Effect of genetic background and postinfectious stress on visceral sensitivity in Citrobacter rodentium‐infected mice

Background Infectious gastroenteritis is a major risk factor to develop postinfectious irritable bowel syndrome (PI‐IBS). It remains unknown why only a subgroup of infected individuals develops PI‐IBS. We hypothesize that immunogenetic predisposition is an important risk factor. Hence, we studied the effect of Citrobacter rodentium infection on visceral sensitivity in Th1‐predominant C57BL/6 and Th2‐predominant Balb/c mice. Methods Eight‐week‐old mice were gavaged with C. rodentium, followed by 1 h of water avoidance stress (WAS) at 5 weeks PI. At 10, 14 days, and 5 weeks PI, samples were assessed for histology and inflammatory gene expression by RT‐qPCR. Visceral sensitivity was evaluated by visceromotor response recordings (VMR) to colorectal distension. Key Results Citrobacter rodentium evoked a comparable colonic inflammatory response at 14 days PI characterized by increased crypt length and upregulation of Th1/Th17 cytokine mRNA levels (puncorrected