title: Corticotropin-releasing factor antagonist reduces activation of noradrenalin and serotonin neurons in the locus coeruleus and dorsal raphe in the arousal response accompanied by yawning behavior in rats.
abstract: We previously reported that intracerebroventricular (icv) administration of corticotropin-releasing factor (CRF) antagonist attenuates the arousal response during yawning behavior in rats. However, the CRF-related pathway involved in the arousal response during yawning is still unclear. In the present study, we assessed the involvement of the CRF-containing pathway from the hypothalamic paraventricular nucleus (PVN) to the locus coeruleus (LC) and the dorsal raphe nucleus (DRN) in the arousal response during frequent spontaneous yawning, which was induced by several microinjections of l-glutamate into the PVN in anesthetized rats, using c-Fos immunohistochemistry. The PVN stimulation showed significant increases in activation of PVN CRF neurons, LC noradrenalin (NA) neurons and DRN serotonin (5-HT) neurons as well as arousal response during yawning. But icv administration of a CRF receptor antagonist, α-helical CRF (9-41), significantly inhibited the activation of both LC NA neurons and DRN 5-HT neurons except the activation of CRF neurons in the PVN, and significantly suppressed the arousal response during yawning. These results suggest that the CRF-containing pathway from PVN CRF neurons to LC NA neurons and DRN 5-HT neurons can be involved in the arousal response during yawning behavior.
authors.affiliation: Department of Human Health Science, Tokyo Metropolitan University, Japan.
authors.forename: Natsuko
authors.initials: N
authors.lastname: Kubota
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Amemiya
authors.forename: Chiharu
authors.initials: C
authors.lastname: Motoki
authors.forename: Tomomi
authors.initials: T
authors.lastname: Otsuka
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishijima
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kita
mesh_terms: D059331:Adrenergic Neurons / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001143:Arousal / Q000502:physiology*; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D003346:Corticotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D007150:Immunohistochemistry; D007276:Injections, Intraventricular; D008297:Male; D008845:Microinjections; D009434:Neural Pathways / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D059326:Serotonergic Neurons / Q000187:drug effects / Q000378:metabolism; D015000:Yawning / Q000502:physiology*
chemical_list: D003346:Corticotropin-Releasing Hormone