SEROTONIN RECEPTOR BLOCKADE IMPAIRS NEUROBLAST MIGRATION IN THE ROSTRAL MIGRATORY STREAM OF THE ADULT RAT

In the adult brain, neuroblasts originating in the subventricular zone of the lateral ventricles migrate along the rostral migratory stream (RMS) to the olfactory bulb, where they differentiate and integrate. It has been found that neuroblasts in the RMS express the serotonin receptor subtype 5-HT3. The aim of our study was to examine the role of serotonin receptor 5-HT3 in neuroblasts migration within the RMS. To this aim, we used the selective 5-HT3 receptor antagonist, Granisetron, and examined neuroblast migration in vitro. Following intraperitoneal administration of a single dose of Granisetron (1 mg/kg body weight), adult rats survived for 1 hour. The RMS was then dissected from coronal brain sections. RMS explants were cultured in Neurobasal medium with additives for 72 hours. Neuroblast migration was assessed using images obtained with an inverted microscope. Migration parameters, such as longest migration length, area of neuroblast migration and extent of the migration chain outgrowth were measured. We found that the average length of the longest migration and the area of neuroblast migration were significantly reduced in rats administered with granisetron compared with control animals. Differences in the number and extent of migration chains growing from the explants were observed between RMS explants from control animals and explants from animals after granisetron administration. Our results suggest that blockade of the 5-HT3 serotonin receptor negatively regulates neuroblast migration in RMS.
Supported by APVV-23-0274, VEGA grant 2/0107/26