Fig. 6.

Effect of loperamide and eluxadoline on castor oil-induced body weight change. Diarrhea was induced by oral administration of castor oil (0.6 ml/mouse) in WT (A) or δOR^−/− (B) mice. Body weight was measured before and 4 h after castor oil administration. Loperamide and eluxadoline (5 or 10 mg/kg) were administered orally 15 min before the castor oil administration. Naltrexone (10 mg/kg, i.p.) was administered 20 min before loperamide or eluxadoline administration. Results are the mean ± S.E.M. n = 3–6. **p < 0.01, vs. vehicle control; ##p < 0.01, vs. castor oil alone; $$p < 0.01, vs. castor-oil + loperamide (10 mg/kg, p.o.); †p < 0.05, ††p < 0.01, vs. castor oil + eluxadoline (10 mg/kg, p.o), Student–Newman–Keuls test.