The goal of the project is to determine whether juxtamedullary nephrons of the kidney exhibit the ability to exert feedback control on their rate of glomerular filtration. In a series of open-feedback-loop experiments, tubuloglomerular feedback will be measured in juxtamedullary and superficial nephrons in hydropenic and diuretic hamster kidneys. The effects of Henle's loop perfusion rate and perfusate composition on filtration rate in the same nephron will be measured. In a series of closed-feedback-loop experiments, it will be determined whether tubuloglomerular feedback mediates juxtamedullary nephron autoregulation of glomerular filtration rate. By measuring juxtamedullary nephron filtration rate without interrupting the mechanism of tubuloglomerular feedback during diuresis, it will be determined if the increased loop of Henle flow due to the diuresis leads to a reduction in single nephron filtration rate by activating juxtamedullary nephron tubuloglomerular feedback. An integral part of the research is a mathematical model of Henle's loop function. The model, which stimulates loop water and solute reabsorption, is used for experimental design and data interpretation.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK026341-07
Application #
3227839
Study Section
General Medicine B Study Section (GMB)
Project Start
1979-12-01
Project End
1987-11-30
Budget Start
1985-12-01
Budget End
1986-11-30
Support Year
7
Fiscal Year
1986
Total Cost
Indirect Cost
Name
State University New York Stony Brook
Department
Type
Schools of Medicine
DUNS #
804878247
City
Stony Brook
State
NY
Country
United States
Zip Code
11794
Goligorsky, M S; Iijima, K; Krivenko, Y et al. (1997) Role of mesangial cells in macula densa to afferent arteriole information transfer. Clin Exp Pharmacol Physiol 24:527-31
Casellas, D; Bouriquet, N; Moore, L C (1997) Branching patterns and autoregulatory responses of juxtamedullary afferent arterioles. Am J Physiol 272:F416-21
Norling, L L; Tufro-McReddie, A; Ariel Gomez, R et al. (1996) Accumulation of acidic renin isoforms in kidneys of cyclosporine-A-treated rats. J Am Soc Nephrol 7:331-7
Goligorsky, M S; Colflesh, D; Gordienko, D et al. (1995) Branching points of renal resistance arteries are enriched in L-type calcium channels and initiate vasoconstriction. Am J Physiol 268:F251-7
Layton, H E; Pitman, E B; Moore, L C (1995) Instantaneous and steady-state gains in the tubuloglomerular feedback system. Am J Physiol 268:F163-74
Tsukahara, H; Krivenko, Y; Moore, L C et al. (1994) Decrease in ambient [Cl-] stimulates nitric oxide release from cultured rat mesangial cells. Am J Physiol 267:F190-5
Casellas, D; Dupont, M; Bouriquet, N et al. (1994) Anatomic pairing of afferent arterioles and renin cell distribution in rat kidneys. Am J Physiol 267:F931-6
Pitman, E B; Layton, H E; Moore, L C (1994) Numerical simulation of propagating concentration profiles in renal tubules. Bull Math Biol 56:567-86
Moore, L C; Rich, A; Casellas, D (1994) Ascending myogenic autoregulation: interactions between tubuloglomerular feedback and myogenic mechanisms. Bull Math Biol 56:391-410
Casellas, D; Dupont, M; Kaskel, F J et al. (1993) Direct visualization of renin-cell distribution in preglomerular vascular trees dissected from rat kidney. Am J Physiol 265:F151-6

Showing the most recent 10 out of 23 publications