Figure 1. Induction but not expression of AD-ITM requires MAPK activity, and combined KCl depolarization and 5HT application activates MAPK.

A. The semi-intact preparation used to monitor T-SWR in the presence of pharmacological agents (shaded area). B₁. The MEK inhibitor, U0126 (20µM; n=5) or its inactive analog, U0124 (20uM; n=6) were applied to the ring ganglia 1 hour before 1xTS and were present throughout the remainder of the experiment. B₂. Summary data of 30–90 min time points combined. Within-group analysis revealed significant AD-ITM in controls, but not in groups treated with UO126, and a between group test revealed a significance difference. In this and subsequent figures, data are expressed as means ±SEM. C₁. The MEK inhibitor, U0126 (20µM; n=6) or its inactive analog, U0124 (20uM; n=8) were applied to the ring ganglia immediately after 1xTS and were present throughout the remainder of the experiment. C₂. Summary data in which intermediate time points 30–90 min were combined. Both groups exhibited significant AD-ITM; there was no significant difference between groups. D₁. The treated pleural-pedal pair received i) a single pulse of 5HT (50µM, 5min; n=8), ii) a single pulse of high KCl ASW (100mM, 5 min; n=10), or iii) a combination of KCl and 5HT (KCl first, 2 min overlap with 5HT; n=11). Control side remained in ASW to establish a within-animal baseline (see Methods). Quantification of MAPK activation is represented as the ratio of phospho-MAPK (P-MAPK)/ total MAPK (MAPK) between the two sides (see Methods). D₂. Summary data showing that only the combination of KCl+5HT produced significant MAPK activation. E. Pleural-Pedal pairs were divided and one side was stimulated with the analog (KCl+5HT). Sensory clusters were harvested at the indicated times. Within sample t-tests revealed that MAPK was significantly activated by the associative analog at each time point (p<0.05).