Fig. 1.

Effects of SNAP and LNNA on the viability of INS-1 pancreatic cells. a SNAP produced a concentration-dependent reduction in the survival rate of the INS-1 pancreatic cells. As the time of the exposure increased from 24 to 72 h, fewer cells survived (n = 3, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, P values refer to the differences in concentrations compared with control conditions). b The presence of LNNA produced differential effects on the survival of the INS-1 pancreatic cells. Short exposure to two different concentrations of LNNA (100 and 200 μM) produced a reduction in the survival of the cells but this pattern was reversed as the time of exposure increased. Exposure for 72 h of LNNA (100 and 200 μM) increased the survival of the of the INS-1 pancreatic cells (n = 3, *P < 0.05, ***P < 0.001, ****P < 0.0001, P values refer to the differences in concentrations compared with control conditions). All values are expressed as ± SE. Abbreviations: INS-1, insulin-producing pancreatic cells; LNNA, L-NG-nitro-l-arginine; NS, not significant; SNAP, S-nitroso-N-acetylpenicillamine