Increase in the number of PS bouts after ICV administration of MCH. Histograms illustrating the number of PS bouts (A) and their duration (B) during the first four hours following ICV administration of NaCl, 0.02, 0.2,1, 5 or 10 μg of MCH (mean ± SEM). There is a significant difference in the number of PS bouts between NaCl and MCH injections for 0.2, 1 and 5 μg. No difference in PS bouts duration was observed. Significance values indicated are for MCH versus NaCl injections ( *p < 0.05, **p < 0.01, ***p < 0.001).