Figure 3.

Glu/Gly-induced [Zn²⁺]_i elevations are Ca²⁺- and Na⁺-dependent. The effects of Glu/Gly on Fura-2FF (red) and FluoZin-3 (blue) fluorescence in hippocampal neurons were monitored as explained in Fig. 1, under Na⁺-free conditions with Na⁺ substituted with NMDG⁺ (a–c) or in the presence of 158 mM Na⁺ (d). In (a) and (d), 1.3 mM CaCl₂ was present in the medium. In (b), Ca²⁺ was omitted from the medium and 0.1 mM EGTA was added. In (c), the medium contained 1.3 mM CaCl₂ and 1 mM CaEDTA. The y-axes and the 5-min time bar apply to all panels. The data are means ± standard error from the indicated number of neurons monitored in a single experiment. All experiments were repeated at least 3 times with similar results. Panels (e) and (f) show Fura-2FF and FluoZin-3 signals, respectively, measured at the end of the 5th minute of Glu/Gly application. The data are means ± standard errors from 47 – 99 individual neurons (3 to 5 separate experiments). ** p < 0.01 versus Na⁺-free conditions; Kruskal-Wallis one-way ANOVA on Ranks followed by Dunn's test.