抄録
In mammals, circadian rhythms are driven by a pacemaker located in the suprachiasmatic nuclei (SCN) of the hypothalamus. The pacemaker composed of an ensemble of multiple, single-cell oscillators in the SCN. We have reported circadian oscillation of arginine vasopressin (AVP) release in dispersed SCN cell culture. The organotypic SCN slice culture also showed circadian oscillation of AVP release. The period length of the slice containing whole SCN was almost same as that of behavioral rhythm observed in vivo (23.78 +/- 0.04h, mean +/- SEM). When the ventral part was removed by surgical cut across the slice in the horizontal plane, however, it became shorter (23.19 +/- 0.10h). On the other hand, the removal of the dorsal part did not affect the period length. These results suggest that the oscillators in ventral and dorsal cells have difference in period length and that the dorsal oscillators are regulated by ventral one to form a single integrated oscillator. [Jpn J Physiol 54 Suppl:S209 (2004)]
