Document Detail


Inhibition of active sodium transport by cytochalasin B in rat jejunum in vitro.
MedLine Citation:
PMID:  6307390     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The effects of cytochalasin B on electrophysiological properties and sodium transport in rat jejunum in vitro are described. Stripped paired rat jejunal segments were maintained in Ussing chambers with Leibovitz's (L-15) tissue culture medium bubbled with 100% oxygen. L-15 medium contains galactose as the only sugar, and an assortment of amino acids and cofactors to nourish the tissue. Electrophysiological parameters of short-circuit current (Isc) and transepithelial potential difference could be maintained for up to 4 h in control tissues. Upon application of cytochalasin B (20 micrograms/ml), on the mucosal side, Isc and potential difference fell within 1 h from 1.93 +/- 0.12 to 1.09 +/- 0.14 (mean +/- S.E.) muequiv./cm2 per h and from 5 to 2.5 mV. Tissue resistance remained unchanged at approx. 110 omega X cm2 for up to 4 h. 22Na net flux was 4.1 +/- 0.9 muequiv./cm2 per h during the last control period and fell to zero within 1 h after cytochalasin B treatment. Transmission electron micrographs revealed no gross morphological changes at this dose. Absorptive junctional morphology was apparently not altered by cytochalasin B treatment, a finding which was consistent with the stable transepithelial electrical resistance observed during exposure to this drug. Active sodium transport processes coupled to hexose, amino acid, and chloride movements are all possible in L-15 medium. However, following exposure to 20 micrograms/ml cytochalasin B, all net sodium transport is completely inhibited. The data are consistent with the hypothesis of a common regulator for active sodium transport processes which is modulated through structural changes in cytoskeletal organization.
Authors:
P T Beall; K J Karnaky; L T Garretson; Y J Kuo; L L Shanbour
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Biochimica et biophysica acta     Volume:  763     ISSN:  0006-3002     ISO Abbreviation:  Biochim. Biophys. Acta     Publication Date:  1983 Aug 
Date Detail:
Created Date:  1983-09-23     Completed Date:  1983-09-23     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  0217513     Medline TA:  Biochim Biophys Acta     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  19-26     Citation Subset:  IM    
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MeSH Terms
Descriptor/Qualifier:
Animals
Biological Transport, Active / drug effects
Cytochalasin B / pharmacology*
Dimethyl Sulfoxide / pharmacology
Epithelium / ultrastructure
Intestinal Mucosa / drug effects,  physiology*,  ultrastructure
Jejunum / drug effects,  physiology*
Male
Membrane Potentials / drug effects
Microscopy, Electron
Rats
Rats, Inbred Strains
Sodium / metabolism*
Sodium-Potassium-Exchanging ATPase / metabolism
Grant Support
ID/Acronym/Agency:
AA00194-10/AA/NIAAA NIH HHS; GM29099/GM/NIGMS NIH HHS
Chemical
Reg. No./Substance:
14930-96-2/Cytochalasin B; 67-68-5/Dimethyl Sulfoxide; 7440-23-5/Sodium; EC 3.6.3.9/Sodium-Potassium-Exchanging ATPase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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