+1 Recommend
0 collections
      • Record: found
      • Abstract: found
      • Article: not found

      Enhanced large intestinal potassium permeability in end-stage renal disease.

      The Journal of Pathology

      secretion, Statistics, Nonparametric, pharmacology, Case-Control Studies, Cations, Dialysis, Female, Barium, Humans, Immunohistochemistry, methods, Intestinal Mucosa, Intestine, Large, metabolism, Kidney Failure, Chronic, physiopathology, Male, Middle Aged, Permeability, Potassium, Potassium Channel Blockers, Potassium Channels, analysis, Rectum, Adult, Aged

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          The capacity of the colon for potassium (K+) secretion increases in end-stage renal disease (ESRD), to the extent that it makes a substantial contribution to K+ homeostasis. This colonic K+ adaptive response may reflect enhanced active K+ secretion, and be associated with an increase in apical membrane K+ permeability. In this study, this hypothesis was tested in patients with normal renal function or ESRD, by evaluating the effect of barium ions (a K+ channel inhibitor) on rectal K+ secretion using a rectal dialysis technique, and the expression of high conductance (BK) K+ channel protein in colonic mucosa by immunohistochemistry. Under basal conditions, rectal K+ secretion was almost threefold greater (p < 0.02) in ESRD patients (n = 8) than in patients with normal renal function (n = 10). Intraluminal barium (5 mmol/l) decreased K+ secretion in the ESRD patients by 45% (p < 0.05), but had no effect on K+ transport in patients with normal renal function. Immunostaining using a specific antibody to the BK channel alpha-subunit revealed greater (p < 0.001) levels of BK channel protein expression in surface colonocytes and crypt cells in ESRD patients (n = 9) than in patients with normal renal function (n = 9), in whom low levels of expression were mainly restricted to surface colonocytes. In conclusion, these results suggest that enhanced colonic K+ secretion in ESRD involves an increase in the apical K+ permeability of the large intestinal epithelium, which most likely reflects increased expression of apical BK channels. 2005 Pathological Society of Great Britain and Ireland

          Related collections

          Author and article information



          Comment on this article