Accession Number : ADA325695

Title :   Cellular Analysis of Circadian Rhythmicity in Cultured SCN Neurons.

Descriptive Note : Final rept. 1 Jul 93-30 Nov 96,

Corporate Author : MASSACHUSETTS GENERAL HOSPITAL BOSTON

Personal Author(s) : Reppert, Steven M.

PDF Url : ADA325695

Report Date : 31 JAN 1997

Pagination or Media Count : 3

Abstract : In mammals, the biological clock that generates circadian rhythms is located in the suprachiasmatic nucleus (SCN) of the hypothalamus. A system for automated, long-term monitoring of circadian firing rhythms from multiple SON neurons has been developed. In this dissociated culture system, cell interactions can be manipulated and individual rhythmic cells are accessible for further detailed study. With this system, single SCN neurons were shown to express circadian oscillations in firing rate for weeks. Despite abundant functional synapses, SCN neurons in the same culture expressed circadian rhythms of widely different phases, and even somewhat different circadian cycle lengths (periods). These data provide the strongest evidence to date that the SCN is composed of multiple circadian oscillators (clock cells).

Descriptors :   *CIRCADIAN RHYTHMS, *MAMMALS, OSCILLATORS, BIOLOGY, CLOCKS, MONITORING, INTERACTIONS, LONG RANGE(TIME), LENGTH, NERVE CELLS, OSCILLATION, CELLS(BIOLOGY), SYNAPSE, CULTURE, NUCLEI, FIRING RATE, HYPOTHALAMUS.

Subject Categories : Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE