The major goal of this work is to determine how the acid-secreting parietal cells of the rabbit stomach maintain ionic homeostasis during large changes in their secretory activity. Microspectrofluorimetry and digital image processing of pH-, Na- Ca-, Cl- and K-sensitive fluorescent dyes will be used to determine how the ion exchangers (Na/H, Cl/HCO3, and Na/Ca), cotransporter (Na/HCO3), ATP-ases (Na/K and H/K), and Ca """"""""channels"""""""" are controlled by the H2 agonist histamine and muscarinic agonist carbachol. The roles which different second messengers like Ca, pH, CAMP and protein kinase C may play in stimulus secretion coupling will also be investigated, as will the roles which Na/H and Cl/HC03 exchange might play in maintenance of the """"""""barrier"""""""" function of the enzyme-secreting chief cells and mucus-secreting surface epithelial cells. These data will be of importance in knowing how stomach cells operate in healthy and diseased states. Also, since the membrane transport processes and stimulus-secretion coupling mechanisms are present in most secretory cells, the work should have quite broad relevance.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK019520-16
Application #
2137338
Study Section
Physiology Study Section (PHY)
Project Start
1977-04-01
Project End
1995-11-30
Budget Start
1993-12-01
Budget End
1995-11-30
Support Year
16
Fiscal Year
1994
Total Cost
Indirect Cost
Name
University of California Berkeley
Department
Physiology
Type
Schools of Arts and Sciences
DUNS #
094878337
City
Berkeley
State
CA
Country
United States
Zip Code
94704
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Poulsen, J H; Fischer, H; Illek, B et al. (1994) Bicarbonate conductance and pH regulatory capability of cystic fibrosis transmembrane conductance regulator. Proc Natl Acad Sci U S A 91:5340-4

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