Perfusion of the Functioning Portion of the Small Intestine of the Rats: Parameters of Perfusion and Dependence of the Velocity of Absorption of Glucose on the Velocity of Perfusion

Abstract

Objectives and method: To research the parameters of perfusion of the functioning portion of the rats′ small intestine in the chronic experiments under physiological condition without operation trauma, pain, narcosis and atrophy of the small intestine. To determine the volumes of the outflowing perfusate and the dependence of the velocity of glucose absorption in the functioning portion of the rats′ small intestine on the rate of its perfusion. Results: At perfusion of the functioning portion of the small intestine of rats for each 5 min it is possible to collect 50-70% of the perfusion solution introduced into the researching area. The volume of outflowing perfusate is largely determined by peristalsis, by the degree of satiety of the animal and by its functional state. In the range of the changing of the rate of perfusion from 0.37 to 2.61 ml/min the velocity of absorption of glucose from its 25 mmol/l solution changes from 7.63 ± 0.38 to 10.33 ± 1.90 mcmol/min and concentration of unabsorbed marker PEG changes from 102.89 ± 0.87 to 98.28 ± 1.85% correspondingly. The minimal velocity of glucose absorption and minimal concentration of PEG were detected under the velocity of perfusion 5.39 ± 0.36 ml/min: 1.12 ± 2.28 mcmol/min and 95.07 ± 2.93% correspondingly. In the range of the rate of perfusion from 0.37 ± 0.01 to 1.43 ± 0.04 ml/min there were detected absorption of water from the perfusate. Dilution of the perfusate starts only under the rate of perfusion 2.61 ± 0.04 ml/min and increases under the 5.39 ± 0.36 ml/min. Conclusions: The volume of outflowing from the functioning portion of the rats’ small intestine perfusate is largely determined by peristalsis, by the degree of satiety of the animal and its functional state. The velocity of glucose absorption from its 25 mmol/l solution in the functioning portion of the rats′ small intestine is not very sensitive to the rate of the perfusion in the range from 0.37 ± 0.01 to 2.61 ± 0.04 ml/min: it changes on 26% at the changing of the rate of perfusion on 86%.