_A in the layers of the neocortex increases significantly. Exposure to perinatal hypoxia causes a reduction in the number of neurons containing the α1 subunit of the GABA_A receptor and a significant decrease in the density of immunohistochemical staining in all layers of the neocortex.