Intergeniculate leaflets lesion delays but does not prevent the integration of photoperiodic change by the suprachiasmatic nuclei.
The duration of the photosensitive phase of the suprachiasmatic nuclei (SCN), as revealed by light-induced Fos protein expression, depends on the photoperiod and is tied to the length of the night. We show here in Syrian hamsters that after a transfer from long to short photoperiod, lengthening of the photosensitive phase of the SCN is significantly delayed but not abolished when the intergeniculate leaflets (IGL) are lesioned. Thus IGL modulate the integration by the SCN of a photoperiodic change.
Menet
J
J
CNRS-UMR 7518, Neurobiologie des Fonctions Rythmiques et Saisonnières, Université Louis Pasteur, 12 rue de l'Université, 67000 Strasbourg, France.
Vuillez
P
P
Jacob
N
N
Pévet
P
P
D000818:Animals; D019771:Axotomy; D002452:Cell Count; D002940:Circadian Rhythm / Q000502:physiology*; D006224:Cricetinae; D015536:Down-Regulation / Q000502:physiology; D005829:Geniculate Bodies / Q000166:cytology / Q000502:physiology* / Q000601:surgery; D007150:Immunohistochemistry; D008297:Male; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism; D009929:Organ Size; D010775:Photic Stimulation; D017440:Photoperiod; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D012621:Seasons; D013493:Suprachiasmatic Nucleus / Q000166:cytology / Q000502:physiology*; D013737:Testis / Q000378:metabolism; D014795:Visual Pathways / Q000166:cytology / Q000502:physiology*
D009478:Neuropeptide Y; D016760:Proto-Oncogene Proteins c-fos