The role of lactic acidosis in the ischemic nerve cell injury.

Severe incomplete cerebral ischemia of 30 min duration with CBF below 5% of normal was induced in rats by clamping both carotids and lowering BP. One group of rats were fasting (f-rats), while the other was infused with glucose before induction of the ischemia (g-rats). In f-rats the lactate accumulating in the cerebral cortex was about 15 mumol . g-1, whereas in g-rats it rose to about 35 mumol . g-1. In f-rats considerable recovery of the energy state and electrical activity occurred during recirculation, whereas in g-rats the energy failure persisted with no electrical activity reappearing. In f-rats the structural alterations were of minor severity, but in g-rats extensive progressive tissue damage was seen. The data indicate that the degree of tissue lactic acidosis has pronounced effects on the development of irreversible ischemic nerve cells injury.