Change in Fos-like immunoreactivity in the suprachiasmatic nucleus in the adult male rat.
The circadian change in the number of the Fos-like immunoreactive (IR) cells in the suprachiasmatic nucleus (SCN) was examined in the adult male rats, whose eyeballs were enucleated two months before sacrifice. Their circadian rhythms were determined by their locomotor activity. They were sacrificed in the middle of the active phase or inactive phase. Then brain sections were cut for immunocytochemistry for Fos. A marked increase in the number of the Fos-like IR cells was observed in the inactive phase in the SCN, whereas no such increase was observed in the supraoptic nucleus. These results indicate that, in the SCN, Fos expression was changed with endogenous circadian rhythm in the free-running rat.
Koibuchi
N
N
Department of Physiology, Dokkyo University School of Medicine, Tochigi, Japan.
Sakai
M
M
Watanabe
K
K
Yamaoka
S
S
D000818:Animals; D002940:Circadian Rhythm; D015353:Eye Enucleation; D007150:Immunohistochemistry; D008297:Male; D009043:Motor Activity; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains; D013493:Suprachiasmatic Nucleus / Q000166:cytology / Q000502:physiology*
D016760:Proto-Oncogene Proteins c-fos