Yano et al Page 18 A A+5-HT B GF+CONV. SPEMARx p,48 C GF cony 于93 SPF abx D sPF GF P21 P42 P2. P42 sp -Sp CONV SPF+ABX Figure 2. Indigenous Spore-forming Bacteria Increase 5-HT Levels in Colon Enterochromaffin Cells (A)Representative images of colons stained for chromagranin A(CgA)(left), 5-HT(center) and merged (right). Arrows indicate CgA-positive cells that lack 5-HT staining. n=3-7 mice/ group (B) Quantitation of 5-HT+ cell number per area of colonic epithelial tissue. n=3-7 mice/ (C) Quantitation of CgA+ cell number per area of colonic epithelial tissue. n=3-7 mice/ group (D)Ratio of 5-HT+ cells/CgA+ cells per area of colonic epithelial tissue. n=3-7 mice/group Data are presented as mean+ sEM. *p<0.05, **p<0.01, ***p<0.001, ****p<00001 SPF=specific pathogen-free(conventionally-colonized), GF=germ-free, CONV=SPF conventionalized, ABX=antibiotic-treated, Sp=spore-forming bacteria, PCPA=para- Cell. Author manuscript; available in PMC 2016 April 09Figure 2. Indigenous Spore-forming Bacteria Increase 5-HT Levels in Colon Enterochromaffin Cells (A) Representative images of colons stained for chromagranin A (CgA) (left), 5-HT (center) and merged (right). Arrows indicate CgA-positive cells that lack 5-HT staining. n=3–7 mice/ group. (B) Quantitation of 5-HT+ cell number per area of colonic epithelial tissue. n=3–7 mice/ group. (C) Quantitation of CgA+ cell number per area of colonic epithelial tissue. n=3–7 mice/ group. (D) Ratio of 5-HT+ cells/CgA+ cells per area of colonic epithelial tissue. n=3–7 mice/group. Data are presented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. SPF=specific pathogen-free (conventionally-colonized), GF=germ-free, CONV.=SPF conventionalized, ABX=antibiotic-treated, Sp=spore-forming bacteria, PCPA=para￾chlorophenylalanine. See also Figure S2. Yano et al. Page 18 Cell. Author manuscript; available in PMC 2016 April 09. Author Manuscript Author Manuscript Author Manuscript Author Manuscript