Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-19801
J Membr Biol 1995 May 01;1452:193-204. doi: 10.1007/bf00237377.
Show Gene links Show Anatomy links

Cytoskeletal disruption in A6 kidney cells: impact on endo/exocytosis and NaCl transport regulation by antidiuretic hormone.

Verrey F , Groscurth P , Bolliger U .


???displayArticle.abstract???
Antidiuretic hormone (ADH; 2.5 x 10(-8) M vasotocin) produces a stimulation of apical fluid phase endocytosis, protein secretion and NaCl reabsorption in Xenopus laevis A6 distal nephron cell epithelia pretreated with aldosterone (10(-6) M). The increase of NaCl transport is mediated by a sequential opening of apical Cl and Na conductances. The aim of this study was to characterize the actin and tubulin cytoskeleton of A6 cells and to assess the impact of its disruption on baseline and ADH-induced apical vesicular membrane movements and ion transport to test for possible functional links. The microfilament (MF) and microtubule (MT) networks and their disruption were visualized by confocal laser microscopy. Conditions of depolimerization were selected, by cytochalasin D or cold and nocodazole, respectively. MF disruption produced an increase in baseline apical protein secretion (exocytic movements) (plus 18%) and a decrease of its induction by ADH (minus 35%). MF disruption also increased baseline horseradish peroxidase uptake (endocytic movements) (plus 21%), however, without affecting its ADH-induced increase. In the case of MT disruption, the ADH-induced stimulation of both protein secretion and fluid phase endocytosis was decreased by 70 and 44%, respectively. At the ion transport level, MF and MT disruption only insignificantly affected the ADH-induced Cl conductance, while they decreased the ADH-induced stimulation of Na transport (amiloride-sensitive short-circuit current and conductance) by a factor of 2 to 4. In conclusion, both MT and MF disruption decrease ADH-induced apical protein secretion and Na conductance, while the ADH-induced apical Cl conductance is not significantly affected. Taken together the data support the hypothesis that the modulation of Na channel expression by apical vesicular membrane movements plays a role in Na transport expression and its regulation by ADH.

???displayArticle.pubmedLink??? 7563021
???displayArticle.link??? J Membr Biol


Species referenced: Xenopus laevis
Genes referenced: actl6a

References [+] :
Beron, Aldosterone induces early activation and late accumulation of Na-K-ATPase at surface of A6 cells. 1994, Pubmed, Xenbase