Regional quantitative determination of lactate in brain sections. A bioluminescent approach.

Regional lactate distribution in brain was assessed quantitatively in coronal sections using a bioluminescent technique. This bioluminescence can be induced by covering freeze-dried and heat-inactivated brain sections with a frozen solution containing enzymes and coenzymes both for lactate-dependent NADH formation and NADH-dependent bioluminescence, which was recorded photographically. Quantification and density coding of bioluminescent images were carried out by utilizing the regression coefficients of the correlation between the optical density of bioluminescent pictures and the lactate content measured in tissue samples. Regional quantitative lactate images were obtained from brain tissue taken from brain tumors or after experimental cerebral ischemia.