Proinflammatory Cytokines and Potassium Channels in the Kidney.
Proinflammatory cytokines affect several cell functions via receptor-mediated processes. In the kidney, functions of transporters and ion channels along the nephron are also affected by some cytokines. Among these, alteration of activity of potassium ion (K(+)) channels induces changes in transepithelial transport of solutes and water in the kidney, since K(+) channels in tubule cells are indispensable for formation of membrane potential which serves as a driving force for the transepithelial transport. Altered K(+) channel activity may be involved in renal cell dysfunction during inflammation. Although little information was available regarding the effects of proinflammatory cytokines on renal K(+) channels, reports have emerged during the last decade. In human proximal tubule cells, interferon-γ showed a time-dependent biphasic effect on a 40 pS K(+) channel, that is, delayed suppression and acute stimulation, and interleukin-1β acutely suppressed the channel activity. Transforming growth factor-β1 activated KCa3.1 K(+) channel in immortalized human proximal tubule cells, which would be involved in the pathogenesis of renal fibrosis. This review discusses the effects of proinflammatory cytokines on renal K(+) channels and the causal relationship between the cytokine-induced changes in K(+) channel activity and renal dysfunction.
Department of Physiology, Iwate Medical University School of Medicine, 2-1-1 Nishitokuta, Yahaba, Iwate 028-3694, Japan.
Kazuyoshi
K
Nakamura
Department of Physiology, Iwate Medical University School of Medicine, 2-1-1 Nishitokuta, Yahaba, Iwate 028-3694, Japan.
Hikaru
H
Hayashi
Department of Physiology, Iwate Medical University School of Medicine, 2-1-1 Nishitokuta, Yahaba, Iwate 028-3694, Japan.
Manabu
M
Kubokawa
D000818:Animals; D001692:Biological Transport; D016207:Cytokines / Q000378:metabolism*; D005355:Fibrosis / Q000473:pathology; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D007684:Kidney Tubules / Q000378:metabolism; D051379:Mice; D011188:Potassium / Q000737:chemistry; D015221:Potassium Channels / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism
D016207:Cytokines; D015221:Potassium Channels; D053773:Transforming Growth Factor beta1; D011188:Potassium