Extracellular nitric oxide signaling in the hamster biological clock.
Nocturnal light pulses induce phase shifts in circadian rhythms and activate cFos expression in the suprachiasmatic nuclei (SCN). We have studied the role of nitric oxide (NO) in the intercellular communication within the dorsal and ventral portions of the SCN in Syrian hamsters. Administration of the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide blocked photic phase advances in a dose-dependent manner and inhibited light-induced cFos-ir, without affecting light-induced circadian phase delays. These results suggest that NO may act as an intercellular messenger in the SCN, mediating light-induced phase advances.
Plano
Santiago A
SA
Laboratorio de Cronobiología, Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Roque Saenz Peña 352, Bernal B1876BXD, Buenos Aires, Argentina.
Agostino
Patricia V
PV
Golombek
Diego A
DA
D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D006224:Cricetinae; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D015398:Signal Transduction
D016760:Proto-Oncogene Proteins c-fos; D009569:Nitric Oxide