Figure 7.

miR transcription is required for the DA-dependent persistent increase in LP I_hG_max. (A) The Ago hook blocks the persistent increase in LP I_A G_max elicited by 5 nM DA. The Ago hook injection experiments described in Figure 5A were repeated without TTX, and LP I_A G_max was measured. Each symbol represents one experiment, and the horizontal bars represent the means. The asterisk indicates a significant difference between the saline and DA-treated preparations, as determined using Student t-tests for the non-injected preparations (p < 0.006) and the hook-injected preparations (p = 0.244). (B) Flavopiridol (100 nM) blocked the persistent increase in LP I_A G_max elicited by 5 µM DA. Experiments diagrammed in Figure 6A were repeated with flavopiridol except that LP I_A was measured and plotted for each treatment group. Each symbol is one experiment; horizontal bars are the means. Asterisk indicates a significant difference as determined using t-tests to compare DA and saline treatment groups in preparations with (p = 0.969) and without (p = 0.004) flavopiridol. Note that unequal variances between +/− flavopiridol groups prevented analysis with an ANOVA (F-test, p < 0.008). (C) Actinomycin D (50 µM) blocked the persistent increase in LP I_A G_max elicited by 5 µM DA. Experiments diagrammed in Figure 6A were repeated with Actinomycin D, except that LP I_A was measured and plotted for each treatment group. Each symbol is one experiment; horizontal bars are the means. Asterisks indicate significant differences as determined using a Kruskal-Wallis test with Dunn’s multiple comparison posthoc tests, p = 0.0014.