ACIDOSIS REDUCES NEURONAL APOPTOSIS

ACIDOSIS is a well established concomitant of tissue ischemia. Acidosi s in the pH range 6.0-7.0 is seen in cerebral ischemia and within soli d tumors. Extracellular acidosis of pH 6.0 and 6.4 provided essentiall y complete protection from 48 h serum deprivation induced apoptotic de ath of cultured primary murine neurons. We tested the effect of p53 us ing transformed mouse embryo fibroblasts of either p53+/+ or p53(-/-) genotype. Both were markedly protected from serum deprivation by acidi ty. Hypoxia induced fibroblast injury was also reduced at pH 6.8. Lowe r pH resulted in a shift from apoptotic to necrotic morphology after 4 2 h hypoxia. Acidosis reduces apoptosis of both normal and transformed cells, irrespective of p53 status. (C) 1998 Rapid Science Ltd.