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PubMed · 1899002

Vasopressin depolymerizes F-actin in toad bladder epithelial cells.

G H Ding·N Franki·J Condeelis·R M Hays
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Abstract

Vasopressin (AVP) induces the rapid fusion of water channel-containing vesicles with the luminal membrane of its target cell. We have carried out a quantitative study of the F-actin content of toad bladder epithelial cells, using the rhodamine phalloidin binding assay. As early as 1 min after AVP stimulation, there is a significant 15% reduction of cellular F-actin, which remains reduced by 20-30% for the duration of action of AVP. Comparable reductions were seen following 8-bromoadenosine 3',5'-cyclic monophosphate, 1-desamino-8-D-arginine vasopressin, and forskolin. F-actin content rose to and then exceeded that of control bladders after AVP washout. Inhibition of prostaglandin synthesis enhanced both water flow and the decrease of F-actin. In the living cell, stabilization of F-actin with NBD-phallacidin selectively inhibited water flow. In view of the rapidity of the response, we conclude that AVP shifts the equilibrium between F-actin and G-actin monomers, and this depolymerization may be required for vesicle fusion.

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8-Bromo Cyclic Adenosine MonophosphateActinsAmanitinsAnimalsArginine VasopressinBufo marinusDeamino Arginine VasopressinEpitheliumFemaleIn Vitro TechniquesMacromolecular SubstancesMicroscopy, ElectronRana catesbeianaUrinary BladderJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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G H Ding, N Franki, J Condeelis, R M Hays. 1991. Vasopressin depolymerizes F-actin in toad bladder epithelial cells.. https://doi.org/10.1152/ajpcell.1991.260.1.c9

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