title: Segmental differences in K-transport across rabbit proximal and distal colon in vivo and in vitro.
abstract: Net K-transport was investigated in three different segments of rabbit proximal and distal colon. In vivo studies used a dialysis method, and in vitro studies an everted sac preparation. Results from both methods are in good agreement and show net K-absorption in the two segments of the proximal colon, and net K-secretion in the distal colon. K-absorption in the proximal colon seems to be an active mechanism, because K is transported against an electrical potential gradient. The present study is a comparative approach to demonstrate the heterogeneity of an organ function, and represents the first direct comparison of K-transport in various segments of rabbit colon under in vitro and in vivo conditions.
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D003106:Colon / Q000378:metabolism*; D007408:Intestinal Absorption; D007700:Kinetics; D009928:Organ Specificity; D011188:Potassium / Q000378:metabolism*; D011817:Rabbits
chemical_list: D011188:Potassium