title: Electrophysiological Assessment of Serotonin and GABA Neuron Function in the Dorsal Raphe during the Third Trimester Equivalent Developmental Period in Mice.
abstract: Alterations in the development of the serotonin system can have prolonged effects, including depression and anxiety disorders later in life. Serotonin axonal projections from the dorsal raphe undergo extensive refinement during the first 2 weeks of postnatal life in rodents (equivalent to the third trimester of human pregnancy). However, little is known about the functional properties of serotonin and GABA neurons in the dorsal raphe during this critical developmental period. We assessed the functional properties and synaptic connectivity of putative serotoninergic neurons and GABAergic neurons in the dorsal raphe during early [postnatal day (P) P5-P7] and late (P15-P17) stages of the third trimester equivalent period using electrophysiology. Our studies demonstrate that GABAergic neurons are hyperexcitable at P5-P7 relative to P15-P17. Furthermore, putative serotonin neurons exhibit an increase in both excitatory and GABAA receptor-mediated spontaneous postsynaptic currents during this developmental period. Our data suggest that GABAergic neurons and putative serotonin neurons undergo significant electrophysiological changes during neonatal development.
authors.affiliation: Department of Neurosciences, University of New Mexico Health Sciences Center , Albuquerque, New Mexico 87131.
authors.forename: Russell A
authors.initials: RA
authors.lastname: Morton
authors.affiliation: Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine , Maebashi 371-8511, Japan.
authors.forename: Yuchio
authors.initials: Y
authors.lastname: Yanagawa
authors.affiliation: Department of Neurosciences, University of New Mexico Health Sciences Center , Albuquerque, New Mexico 87131.
authors.forename: C Fernando
authors.initials: CF
authors.lastname: Valenzuela
mesh_terms: D000818:Animals; D065847:Dorsal Raphe Nucleus / Q000502:physiology*; D055724:Electrophysiological Phenomena / Q000502:physiology; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D005260:Female; D059330:GABAergic Neurons / Q000502:physiology*; D008297:Male; D008810:Mice, Inbred C57BL; D011247:Pregnancy; D011263:Pregnancy Trimester, Third / Q000502:physiology*; D011963:Receptors, GABA-A / Q000378:metabolism*; D059326:Serotonergic Neurons / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D011963:Receptors, GABA-A; D012701:Serotonin
keywords: Monoamine; electrophysiology; neonatal