Effect of pH on Metabolism and Ultrastructure of Guinea Pig Cerebral Cortex Slices

Lactic acidosis is a prominent biochemical alteration which follows cerebral ischemia and is of sufficient degree to result in pH decrease in involved and adjacent tissue. Because of the significance of acidosis in the cerebral ischemic process, we have investigated ultrastruclural changes and some biochemical parameters under varying pH conditions using guinea pig cerebral cortex slices. Metabolic rates decreased markedly during acidic incubations, and increased only minimally during basic incubations. Acidic pH affected oxygen and glucose utilization rates and fine structure to a greater degree than did an equal change in pH from 7.4 toward the alkaline. Glucose consumption was affected by pH deviations from 7.4 to a greater degree than oxygen uptake.