Parvalbumin Expression in Rat SubventricularZone as Affected by Acute Hypoxia during Early Postnatal Ontogeny

This study aimed to reveal parvalbumin (PVA) expression in cells of the subventricular zone (SVZ), identify the morphological type of these cells, and estimate the effect of acute hypoxia on the size of this cell population in the Wistar rat neonatal period. PVA-expressing cells were revealed immunohistochemically using Abcam rabbit polyclonal antibodies to this calcium-binding protein. Rats were exposed to hypoxia in a special chamber with 7.8% oxygen in a breathing gas mixture. The brain was examined in the neonatal period on postnatal days 5 and 10. It was found that the SVZ, both in control and experimental rats, contains PVA- expressing cells of the same morphological type, which represent migrating immature neuroblasts (type A). In control animals, throughout the entire neonatal period, the number of these cells remains constant and accounts for more than 20% of the total cell population. Perinatal hypoxic exposure leads to increase the number of PVA-expressing cells, as well as the total number of cells, in the SVZ (to 33%). Thus, perinatal hypoxia activates neurogenesis in the SVZ during the neonatal period. In the same period, some neuroblasts express PVA and may reach a certain degree of differentiation of their neurotransmitter phenotype.