Local cerebral glucose utilization in the neocortical areas of the rat brain

Abstract

The neocortex of the rat brain can be subdivided into regions of different local cerebral glucose utilization (LCGU). However, only a few neocortical areas can be delineated by differences in mean LCGUs between neighbouring areas. These area borders correspond exactly with cytoarchitectonically defined borders found in adjacent Nissl-stained preparations. On the other hand, nearly all of the architectonically defined area borders are also recognizable in the LCGU pictures, if differences in laminar distribution patterns of LCGU are taken into account. Furthermore, interareal differences in mean LCGU mainly reflect changes in layer IV, whereas layers II-III and V-VI show nearly identical LCGU values in all neocortical areas of the rat brain. The primary sensory areas exhibit the highest LCGU in layer IV, while the primary motor cortex shows a high LCGU in layer V. As the cytoarchitectonically defined pattern of the cortex is generally corroborated by the regional and laminar LCGU distribution, anatomical, metabolic and functional aspects of cortical architecture are associated.

Lack of Effects of Inhibition of Nitric Oxide Synthesis on Local Glucose Utilization in the Rat Brain

“…The hypothesis is that in LTP NO liberated from CAI pyramidal cells acts as a retrograde messenger to alter the presynaptic membrane in such a way as to facilitate neurotransmitter release. In the present study, 1CMR,,, in the molecular layer of hippocampus, which is composed of both the molecular-lacunosum layer of the hippocampal CAI -3 and the external limb of the dentate gyrus (Wree et al, 1988), did not show any changes following inhibition of brain NO synthase activity. In- 1.…”

Regional metabolic differences in rat prefrontal cortex measured with in vivo 1H‐MRS correlate with regional histochemical differences

“…If the higher Glu concentration in the mPFC voxel reflects higher regional glutamatergic activity, the energy consumption rate should be higher in the mPFC than in the pCG. Previous autoradiograph studies, however, reported similar cerebral glucose utilization rates (rCGU) in the two regions . The explanation for this apparent discrepancy probably lies in the fact that regional rCGU variations are not necessarily in parallel with the variations in regional cerebral metabolic rate of glucose oxidation (CMR glc(ox) ).…”

“…Previous autoradiograph studies, however, reported similar cerebral glucose utilization rates (rCGU) in the two regions. 50 The explanation for this apparent discrepancy probably lies in the fact that regional rCGU variations are not necessarily in parallel with the variations in regional cerebral metabolic rate of glucose oxidation (CMR glc(ox) ). For example, rCGU measured with autoradiography was reported to be 45% higher in the temporal cortex than in the parietal cortex in rats, 51 while CMR glc(ox) measured with ex vivo 13 C-MRS was 17% lower in the temporal cortex than in the parietal cortex.…”

Plasticity in the Rat Hippocampal Formation following Ibotenic Acid Lesion of the Septal Region: A Quantitative [14C]Deoxyglucose and Acetylcholinesterase Study

“…As the left CMRglc values of many hippocampal layers and areas turned out to be higher than the right CMRglc values (analyzed with the t test for matched pairs) and the lesion-induced effects were principally the same in both hemispheres, only the results of the left hemisphere are presented in detail. Moreover, we published the results of the left hemisphere before (Wree et al, 1988). For each of the brain regions, the CMRglc values of the four experimental groups were compared by one-way analysis of variance (ANOV A).…”