An experimental infectious diarrhoea model to assess intestinal myoelectrical activity

Abstract

Introduction: Diseases causing infectious diarrhoea, such as cholera, are a leading cause of childhood death and adult morbidity. At the level of enterocytes, cholera toxin (CT) – produced by Vibrio cholerae – induces a dramatic increase in electrolyte and water secretion by increasing intracellular cAMP and also by stimulating enteric nervous components. CT can modulate intestinal myoelectrical activity but its exact nature is not understood. One method used to assess this is high-resolution spatiotemporal electrical mapping. Aims and objectives: The study aimed to develop an animal model of cholera to assess myoelectrical activity in the gastrointestinal system. Materials and methods: Four young adult black mice were anaesthetized using pentobarbital (pentobarbitone) (pentobarbital sodium salt; Sigma-Aldrich) and jejunal loops were constructed. A total of 2μg of CT was instilled into the jejunal loops and incubated for 5 hours, after which the jejunal fluid was measured and jejunal sheets were used for slow-wave electrical recording for frequency, amplitude and velocity by fixing them in an organ bath using 121 mini electrodes. Results: CT-incubated animal jejuna showed significant fluid secretion after a period of 5 hours compared with the control group (CT group 1000μl vs. control group 100μl; P>0.001). The CT group showed an increase in slow-wave velocity compared with the controls and there was no change in frequency or amplitude. These are preliminary results and require further experimentation to confirm the significance. Conclusion: We have successfully developed an infectious model of diarrhoea, which can be utilized for myoelectrical recordings and analysis. Acknowledgements: We would like to acknowledge Dr Sandeep Subramanya, Dr Wim Lammers and Ms Betty Stephen, who helped us through this project.