Focal Ischemia of the Rat Brain: Autoradiographic Determination of Cerebral Glucose Utilization, Glucose Content, and Blood Flow

Abstract

Focal cerebral ischemia was induced in rats by occlusion of the middle cerebral artery. By a triple-tracer technique, cerebral glucose utilization, glucose content, and blood flow were simultaneously determined. Computer-assisted autoradiography revealed a core of dense ischemia in the lateral two-thirds of the striatum. A border zone of increased 2-deoxy-d-glucose (DG) uptake surrounded the ischemic insult in the acute stage. The lumped constant was increased only moderately in the border zone. Therefore, the enhanced DG uptake reflected increased glucose consumption. CBF was reduced to 20–30% in the cortical border, while minor depression and in some animals hyperemia were evident in the striate border. Six hours after the insult, the border zones of increased glucose consumption had disappeared in half the animals. In no animals examined after 20 h was glucose consumption enhanced. The study indicated a stable metabolic response to a reproducible focal insult. We conclude that continued enhancement of glucose consumption in marginally perfused areas indicates neuronal damage.