Local Cerebral Glucose Utilization in Chronic Middle Cerebral Artery Occlusion in the Cat

Abstract

Summary: This study examines the correlation between local CMRglc (LCMRglc) alterations and clinicopatholog ical changes in a chronic middle cerebral artery (MCA) occlusion model in the cat. The left MCA was occluded for a period of 2 h. The animals were grouped into mild, moderate, and severe ischemia based on the depression of the EEG 30 min after the MCA occlusion. Follow ing release of the clip, the animals were allowed to re cover for a week during which time daily neurological examinations were performed. On the seventh day P4C]2-deoxyglucose was injected for the determination of LCMRglc• Alternative blocks were processed for histo logical evaluation in which both neuronal and phagocytic changes were graded into four categories (0 = normal to 3 = severe). LCMRglc (J.LmollIOO glmin) in the ischemic hemisphere (all histological grades) was significantly lower than the metabolic rate in comparable regions of the sham MCA occlusion group. Regions with significant phagocytosis (grade 2 and 3) invariably exhibited acti vated glucose metabolism (57.4 ± 8.4 and 105.9 ± 6.8 J.Lmol/lOO glmin, respectively), which was significantlyThe recovery process of brain tissue after an isch emic insult may be closely related to its metabolic state. Although the recent development of positron emission tomography has offered the potential for investigating glucose metabolism of the human brain Phelps et al., 1982), few studies have been made early following a stroke (Kuhl et al., 1980;Lenzi et al., 1982;Wise et al., 1983;Baron et al., 1984;Kushner et al., 1987). These findings provided some information about Abbreviations used: 2-DG, 2-deoxyglucose; LC, lumped con stant; LCMRgl c, local CMRglc; MCA, middle cerebral artery. 535higher than in regions without phagocytosis (30.4 ± 0.8 J.LmolllOO g/min). There was a significant gradient of me tabolism in the central, peripheral, and boundary zone and the non-MCA territory in the animals with severe ischemic lesions. LCMRglc in the central MCA territory was well correlated with the EEG amplitude changes (r = 0.82, p < 0.05) and the morphological score (r = -0.89, p < 0.05). The metabolic rate was significantly depressed in both the ipsilateral and the contralateral central MCA territories in comparison with the sham occlusion ani mals. The depression in LCMRglc in the contralateral hemisphere correlated well with the concomitant depres sion in the contralateral EEG amplitude. These studies demonstrate that local heterogeneous metabolic alter ations and contralateral cortical diaschisis exist chroni cally following temporary MCA occlusion and that the increases in local cerebral glucose metabolism seen in chronic stroke may be due to phagocytotic activity.

Lactate production by human monocytes/macrophages determined by proton mr spectroscopy

“…This study found that voxels showing low N-acetyl aspartate and high lactate were associated with histopathological sections containing macrophages (10). Other studies of focal CMRglc in an animal model of stroke have shown an increase in glucose metabolism that correlates highly with the histopathological finding of macrophage infiltration (16).…”

Postischemic Neuronal Damage Causes Astroglial Activation and Increase in Local Cerebral Glucose Utilization of Rat Hippocampus

“…However, other possible reasons for increases in CMR g lc in postischemic brain tissue are also known. Recently, Komatsumoto et al (1989) dem onstrated an increase in CMR g lc caused by phago cytes 7 days after transient occlusion of the middle cerebral artery in the cat. Dietrich et al (1 986b ) have reported a hypermetabolic zone coincident with foci of intense macrophage infiltration 5 days after photochemically induced cortical infarction in the rat.…”

Nefiracetam Improves the Impairment of Local Cerebral Blood Flow and Glucose Utilization after Chronic Focal Cerebral Ischemia in Rats

“…Also, the arterial blood pressure, arterial blood gases (pH, PCO 2 , PO 2 and glucose in blood), and body temperature did not change during the chronic postischemic period in the four-vessel occlusion model in conscious rats [21,22]. Furthermore, arterial blood pressure and arterial blood gases showed no significant differences between the MCA-occluded group and the sham group during the measurement of cerebral glucose utilization at 7 days after MCA occlusion in the cat [23]. Thus, we assumed that the physiological parameters were unchanged during the measurement of LCBF and LCMR glc in this study.…”