Anxiolytic effect of Bifidobacterium longum during dextran sodium sulfate (DSS) colitis requires the integrity of the vagus. (A) Latency to step down from the elevated platform in control vagotomized mice (water, n = 14), vagotomized mice treated with DSS + CM (n = 15) and vagotomized mice treated with DSS + B. longum (n = 15). Vagotomy was performed before the third cycle of DSS. (B) Histology composite score in control vagotomized mice (water), vagotomized mice treated with DSS + CM and vagotomized mice treated with DSS and B. longum. (C). Myeloperoxidase activity in colon tissue of in control vagotomized mice (water), vagotomized mice treated with DSS + CM and vagotomized mice treated with DSS and B. longum. Individual values are shown. (D) Latency to step down from the elevated platform in control mice (water, n = 6), mice treated with B. longum (n = 6) and vagotomized mice (Vx) treated with B. longum (n = 15). Bars indicate mean (*P < 0.05 vs water).