Document Detail

Effect of osmotic swelling on K+ conductance in jejunal crypt epithelial cells.
MedLine Citation:
PMID:  1377449     Owner:  NLM     Status:  MEDLINE    
To further elucidate differences in ion transport properties between jejunal crypt and villus cells, we compared the responses of purified cell suspensions to hypotonic stress using electronic cell sizing to evaluate volume changes and 86Rb and 36Cl efflux. After hypotonic swelling, villus enterocytes undergo a regulatory volume decrease (RVD) due to the loss of K+ and Cl- through volume-activated conductances. After 0.6x isotonic challenge in Na(+)-free medium, crypt cells exhibited only partial RVD, with t1/2 congruent to 15 min. The addition of a cation ionophore, gramicidin (0.25 microM), to hypotonically swollen crypt cells caused an accelerated RVD, which was complete with t1/2 congruent to 5 min. Crypt epithelial cells showed no volume-activated 86Rb efflux, but villus enterocytes had an increased rate of 86Rb efflux after hypotonic dilution (P less than 0.001). Gramicidin added to hypotonically diluted crypt cells greatly increased the rate of 86Rb efflux compared with controls. Both villus (30 s; P less than 0.005) and crypt (2 min; P less than 0.001) cells exhibited volume-activated 36Cl efflux in absence of gramicidin. Cl- channel blockers anthracene-9-carboxylate (9-AC, 300 microM) and indanyloxyacetic acid (IAA-94, 100 microM) prevented crypt RVD (P less than 0.001) in the presence of gramicidin. Ouabain (P less than 0.001) or K(+)-free Na(+)-containing medium, but not Ba2+ (5 mM) or quinine (100 microM), prevented crypt partial RVD. We conclude that crypt cells lack volume-activated K+ conductance. The RVD exhibited by crypt cells, although partial, was due to Cl- loss through a volume-activated Cl- conductance and Na+ loss via Na(+)-K(+)-ATPase.
R J MacLeod; P Lembessis; J R Hamilton
Related Documents :
1336929 - Intracellular ph regulation by a na+/h+ exchanger in cultured bovine trabecular cells.
2764099 - Volume regulation of human lymphocytes by aldosterone in isotonic media.
21200139 - A new regulator of the cell cycle: the pr-set7 histone methyltransferase.
15106949 - Atpases and lens ion balance.
2156449 - Proliferation and intracellular ph in cultured proximal tubular cells.
2918039 - Ionic dependence of the extracellular atp-induced permeabilization of transformed mouse...
15710389 - Small jab1-containing subcomplex is regulated in an anchorage- and cell cycle-dependent...
22469469 - Galpha/lgn-mediated asymmetric spindle positioning does not lead to unequal cleavage of...
9402699 - Developmental biology of biofilms: implications for treatment and control.
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  The American journal of physiology     Volume:  262     ISSN:  0002-9513     ISO Abbreviation:  Am. J. Physiol.     Publication Date:  1992 Jun 
Date Detail:
Created Date:  1992-07-29     Completed Date:  1992-07-29     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370511     Medline TA:  Am J Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  G1021-6     Citation Subset:  IM    
Department of Pediatrics, McGill University-Montreal Children's Hospital Research Institute, Quebec, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Chloride Channels
Chlorides / metabolism
Epithelium / drug effects,  physiology
Guinea Pigs
Hypotonic Solutions
Ion Channels / physiology
Jejunum / physiology*
Membrane Proteins / physiology
Microvilli / enzymology,  physiology
Ouabain / pharmacology
Potassium Channels / physiology*
Quinine / pharmacology
Rubidium / metabolism,  pharmacology
Reg. No./Substance:
0/Chloride Channels; 0/Chlorides; 0/Hypotonic Solutions; 0/Ion Channels; 0/Membrane Proteins; 0/Potassium Channels; 130-95-0/Quinine; 630-60-4/Ouabain; 7440-17-7/Rubidium

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

Previous Document:  Regulation of alpha 1-beta 3-NA(+)-K(+)-ATPase isozyme during meiotic maturation of Xenopus laevis o...
Next Document:  Anion channels in rat liver canalicular plasma membranes reconstituted into planar lipid bilayers.