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. 1990 Feb;85(2):340–344. doi: 10.1172/JCI114443

Intracellular cystine loading inhibits transport in the rabbit proximal convoluted tubule.

R F Salmon 1, M Baum 1
PMCID: PMC296429  PMID: 2298908

Abstract

Cystinosis is an autosomal recessive disorder characterized by a high intracellular cystine concentration. To establish an in vitro model of this disorder and examine the mechanism of the proximal tubule transport defect seen with elevated intracellular cystine concentrations, rabbit proximal convoluted tubules (PCT) were perfused in vitro. PCTs were loaded with cystine using cystine dimethyl ester, a permeative methyl ester derivative. Bath cystine dimethyl ester (0.5 mM) reduced volume absorption (Jv) (0.67 +/- 0.07 to 0.15 +/- 0.09 nl/mm.min, P less than 0.01), bicarbonate transport (JTCO2) (47.2 +/- 4.9 to 11.1 +/- 2.8 pmol/mm.min, P less than 0.001) and glucose transport (JGLU) (34.1 +/- 1.5 to 19.7 +/- 1.5 pmol/mm.min, P less than 0.001). The methyl esters of leucine (0.5 mM), and tryptophan (0.5 and 2.0 mM) had no effect on these parameters. To examine if intracellular reduction of cystine to cysteine could contribute to the inhibition in transport, the effect of bath cysteine methyl ester on proximal tubular transport was examined. Bath cysteine methyl ester (2 but not 0.5 mM) resulted in an inhibition in Jv, JGLU, and JTCO2. Cystine dimethyl ester had no effect on mannitol or bicarbonate permeability. These data are consistent with intracellular proximal tubular cystine accumulation resulting in an inhibition of active transport.

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Selected References

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  1. Baum M. Insulin stimulates volume absorption in the rabbit proximal convoluted tubule. J Clin Invest. 1987 Apr;79(4):1104–1109. doi: 10.1172/JCI112925. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Berry C. A., Cogan M. G. Influence of peritubular protein on solute absorption in the rabbit proximal tubule. A specific effect on NaCl transport. J Clin Invest. 1981 Aug;68(2):506–516. doi: 10.1172/JCI110282. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Burg M., Grantham J., Abramow M., Orloff J. Preparation and study of fragments of single rabbit nephrons. Am J Physiol. 1966 Jun;210(6):1293–1298. doi: 10.1152/ajplegacy.1966.210.6.1293. [DOI] [PubMed] [Google Scholar]
  4. Foreman J. W., Bowring M. A., Lee J., States B., Segal S. Effect of cystine dimethylester on renal solute handling and isolated renal tubule transport in the rat: a new model of the Fanconi syndrome. Metabolism. 1987 Dec;36(12):1185–1191. doi: 10.1016/0026-0495(87)90246-0. [DOI] [PubMed] [Google Scholar]
  5. Gahl W. A., Bashan N., Tietze F., Bernardini I., Schulman J. D. Cystine transport is defective in isolated leukocyte lysosomes from patients with cystinosis. Science. 1982 Sep 24;217(4566):1263–1265. doi: 10.1126/science.7112129. [DOI] [PubMed] [Google Scholar]
  6. Gahl W. A. Cystinosis coming of age. Adv Pediatr. 1986;33:95–126. [PubMed] [Google Scholar]
  7. Gahl W. A., Tietze F., Bashan N., Bernardini I., Raiford D., Schulman J. D. Characteristics of cystine counter-transport in normal and cystinotic lysosome-rich leucocyte granular fractions. Biochem J. 1983 Nov 15;216(2):393–400. doi: 10.1042/bj2160393. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Gahl W. A., Tietze F., Bashan N., Steinherz R., Schulman J. D. Defective cystine exodus from isolated lysosome-rich fractions of cystinotic leucocytes. J Biol Chem. 1982 Aug 25;257(16):9570–9575. [PubMed] [Google Scholar]
  9. Goldman R., Kaplan A. Rupture of rat liver lysosomes mediated by L-amino acid esters. Biochim Biophys Acta. 1973 Aug 22;318(2):205–216. doi: 10.1016/0005-2736(73)90114-4. [DOI] [PubMed] [Google Scholar]
  10. Patrick A. D., Lake B. D. Cystinosis: electron microscopic evidence of lysosomal storage of cystine in lymph node. J Clin Pathol. 1968 Sep;21(5):571–575. doi: 10.1136/jcp.21.5.571. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Preisig P. A., Berry C. A. Evidence for transcellular osmotic water flow in rat proximal tubules. Am J Physiol. 1985 Jul;249(1 Pt 2):F124–F131. doi: 10.1152/ajprenal.1985.249.1.F124. [DOI] [PubMed] [Google Scholar]
  12. Reeves J. P. Accumulation of amino acids by lysosomes incubated with amino acid methyl esters. J Biol Chem. 1979 Sep 25;254(18):8914–8921. [PubMed] [Google Scholar]
  13. Sasaki S., Berry C. A., Rector F. C., Jr Effect of luminal and peritubular HCO3(-) concentrations and PCO2 on HCO3(-) reabsorption in rabbit proximal convoluted tubules perfused in vitro. J Clin Invest. 1982 Sep;70(3):639–649. doi: 10.1172/JCI110658. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Schneider J. A., Bradley K., Seegmiller J. E. Increased cystine in leukocytes from individuals homozygous and heterozygous for cystinosis. Science. 1967 Sep 15;157(3794):1321–1322. doi: 10.1126/science.157.3794.1321. [DOI] [PubMed] [Google Scholar]
  15. Schneider J. A., Rosenbloom F. M., Bradley K. H., Seegmiller J. E. Increased free-cystine content of fibroblasts cultured from patients with cystinosis. Biochem Biophys Res Commun. 1967 Nov 30;29(4):527–531. doi: 10.1016/0006-291x(67)90516-5. [DOI] [PubMed] [Google Scholar]
  16. Schulman J. D., Bradley K. H. The metabolism of amino acids, peptides, and disulfides in lysosomes of fibroblasts cultured from normal individuals and those with cystinosis. J Exp Med. 1970 Dec 1;132(6):1090–1104. doi: 10.1084/jem.132.6.1090. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Steinherz R., Tietze F., Gahl W. A., Triche T. J., Chiang H., Modesti A., Schulman J. D. Cystine accumulation and clearance by normal and cystinotic leukocytes exposed to cystine dimethyl ester. Proc Natl Acad Sci U S A. 1982 Jul;79(14):4446–4450. doi: 10.1073/pnas.79.14.4446. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Vurek G. G., Warnock D. G., Corsey R. Measurement of picomole amounts of carbon dioxide by calorimetry. Anal Chem. 1975 Apr;47(4):765–767. doi: 10.1021/ac60354a024. [DOI] [PubMed] [Google Scholar]

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