Comparison of lactate concentration determinations in ischemic and hypoxic rat brains by in vivo and in vitro 1H NMR spectroscopy.

An experimental protocol for the quantitation of lactate is demonstrated for in vivo 1H NMR surface coil spectroscopy. The in vivo lactate concentration can be calculated by comparing the in vivo and in vitro ratios of lactate and N-acetylaspartate (NAA) NMR signals. With this protocol, approximately 25% of lactate present in the hypoxic or ischemic rat brain is observed by NMR.