Figure 1

METH induces microglial cell death. (A) METH increased the number of TUNEL-positive cells in a concentration-dependent manner (0.1 to 4 mM for 24 h), and Z-VAD (25 μM) completely prevented the apoptotic cell death induced by 1 mM METH. The results are expressed as percentage of total cells ± SEM (n = 10 to 25). ^*** P <0.001, Dunnett’s multiple comparison test, significantly different when compared to control. ⁺⁺⁺ P <0.001 to Bonferroni’s multiple comparison test, significantly different comparing with 1 mM METH. (B) Representative fluorescence images of TUNEL-positive cells following treatment with 0.1, 1 or 4 mM METH. Scale bar, 20 μm. METH: methamphetamine; SEM: standard error of the mean; TUNEL: terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay; Z-VAD: z-Val-Ala-DL-Asp (OMe)-fluoromethylketone.