Carnosine and taurine protect rat cerebellar granular cells from free radical damage

Carnosine and taurine have been suggested to protect excitable tissues agai nst oxidative stress. We have investigated the protection of cerebellar gra nule cells (neurons) by these compounds against free radicals generated by kainic acid (KA), and 3-morpholinosydnonimine hydrochloride (SIN-1) treatme nt. Carnosine decreased free radical levels in KA and SIN-1 treated cells, and increased cell viability. The KA effect, but not that of SIN-I, was dep endent on the presence of external Ca2+ ions. Taurine increased cell viabil ity, but did not decrease free radical levers. These results suggest that t here are multiple pathways leading to cell death, not all of which involve decreases in intracellular free radical levels, and also indicate that mult iple mechanisms of cellular defense exist against oxidative stress. (C) 199 9 Elsevier Science Ireland Ltd. All rights reserved.