Regulation of epithelial sodium transport via epithelial Na+ channel.
Renal epithelial Na+ transport plays an important role in homeostasis of our body fluid content and blood pressure. Further, the Na+ transport in alveolar epithelial cells essentially controls the amount of alveolar fluid that should be kept at an appropriate level for normal gas exchange. The epithelial Na+ transport is generally mediated through two steps: (1) the entry step of Na+ via epithelial Na+ channel (ENaC) at the apical membrane and (2) the extrusion step of Na+ via the Na+, K+-ATPase at the basolateral membrane. In general, the Na+ entry via ENaC is the rate-limiting step. Therefore, the regulation of ENaC plays an essential role in control of blood pressure and normal gas exchange. In this paper, we discuss two major factors in ENaC regulation: (1) activity of individual ENaC and (2) number of ENaC located at the apical membrane.
Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan. marunaka@koto.kpu-m.ac.jp
Yoshinori
Y
Marunaka
Naomi
N
Niisato
Akiyuki
A
Taruno
Mariko
M
Ohta
Hiroaki
H
Miyazaki
Shigekuni
S
Hosogi
Ken-Ichi
K
Nakajima
Katsuyuki
K
Kusuzaki
Eishi
E
Ashihara
Kyosuke
K
Nishio
Yoshinobu
Y
Iwasaki
Takashi
T
Nakahari
Takahiro
T
Kubota
D000818:Animals; D004847:Epithelial Cells / Q000378:metabolism*; D053503:Epithelial Sodium Channels / Q000378:metabolism*; D006801:Humans; D017136:Ion Transport; D051379:Mice; D012964:Sodium / Q000378:metabolism*
D053503:Epithelial Sodium Channels; D012964:Sodium