Influence of in vitro lactic acidosis on central nervous system neurons.

Central nervous system (CNS) cultured neurons while exposed to different concentrations and pH of L-lactic acid exhibited in general chromatin clumping, vacuolization in the cytoplasm, appearance of lipid bodies, accumulation of polyribosomes, cytoplasmic lucency and swollen and aggregation of mitochondria. These alterations progressed with lower pH and longer exposure to lactic acid. At pH 7.4, there was no considerable pathologic changes in cultured neurons irrespective to concentrations of lactic acid added. Comparable results were obtained with the use of other weak acid (citric acid) indicating that the observed changes were due to acidic pH rather than lactate per se.