Fos expression in the brainstem nuclei evoked by nasal air-jet stimulation in rats.
BACKGROUND
Noxious stimulation of the nasal mucosa may induce protective reflexes in the upper airway in rats. Previously, we have reported that nasal air-jet stimulation increases the activities of the laryngeal muscles in decerebrate cats; however, the neuronal mechanism of this phenomenon still is not clarified.


METHODS
After the application of nasal air-jet stimulation for 2 hours, we investigated the distribution of Fos-positive cells (FPCs) throughout the medulla compared with sham-operated rats using Fos immunoreactivity.


RESULTS
FPCs in the spinal trigeminal nucleus, the parvocellular reticular nucleus, and the nucleus of the solitary tract were more frequent than the sham-operated rats.


CONCLUSIONS
These results suggest that the afferents induced by air-jet stimulation were conveyed to these FPCs and that some of these cells might participate in the augmentation of laryngeal muscle activities during nasal air-jet stimulation.
Kunibe
Isamu
I
Department of Otolaryngology-Head and Neck Surgery, Asahikawa Medical College, Asahikawa, Japan. kunibe@asahikawa-med-u.sl
Nonaka
Satoshi
S
Katada
Akihiro
A
Adachi
Masaaki
M
Arakawa
Takuya
T
Harabuchi
Yasuaki
Y
D000388:Air; D000818:Animals; D005260:Female; D015870:Gene Expression; D016762:Genes, fos / Q000502:physiology*; D008297:Male; D009296:Nasal Cavity / Q000294:innervation*; D010812:Physical Stimulation / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D017552:Solitary Nucleus / Q000378:metabolism* / Q000648:ultrastructure