Evidence of Presynaptic Localization and Function of the c-Jun N-Terminal Kinase

Figure 7

JNK inhibition reduces SNARE complex formation. (a) Western blotting and relative quantification of SNARE complex levels (anti-Syntaxin-1 immunoreactive bands from approximately 75 to 100 KDa) in 20 g of crude synaptosomes stimulated with NMDA 100 m and glycine 1 m for 7 min in presence or absence of D-JNKI1 (2 m), added to synaptosomes 25 min before stimulation. After NMDA/Gly exposure there was a significant increase in SNARE complexes formation (), which is totally prevented by D-JNKI1 preadministration (). SNARE complexes are normalized on actin, . Data are shown as mean ± SEM, Two-way ANOVA, Tukey's post hoc test. (b–d) Western blotting and relative quantification of Syntaxin-1, Syntaxin-2, and Snap25 in 20 g of crude synaptosomes stimulated with NMDA 100 m and glycine 1 m for 7 min in presence or absence of D-JNKI1 (2 m), added to synaptosomes 25 min before stimulation. There was no significant variation of protein levels after NMDA/Gly exposure as well as after D-JNKI1 administration alone or in combination with NMDA/Gly. Proteins are normalized on actin, . Two-way ANOVA, Tukey’s post hoc test. Data are shown as mean ± SEM.

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