The objective of this proposal is a comprehensive investigation leading to an understanding of those inherited metabolic diseases which have been called disorders of transport. The underlying approach continues to be the application of biochemical techniques to delinate the basic derangements of cellular function resulting from genetic abnormality phenotypically expressed as aminoaciduria, mellituria, and uricosuria. Various model systems ranging from the intact animals to isolated membranes will be employed. Those aspects to be examined are: 1) the basic molecular abnormality underlying human cystinuria by a multifaceted approach which characterizes cystine and dibasic amino acid transport in isolated intestinal and renal membranes and which examines physiological handling of these amino acids in intact cystinuric animals, the dog and the maned wolf; 2) developmental characteristics of amino acid, sugar, and urate transport, focusing on regulation and control; 3) the underlying defect responsible for the global dysfunction of transport called the Fanconi syndrome by utilizing the affected Basenji dog as a model; 4) the mechanisms of urate transport in isolated renal membranes with regard to the Fanconi syndrome, the Dalmatian dog syndrome, and hyperuricemia in man, and 5) the relation of membrane structure and function by dissembling the renal brushborder, analyzing its components and their contribution to the transport process, and then reconstituting the transport system by incorporating components into artificial proteoliposomes.

Project Start
1974-09-01
Project End
1987-08-31
Budget Start
1985-09-01
Budget End
1986-08-31
Support Year
20
Fiscal Year
1985
Total Cost
Indirect Cost
Name
Children's Hospital of Philadelphia
Department
Type
DUNS #
073757627
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
McNamara, P D; Rea, C T; Bovee, K C et al. (1989) Cystinuria in dogs: comparison of the cystinuric component of the Fanconi syndrome in basenji dogs to isolated cystinuria. Metabolism 38:8-15
Foreman, J W; Lee, J; Segal, S (1988) Characteristics of cystine uptake by cultured LLC-PK1 cells. Biochim Biophys Acta 968:323-30
Medow, M S; Segal, S (1987) Age related changes in fluidity of rat renal brushborder membrane vesicles. Biochem Biophys Res Commun 142:849-56
Bowring, M A; Foreman, J W; Lee, J et al. (1987) Characteristics of lysine transport by isolated rat renal cortical tubule fragments. Biochim Biophys Acta 901:23-9
Foreman, J W; Bowring, M A; Lee, J et al. (1987) Effect of cystine dimethylester on renal solute handling and isolated renal tubule transport in the rat: a new model of the Fanconi syndrome. Metabolism 36:1185-91
States, B; Foreman, J W; Segal, S (1987) Cysteine and glutathione levels in developing rat kidney and liver. Pediatr Res 22:605-8
States, B; Foreman, J; Lee, J et al. (1987) Cystine and lysine transport in cultured human renal epithelial cells. Metabolism 36:356-62
Nissim, I; States, B; Yudkoff, M et al. (1987) Characterization of amino acid metabolism by cultured rat kidney cells: study with 15N. Am J Physiol 253:F1243-52
Hsu, B Y; Corcoran, S M; Segal, S (1986) L-cystine transport by papain-treated rat renal brush-border membrane vesicles. Biochim Biophys Acta 859:79-87
Hsu, B Y; McNamara, P D; Rea, C T et al. (1986) Assessment of binding of L-cystine and L-lysine by rat renal brush-border membranes. Biochim Biophys Acta 863:332-6

Showing the most recent 10 out of 16 publications