Fig. 2. Effects of extracellular magnesium on GSH concentration. Concentration-dependent analysis in three primary cultures of human hepatocytes (HH2, HH3 and HH4) and cultures of rat hepatocytes (RH, expressed as means + SEM, n = 3 different hepatocyte cultures, means without a common letter (a, b, c) differ p 0.05) exposed to 0, 0.2, 0.4 and 0.8 mM magnesium for 72 h. GSH concentrations in the 0.8 mM condition are 48.7, 66.5, 30.4 and 23.8 nmol/mg protein for HH2, HH3, HH4 and RH, respectively.