The proposed studies aim to characterize the regulation of urinary buffer excretion particularly as it relates to acid-base homeostasis. In this regard the mechanism and regulation of ammonia transport in the kidney will be examined. In addition, various factors which may alter intracellular pH and lumen pH in acid-base disorders will be examined. pH in these various compartments may have a significant impact on urinary buffer excretion and hence on acid-base homeostasis. The various regulatory factors to be studied in both the regulation of ammonia excretion and intracellular and luminal pH are those factors which are important in acid-base disorders and other physiologically relevant circumstances. Regulation of urinary citrate excretion will also be examined since citrate metabolism and transport are altered significantly by acid-base disturbances. Urinary citrate is principally important clinically as an endogenous inhibitor of calcium nephrolithiasis. Therefore, these findings may have direct relevance to certain conditions causing nephrolithiasis and to measures to prevent calcium nephrolithiasis. All of the proposed studies will use in vitro studies of perfused rabbit nephron segments. Standard method of measurement of transport rates will be utilized. Intracellular and lumen pH will be measured using recently described fluorescent markers.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
2R01DK034394-04
Application #
3232719
Study Section
General Medicine B Study Section (GMB)
Project Start
1984-07-01
Project End
1992-06-30
Budget Start
1987-07-01
Budget End
1988-06-30
Support Year
4
Fiscal Year
1987
Total Cost
Indirect Cost
Name
Washington University
Department
Type
Schools of Medicine
DUNS #
062761671
City
Saint Louis
State
MO
Country
United States
Zip Code
63130