Figure 3
From: Social interactions and olfactory cues are required for contagious itch in mice
Prior itch experience modulates look-scratch behavior. (A) Primed observer mice, pre-exposed to itch stimuli, with 100 µg/site of C48/80 one day before the experiment. Representative bar graphs show the mean number of (B) look-scratch, (C) looks, and (D) total scratching bouts of primed observer mice in comparison to mice without prior itch experience in the physical encounter (PE) and non-physical encounter (NPE) conditions (**** P < 0.0001 shows the comparison between primed and non-primed mice in the PE condition). E) Group 1: Observers got no pruritogen, paired with demonstrators receiving an effective C48/80 dose (100 µg/site). Group 2: Both observers and itch demonstrators got a sub-effective C48/80 dose (30 µg/site). Group 3: Observers got the sub-effective dose, while adjacent itch demonstrators received the effective dose (100 µg/site) of C48/80. Representative bar graphs of the mean number of (F) look-scratch, (G) looks, and (H) total scratching bouts of observer mice in different groups. The observer mice injected with the pruritogen exhibited a significant increase in both look-scratch responses compared to the observer that received no pruritogen (**** P < 0.0001 and #### P < 0.0001 pairwise comparisons). The total scratching bouts of pruritogen-injected mice were higher when paired with mice exhibiting scratching behavior ($$$$ P < 0.0001 compared C48/80 (30 µg/site) injected mice placed next to the demonstrator received 30 or 100 µg/site of C48/80, **** P < 0.0001 and #### P < 0.0001 compared C48/80-injected mice placed alone or next to a demonstrator with scratching activity. Values are presented as mean ± SEM. NS: not significant.
