Multiple receptors mediate the trophic effects of serotonin on ventroposterior thalamic neurons in vitro.
Serotonin (5-HT) exerts prominent morphogenetic roles during development. For example, somatosensory cortical barrel formation is altered in mouse models characterized by excessive extracellular 5-HT, suggesting that 5-HT affects development of thalamic afferents and/or neocortical target regions. The present study assessed 5-HT effects in primary cultures of fetal ventroposterior thalamic (VPT) neurons. 5-HT produces concentration-dependent trophic effects, with impressive 59% and 106% peak increases in total neurite length and number of branching points, respectively, at a dose of 30 microM 5-HT. The exposure of VPT neurons to specific 5-HT receptor agonists 8-OH-DPAT (5-HT(1A)), CGS-12066A (5-HT(1B)), DOI (5-HT(2A/2C)), and m-CPBG (5-HT(3)), enhances primary neurite length and number of branching points with rank-order potency 5-HT(1B) > 5-HT(2A/2C) = 5-HT(3) > 5-HT(1A) = vehicle. Trophic 5-HT effects on embryonic VPT neurons are thus much more prominent than previously reported, and can be mediated by multiple 5-HT receptor subtypes.
Persico
Antonio M
AM
Laboratory of Molecular Psychiatry and Neurogenetics, University Campus Bio-Medico, Via Emilio Longoni 83, I-00155 Rome, Italy. a.persico@unicampus.it
Di Pino
Giovanni
G
Levitt
Pat
P
D000704:Analysis of Variance; D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004622:Embryo, Mammalian; D005260:Female; D007150:Immunohistochemistry / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D016501:Neurites / Q000187:drug effects; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011247:Pregnancy; D011985:Receptors, Serotonin / Q000145:classification / Q000502:physiology*; D012701:Serotonin / Q000494:pharmacology*; D018490:Serotonin Agents / Q000494:pharmacology; D013788:Thalamus / Q000166:cytology* / Q000196:embryology
D011985:Receptors, Serotonin; D018490:Serotonin Agents; D012701:Serotonin