Electrophysiological Evaluation for Conditions of Preservation of Isolated Human Colon Tissues

Abstract

The aim of the present study was to examine conditions for preserving isolated human colon tissues when assessing colonic drug absorption. Isolated human colon tissues were kept in various conditions. And electrophysiological analysis at 37°C was then carried out to assess the integrity of the paracellular and transcellular route using Ussing-type chambers. The membrane resistance (Rm) of isolated human colon preserved at 4°C for 3, 6 or 9 hours increased up to 90 min and was thereafter constant for at least 40 min. The permeability of FD-4, a paracellular permeable compound, was restricted at constant Rm. On the other hand, the value of potential difference and of short circuit current as well as that of Rm was constant for at least 40 min. Neither preservation for 12 hours at 4°C nor that for 3 hours at room temperature was suitable when evaluated in terms of the recovery of Rm. These results indicate that cell viability was guaranteed for 9 hours provided that isolated human colon tissues were preserved at 4°C. Furthermore, it is necessary to preincubate for at least 90 min to obtain a structural and functional recovery of the paracellular and transcellular route.