Evaluation of gastrointestinal motility in awake rats: report of our experience

The current medical curriculum in the School of Medicine at the University of San Luis Potosi, Mexico, includes experiments on physiology in animal models. The purpose of the present work was to evaluate the feasibility to establish, as a regular lab practice for second year medical students taking the Human Physiology course, a recently published “hands on” activity to assess gut motility in rats1 (Adv.Physiol. Edu.33:343–348, 2009). Here we report preliminary experiments performed to prove the reproducibility of the results published previously1. We evaluated gastric emptying and intestinal motility after administrating a hypertonic bolus or under hypoglycemia conditions. We used the fractional recovery of the phenol red dye method1 in the stomach and in the proximal, middle and distal portions of the small intestine of male Wistar rats to reach our objective. We found significant differences between the hypertonic group and the control group only 20 min after the injection of the bolus. However the hypoglycemic group did not show differences with the control group at any time. Hypertonic bolus does accelerate the gastric emptying but not intestinal motility, whereas the hypoglycemia does not accelerate either the gastric emptying or the intestinal motility. In our hands we found extremely technically difficult to reproduce Souza's results. Supported by UASLP C10‐PIFI‐09‐15.44 to RET.