title: Transient developmental expression of monoamine transporters in the rodent forebrain.
abstract: Neurons in first-order sensory thalamic nuclei have been shown to express functional plasma membrane serotonin (SERT) and vesicular monoamine (VMAT2) transporters during early postnatal development. In the present study, we provide an extensive description of the spatial and the temporal patterns of VMAT2 and SERT expression, during early embryonic development and postnatal life, by using in situ hybridization and immunocytochemistry. VMAT2 and SERT genes are transiently expressed in a wide population of non-monoaminergic neurons in the central and peripheral nervous system with a large overlap in the temporal and spatial pattern of expression of both genes. A selective pattern of expression of both genes was observed in the thalamus with expression limited to the dorsal thalamus and more particularly to primary sensory relay nuclei that convey point to point projection maps. Transient expression of the transporters was also observed in sensory cranial nerves, in the hippocampus, cerebral cortex, septum, and amygdala. VMAT2 and SERT gene expression was not necessarily linked, as some neural populations expressed only VMAT2, while others only contained SERT. Since VMAT2 serves to transport catecholamines besides serotonin, we examined the developmental expression of the plasma membrane dopamine and norepinephrine transporters but found no transient expression of these genes. Despite minor temporal disparities, VMAT2 and SERT extinguished almost simultaneously during the second and third weeks of post-natal life. These expressions did not seem to be dependent on peripheral neural inputs, since monocular enucleations and infraorbital nerve cuts effected on the day of birth, did not modify the period of transporter expression or of extinction.
authors.affiliation: INSERM U106, Hôpital de la Salpêtrière, Paris, France.
authors.forename: C
authors.initials: C
authors.lastname: Lebrand
authors.forename: O
authors.initials: O
authors.lastname: Cases
authors.forename: R
authors.initials: R
authors.lastname: Wehrlé
authors.forename: R D
authors.initials: RD
authors.lastname: Blakely
authors.forename: R H
authors.initials: RH
authors.lastname: Edwards
authors.forename: P
authors.initials: P
authors.lastname: Gaspar
mesh_terms: D000818:Animals; D001923:Brain Chemistry / Q000502:physiology; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D050483:Dopamine Plasma Membrane Transport Proteins; D015353:Eye Enucleation; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D008562:Membrane Glycoproteins / Q000235:genetics*; D026901:Membrane Transport Proteins; D051379:Mice; D008809:Mice, Inbred C3H / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D009475:Neurons, Afferent / Q000737:chemistry / Q000502:physiology; D009479:Neuropeptides; D018377:Neurotransmitter Agents / Q000235:genetics*; D050484:Norepinephrine Plasma Membrane Transport Proteins; D016548:Prosencephalon / Q000737:chemistry* / Q000166:cytology / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley / Q000502:physiology*; D012701:Serotonin / Q000235:genetics / Q000378:metabolism; D027981:Symporters; D013788:Thalamus / Q000737:chemistry / Q000166:cytology / Q000502:physiology; D013997:Time Factors; D014276:Trigeminal Nerve / Q000166:cytology / Q000502:physiology; D050492:Vesicular Biogenic Amine Transport Proteins; D050493:Vesicular Monoamine Transport Proteins; D015349:Vision, Monocular / Q000502:physiology
chemical_list: D002352:Carrier Proteins; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D050484:Norepinephrine Plasma Membrane Transport Proteins; D012333:RNA, Messenger; C493453:Slc18a2 protein, mouse; C493454:Slc18a2 protein, rat; C493228:Slc6a2 protein, mouse; C493226:Slc6a2 protein, rat; D027981:Symporters; D050492:Vesicular Biogenic Amine Transport Proteins; D050493:Vesicular Monoamine Transport Proteins; D012701:Serotonin