Altered circadian rhythmicity is an early sign of murine dietary thiamine deficiency

To determine if circadian clock function is affected by thiamine deficiency , the rhythm of locomotor (wheel-running) activity was measured in a murine model of dietary thiamine deficiency. About 1 month before the expected on set of overt neurological illness, locomotor rhythmicity in deficient anima ls exhibited a shortened free-running period without a change in amplitude. This effect was fully reversible by thiamine administration. Disordered ci rcadian timekeeping may contribute to altered physiological responses in We rnicke's encephalopathy. (C) 1999 Elsevier Science B.V. All rights reserved .