Abstract
Endogenous machinery oscillating about 24hrs called circadian clock ticks internal body time and controls many physiological phenomena. The goal of circadian-modulated drug administration or "chronotherapy" is to find times for drug delivery that result in increasing main and reducing side effect. We still have difficulties to make transfer chronotherapeutic idea from laboratory to clinical situation, as we do not have highly sensitive and easily applicable method of each individual's body time detection yet. We've already invented "molecular time-table method" which utilize expression amount of cycling genes in target organ like liver to detect body time (Ueda et al., PNAS, 2004). To make this method more applicable, we decided to use blood because blood is frequently collected in hospitals. We collected mice blood every 4hr for two days under both light (12hrs)-dark and constant dark conditions. We detected more than 1,000 peaks of substances using capillary electrophoresis-time of flight mass spectrometry (CE-TOFMS), and we searched for corresponding peaks from samples to samples by informatics approach. We then selected cycling substances with statistical filters. As a next step, we tested whether we can detect the body time from simply one time-point sample by measuring the amount of cycling substances. We also asked whether the method works for detection of rhythm disorder. [J Physiol Sci. 2008;58 Suppl:S87]
