Fig. 7.

Muscimol-dependent ERK activation relies on intracellular Ca²⁺ release and BDNF/TrkB pathways, in contrast with KCl depolarization. Neurons at DIV 13–15, all pretreatments were accompanied by matched vehicle controls (see Experimental Procedures) followed by 0 or 30 min muscimol treatment. A–E. Representative immunoblots with pERK immunoreactivity normalized to t0 with vehicle control. Mean ± SEM, n = 3–6 cultures, two way ANOVA and post hoc t-tests *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001. A. U0126 pretreatment. B. Nimodipine pretreatment (Nim). C. Neurons were muscimol treated in the presence of either normal extracellular Ca²⁺ in HBS (+Ca²) or HBS containing 0 mM Ca²⁺ and 1 mM EGTA (−Ca²). D. Synaptic stimulation protocol, neurons were briefly treated with KCl in the presence of either normal extracellular Ca²⁺ in HBS (+Ca²) or HBS containing 0 mM Ca²⁺ and 1 mM EGTA (−Ca²). E. Thapsigargin and BAPTA-AM pretreatment (TGBA). F. ANA 12 TrkB inhibitor pretreatment.