Developmental alcohol and circadian clock function

Studies in rats found that alcohol exposure during the early postnatal peri od, particularly during the brain-growth-spurt period, can result in cell l oss in various brain regions and persistent behavioral impairments. Some in vestigators have speculated that the body's internal clock, which is locate d in the suprachiasmatic nuclei (SCN) in the brain, may also be affected by developmental alcohol exposure. For example, alcohol-induced damage to the SCN cells and their function could result in disturbances of the circadian timekeeping function, and these disturbances might contribute to the behav ioral impairments and affective disorders observed in people prenatally exp osed to alcohol. Preliminary findings of studies conducted in rats suggest that developmental alcohol exposure may indeed interfere with circadian clo ck function as evidenced by a shortened circadian sleep-wake cycle and chan ges in the release of certain brain chemicals (i.e., neuropeptides) by SCN cells.