The kallikrein-kinin system of the kidney is thought to influence renal hemodynamics, water and electrolyte excretion. The mechanisms which control this system are uncertain. Microperfusion techniques will be used in the rat to study the site, rate and control of kallikrein secretion in the renal tubule. Kallikrein will be measured by a new microkininogenase assay and, if possible, by a direct kallikrein immunoassay of increased sensitivity under development.
Specific aims are as follows. 1. Locate the nephron site or sites at which kallikrein is secreted into the urine and quantify the rate of secretion. 2. Evaluate the effect of changes in urine flow and electrolyte concentrations on the rate of kallikrein secretion. 3. Determine whether the reported effects of changes in renal hemodynamics (renal blood flow, arterial and venous pressure) on kallikrein excretion are direct or secondary to changes in urine flow and composition. 4. Study the effects of hormones (mineralocorticoids, prostaglandins, angiotensin) on tubular secretion of kallikrein. 5. Evaluate the influence of diuretics and vasodilators on tubular kallikrein secretion when urine flow and composition are held constant. 6. Determine whether the kallikrein-kinin system influences distal tubular water and electrolyte transport. In addition, efforts will be made to develop an ultrasensitive kinin assay, in which case similar microperfusion studies of the locus, rate and control of kinin formation in the tubule will become possible. These studies should increase knowledge of a hormonal system which influences kidney function and may play a role in hypertension.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL031417-05
Application #
3342516
Study Section
Cardiovascular and Pulmonary Research B Study Section (CVB)
Project Start
1983-12-01
Project End
1989-11-30
Budget Start
1987-12-01
Budget End
1989-11-30
Support Year
5
Fiscal Year
1988
Total Cost
Indirect Cost
Name
Boston University
Department
Type
DUNS #
City
Boston
State
MA
Country
United States
Zip Code
02118
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Lieberthal, W; Vasilevsky, M L; Valeri, C R et al. (1987) Interactions between ADH and prostaglandins in isolated erythrocyte-perfused rat kidney. Am J Physiol 252:F331-7

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