Volume 115, Issue 5, Pages 1123-1130 (November 1998) Inhibitory effect of somatostatin on Helicobacter pylori proliferation in vitro  Koichi Yamashita, Hiroshi Kaneko, Sayuri Yamamoto, Toshihiro Konagaya, Kazuo Kusugami, Terunori Mitsuma  Gastroenterology  Volume 115, Issue 5, Pages 1123-1130 (November 1998) DOI: 10.1016/S0016-5085(98)70083-6 Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 1 Growth curves for (A) H. pylori (ATCC 43504) and (B) E. coli (ATCC 11775). Bacteria were cultured in 5 mL Brucella broth containing 7% FBS at 37°C in a microaerobic atmosphere. Viable bacteria number (CFU/mL) in each time was calculated by counting the colonies on the agar at serial log dilution of the broth containing bacteria. Gastroenterology 1998 115, 1123-1130DOI: (10.1016/S0016-5085(98)70083-6) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 2 Effect of chemicals on H. pylori or E. coli proliferation. H. pylori (ATCC 43504, 103 CFU/mL) or E. coli (ATCC 11775) was cultured in 5 mL Brucella broth containing 7% FBS at 37°C in a microaerobic atmosphere. Chemicals (10−14 to 10−6 mol/L) were dissolved in absolute methanol and added into the broth at a final methanol concentration of 1%. Bacterial number (CFU/mL) was calculated after 48 hours of incubation for H. pylori and 5 hours for E. coli by counting the colonies on the blood agar and is shown on the y axis. (A) Somatostatin, (B) gastrin I, (C) 8-bromo-cGMP, (D) dbcAMP, and (E) somatostatin on E. coli. Each bar represents the mean ± SEM of number of samples shown at the top of each column. *P < 0.01 compared with respective vehicle (Bonferroni test). Gastroenterology 1998 115, 1123-1130DOI: (10.1016/S0016-5085(98)70083-6) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 3 Effect of anti–somatostatin 14 antibody IgG fraction on somatostatin-induced suppression in H. pylori proliferation. ATCC 43504 was inoculated in the Brucella broth containing the purified IgG fraction from antisomatostatin polyclonal antibody (somatostatin antibody, 1 μg/mL) or from nonimmune rabbit sera (control antibody, 1 μg/mL) with somatostatin (10−11 mol/L; ■) or vehicle (2) for 48 hours. Each bar represents the mean ± SEM of 6 samples. *P < 0.05 compared with respective vehicle; #P < 0.05 compared with control antibody plus somatostatin (Bonferroni test). Gastroenterology 1998 115, 1123-1130DOI: (10.1016/S0016-5085(98)70083-6) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 4 Microscopic findings of ATCC 43504. The morphology 48 hours after inoculation with either (A) vehicle or (B) somatostatin (10−11 mol/L) was checked by Gram-staining smears. (C) Coccoid conversion was induced by keeping the bacteria in the water for 10 hours at room temperature. Bar = 10 μm. Gastroenterology 1998 115, 1123-1130DOI: (10.1016/S0016-5085(98)70083-6) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 5 Effect of somatostatin on cAMP and cGMP levels in H. pylori. ATCC 43504 was cultured in the Brucella broth with either somatostatin (10−11 mol/L; ■) or vehicle (2) for 48 hours. The pellet was suspended in 0.1 mol/L HCl at 1 mL and was sonicated intensively for 3 minutes on ice. Bacterial cAMP/cGMP concentrations in the supernatant were measured by radioimmunoassay. Levels of cAMP/cGMP are expressed as fmol/109 CFU. Each bar represents the mean ± SEM of 4 samples. *P < 0.01 compared with respective vehicle (Bonferroni test). Gastroenterology 1998 115, 1123-1130DOI: (10.1016/S0016-5085(98)70083-6) Copyright © 1998 American Gastroenterological Association Terms and Conditions