Cerebral Glucose Utilization in Rats is Not Altered by Hindlimb Restraint or by Femoral Artery and Vein Cannulation

Abstract

The effects of immobilization and femoral artery and vein cannulation on resting rates of local cerebral glucose utilization (LCGU) were measured in 35 brain regions of awake rats by using the quantitative, autoradiographic [14C]2-deoxy-D-glucose [( 14C]DG) technique. Three groups of rats were cannulated on the previous day, and LCGU was measured under conditions of no restraint, 4 h of hindlimb restraint, or acute, four-limb immobilization. A fourth group represented the conventional preparation for [14C]DG experiments, with same-day cannulation followed immediately by 4 h of hindlimb restraint. Plasma catecholamines, corticosterone, and glucose concentrations were measured in all groups; all were elevated significantly above values in unrestrained animals only during four-limb immobilization. LCGU was unchanged by same-day surgery, hindlimb restraint, or both. During four-limb immobilization, LCGU was reduced by 25% in the dorsal hippocampus, and to a lesser extent in the anteroventral thalamic nucleus. It was increased only in the lateral habenula (42%). We conclude that two stressors of the experimental preparation (same-day surgery and hindlimb restraint) do not influence LCGU measurements by the [14C]DG method. More severe, acute stress selectively alters LCGU in a few rat brain regions.

Detection of Visual Activation in the Rat Brain Using 2-deoxy-2-[18F]fluoro-d-glucose and Statistical Parametric Mapping (SPM)

“…Therefore, afferents from the superior colliculus project to the visual thalamus. Toga et al [44,45] found that the metabolic changes were greatest in the superior colliculus, less so in the lateral geniculate, and considerably less in second-order sites such as layer IV of the visual cortex. Moreover, these changes were frequency dependent in the superior colliculus and lateral geniculate, showing a greater metabolic rate at higher frequencies of stimulation.…”

“…The possible effects of immobilization stress on the local cerebral metabolic rate of glucose has been investigated elsewhere, and no significant differences were found either [44,45].…”

In vivo imaging of disturbed pre- and post-synaptic dopaminergic signaling via arachidonic acid in a rat model of Parkinson's disease

“…k* is unaffected by changes in cerebral blood flow that might be affected by drugs or stress, thus reflects only changes in brain AA metabolism. The method is presented in detail elsewhere (Bhattacharjee et al, 2005;Chang et al, 1997;DeGeorge et al, 1991;Hayakawa et al, 2001;Ohata et al, 1982;Rapoport, 2003;Robinson et al, 1992;Soncrant et al, 1988). With it, we showed in unlesioned unanesthetized rats that acute administration of quinpirole, a D 2 -receptor agonist, increased k* for AA in brain regions with high densities of D 2 -receptors, and that the increases could be blocked by the preferential D 2 -receptor antagonist, butaclamol (Bhattacharjee et al, 2005;Bristow et al, 1998;Hayakawa et al, 2001).…”

Thiopentone induced enhancement of somatic motor responses to noxious stimulation: influence of GABAA receptor modulation

“…22 The effects of partial restraint upon the somatic motor response were evaluated by comparing SMRT measurements made in 29 unrestrained animals with values obtained once the animals were instrumented and partially restrained. Twenty of these animals were entered into Protocol 2 while nine were not studied further.…”