Local cerebral glucose utilization in the free moving mouse: a comparison during two stages of the activity-rest cycle.

The 2-deoxy-D[1-14C]glucose ([14C]DG) technique has been applied to the free moving mouse for the quantitative determination of local cerebral glucose utilization (LCGU). Reproducible values for LCGU were obtained indicating that the [14C]DG method had a sufficient resolution power to allow visualization and quantification of very small structures provided that glucose and [14C]DG plasma concentrations were measured on microsamples, autoradiographs prepared from proper tissue sections and suitable techniques used for analysis of the maps thus obtained. LCGU was measured in free moving mice during two stages of the light-dark cycle, one corresponding to a period of rest and the other to a period of high motor activity. In the two groups of animals LCGU was heterogeneous in the grey matter, the highest values being found in the auditory regions, the cerebellar and vestibular nuclei. LCGU was found to be lower in drowsy animals during the day than in active animals during the night and the difference was significant in the 8 following structures: the sensorimotor cortex, the septal nuclei, the nucleus of the olfactory tract, the basal amygdaloid nucleus, the ventral nucleus of the thalamus, the lateral geniculate body, the medial geniculate body and the auditory cortex. On the contrary, the suprachiasmatic nucleus was very active during the day and relatively inactive during the night as previously reported in the rat.