Fig. 4. Inhibitory effects of the ER Ca2+-ATPase inhibitor thapsigargin, the IP3 receptor antagonist 2-APB, and the ryanodine receptor antagonist dantrolene on low [Mg2+]o-induced epileptiform activity.
(A1) Exposure to Mg2+-free ACSF induced epileptiform activity in the CA1 region of acute hippocampal slices. Thapsigargin (10 μM), which induces depletion of ER Ca2+ stores, significantly inhibited the spike firing and amplitude of low [Mg2+]o-induced epileptiform activity. (A2) Graph summarizes the spike firing and amplitude of the epileptiform activity in non (control, n = 6)-, thapsigargin (n = 6)-treated groups. (B1) IP3 receptor antagonist 2-APB (30 μM) and ryanodine receptor antagonist dantrolene (30 μM) significantly inhibited the spike firing of low [Mg2+]o-induced epileptiform activity. (B2) Graph summarizes the spike firing and amplitude of the epileptiform activity in non (control, n = 8)-, 2-APB (n = 6)-, and dantrolene (n = 6)-treated groups. Data are expressed as means ± SEM. ER, endoplasmic reticulum; IP3, inositol-1,4,5-trisphosphate; 2-APB, 2-aminoethoxydiphenyl borate; [Mg2+]o, extracellular Mg2+ concentration; ACSF, artificial cerebrospinal fluid. *p < 0.05 relative to respective control (non-paired Student’s t-test), **p < 0.01 relative to respective control (non-paired Student’s t-test), #p < 0.05 relative to respective control (one way ANOVA with Bonferroni’s test).
© Korean J Physiol Pharmacol
