A review of in vivo H-1 magnetic resonance spectroscopy of cerebral ischemia in rats

A number of metabolic alterations are initiated by cerebral ischemia includ ing dramatic increases in lactate concentration, decreases in N-acetylaspar tate, choline, and creatine concentrations, as well as changes in amino aci d levels. A review of proton nuclear magnetic resonance spectroscopy studie s of focal and global cerebral ischemia in rats is presented here. In parti cular, studies in neonatal rats have shown that a continued elevation of la ctate levels without recovery after hypoxia-ischemia or a decrease in N-ace tylaspartate concentration at any time are indicative of deleterious outcom e. Studies of the effect of temperature on ischemic damage in a model of fo cal ischemia showed that outcome improved with mild hypothermia. Again, lac k of recovery of lactate upon reperfusion was shown to be indicative of poo r outcome. Dichloroacetic acid was used to treat rats with focal ischemic d amage. Animals subjected to transient ischemia that were treated with dichl oroacetic acid showed significant decreases in lactate concentration.