Regulation of dendrite formation of Purkinje cells by serotonin through serotonin(1A) and serotonin(2A) receptors in culture.

摘要

Serotonergic fibers and receptors appear in the rat cerebellum during early postnatal development. In the present study, we investigated the actions of serotonin (5-HT) and its receptors in the dendrite formation of Purkinje cells in organotypic cultures of anterior and posterior lobes of the cerebellum at postnatal day 7. In anterior lobes after 4 days in vitro (4DIV), the dendritic areas and branchings of Purkinje cells were increased by the treatment of 2microM 5-HT, but decreased by 20microM 5-HT. In posterior lobes after 4DIV, the dendritic areas of Purkinje cells were increased by 5-HT (2, 20 and 200microM). In contrast, 5-HT treatment decreased dendritic areas of Purkinje cells in both anterior and posterior lobes after 7DIV. Next, we determined the actions of specific 5-HT receptors in mediating the effects of 5-HT by treatment with selective 5-HT receptor agonists. In anterior lobes after 4DIV, dendritic areas of Purkinje cells were increased by a 5-HT(1A) receptor agonist (8-OH-DPAT), whereasdecreased by a 5-HT(2A) receptor agonist (DOI). The present study suggested that the dendrite formation of Purkinje cells is promoted by 5-HT through 5-HT(1A) receptors, but inhibited by 5-HT through 5-HT(2A) receptors.