title: Chemosensitive serotonergic neurons are closely associated with large medullary arteries.
abstract: We have previously shown that serotonergic neurons of the medulla are strongly stimulated by an increase in CO(2), suggesting that they are central respiratory chemoreceptors. Here we used confocal imaging and electron microscopy to show that neurons immunoreactive for tryptophan hydroxylase (TpOH) are tightly apposed to large arteries in the rat medulla. We used patch-clamp recordings from brain slices to confirm that neurons with this anatomical specialization are chemosensitive. Serotonergic neurons are ideally situated for sensing arterial blood CO(2), and may help maintain pH homeostasis via wide-ranging effects on brain function. The results reported here support a recent proposal that sudden infant death syndrome (SIDS) results from a developmental abnormality of medullary serotonergic neurons.
authors.affiliation: Department of Neurology, Yale University, 333 Cedar Street, New Haven, Connecticut 06510, USA.
authors.forename: S R
authors.initials: SR
authors.lastname: Bradley
authors.forename: V A
authors.initials: VA
authors.lastname: Pieribone
authors.forename: W
authors.initials: W
authors.lastname: Wang
authors.forename: C A
authors.initials: CA
authors.lastname: Severson
authors.forename: R A
authors.initials: RA
authors.lastname: Jacobs
authors.forename: G B
authors.initials: GB
authors.lastname: Richerson
mesh_terms: D000818:Animals; D001158:Arteries / Q000294:innervation* / Q000648:ultrastructure; D002628:Chemoreceptor Cells / Q000166:cytology / Q000378:metabolism*; D008526:Medulla Oblongata / Q000098:blood supply* / Q000166:cytology / Q000502:physiology; D009474:Neurons / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D051381:Rats; D012701:Serotonin / Q000378:metabolism*; D014365:Tryptophan Hydroxylase / Q000096:biosynthesis
chemical_list: D012701:Serotonin; D014365:Tryptophan Hydroxylase