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. Author manuscript; available in PMC: 2010 Sep 1.
Published in final edited form as: Pain. 2009 Jun 26;145(1-2):120–128. doi: 10.1016/j.pain.2009.05.025

Figure 1. Comparison of EMG and behavioral responses to 60-mmHg colorectal distension in female and male rats.

Figure 1

(A) Experimental protocol. Time course of EMG activity (B) and behavioral pain posturing (C) before and during colorectal distension (CRD) in female and male rats (n = 10 - 12). (D) Area under curve computed over the 40-s period after the onset of CRD for EMG activity normalized to the 40-s baseline before CRD. Two-way ANOVA revealed significant main effect of CRD (F1,41 = 63.6, P < 0.0005), but not of Sex (F1,41 = 0.6, P = 0.5) or of the Sex × CRD interaction (F1,41 = 0.5, P = 0.5). (D) Percentage of time animals spent in pain postures during the 40-s period after CRD onset. Rats exposed to 60-mmHg CRD spent significantly more time in pain postures than 0-mmHg controls (CRD effect: F1,42 = 299.0, P < 0.0005, two-way ANOVA). Pain scores were significantly higher in female than in male rats (Sex effect: F1,42 = 5.1, P < 0.05). There was no significant Sex × CRD interaction (F1,42 = 0.5, P = 0.5). Results of the two male groups were reproduced from Wang et al. [50] with permission.