Evaluation of combined antibiotic-omeprazole therapies in Helicobacter pylori-infected Mongolian gerbils

Mongolian gerbils are a laboratory host for gastric colonization with Helicobacter pylori, showing gastritis followed by typical gastric ulcer after infection with H. pylori. In such gerbils, we evaluated combined therapies of amoxicillin (AMPC) and clarithromycin (CAM) as antibiotics, and omeprazole (OPZ) as a H⁺/K⁺ adenosine triphosphatase (ATPase) inhibitor. The gerbils were orally inoculated with 2 × 10⁸ bacilli of ^{H. pylori} ATCC 43504. Four weeks after inoculation, the infected gerbils were orally treated singly with OPZ, AMPC, and CAM, and their insufficient efficacy on bacterial clearance was confirmed by a polymerase chain reaction technique, and by a culture method. In contrast, combined therapy of OPZ plus either AMPC or CAM showed significant bacterial clearance, demonstrating the efficacy of this combined therapy in the gerbil model. Mongolian gerbils are suggested to be useful for the pharmacological evaluation of anti-H. pylori compounds. Received Mar. 11, 1997; accepted June 27, 1997