Fig. 2.

Effect of reserpine on glutathione (GSH) content of PC12 cells in the presence of cystine. PC12 cells, cultured for 2 d, were rinsed free of culture medium and incubated for 3 hr in a phosphate buffer (see Materials and Methods) at 37°C with 10, 30, or 100 μm cystine in the absence (control) or presence of 50 nm reserpine, respectively. Subsequently, the cells were lysed and the GSH and protein content in parallel cultures was determined as detailed in Materials and Methods. Data represent the mean ± SEM (n = 9) from three independent experiments. Between experiments, the GSH content after a 3 hr incubation in the absence of reserpine averaged from 0.7 to 2.0 nmol/mg protein (no cystine), 1.5 to 4.4 nmol/mg protein (10 μm cystine), 4.1 to 11.1 nmol/mg protein (30 μm cystine), and 8.7 to 18.3 nmol/mg protein (100 μm cystine). Therefore, the data are expressed as percentage of respective GSH content at each cystine concentration in the absence of reserpine. *p < 0.005 versus respective control.