Extracellular nitric oxide signaling in the hamster biological clock

PLANO SA; AGOSTINO PV; GOLOMBEK DA

FEBS LETTERS

ELSEVIER SCIENCE BV

Año: 2007 vol. 581 p. 5500 - 5504

0014-5793

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.