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Wiriyasermkul P, Moriyama S, Suzuki M, Kongpracha P, Nakamae N, Takeshita S, Tanaka Y, Matsuda A, Miyasaka M, Hamase K, Kimura T, Mita M, Sasabe J, Nagamori S. <sc>A</sc> multi-hierarchical approach reveals <sc>d</sc>-serine as a hidden substrate of sodium-coupled monocarboxylate transporters. eLife 2024; 12:RP92615. [PMID: 38650461 PMCID: PMC11037918 DOI: 10.7554/elife.92615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
Transporter research primarily relies on the canonical substrates of well-established transporters. This approach has limitations when studying transporters for the low-abundant micromolecules, such as micronutrients, and may not reveal physiological functions of the transporters. While d-serine, a trace enantiomer of serine in the circulation, was discovered as an emerging biomarker of kidney function, its transport mechanisms in the periphery remain unknown. Here, using a multi-hierarchical approach from body fluids to molecules, combining multi-omics, cell-free synthetic biochemistry, and ex vivo transport analyses, we have identified two types of renal d-serine transport systems. We revealed that the small amino acid transporter ASCT2 serves as a d-serine transporter previously uncharacterized in the kidney and discovered d-serine as a non-canonical substrate of the sodium-coupled monocarboxylate transporters (SMCTs). These two systems are physiologically complementary, but ASCT2 dominates the role in the pathological condition. Our findings not only shed light on renal d-serine transport, but also clarify the importance of non-canonical substrate transport. This study provides a framework for investigating multiple transport systems of various trace micromolecules under physiological conditions and in multifactorial diseases.
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Affiliation(s)
- Pattama Wiriyasermkul
- Center for SI Medical Research, The Jikei University School of MedicineTokyoJapan
- Department of Laboratory Medicine, The Jikei University School of MedicineTokyoJapan
- Department of Collaborative Research for Biomolecular Dynamics, Nara Medical UniversityNaraJapan
| | - Satomi Moriyama
- Department of Collaborative Research for Biomolecular Dynamics, Nara Medical UniversityNaraJapan
| | - Masataka Suzuki
- Department of Pharmacology, Keio University School of MedicineTokyoJapan
| | - Pornparn Kongpracha
- Center for SI Medical Research, The Jikei University School of MedicineTokyoJapan
- Department of Laboratory Medicine, The Jikei University School of MedicineTokyoJapan
| | - Nodoka Nakamae
- Department of Collaborative Research for Biomolecular Dynamics, Nara Medical UniversityNaraJapan
| | - Saki Takeshita
- Department of Collaborative Research for Biomolecular Dynamics, Nara Medical UniversityNaraJapan
| | - Yoko Tanaka
- Department of Collaborative Research for Biomolecular Dynamics, Nara Medical UniversityNaraJapan
| | - Akina Matsuda
- Department of Pharmacology, Keio University School of MedicineTokyoJapan
| | - Masaki Miyasaka
- Center for SI Medical Research, The Jikei University School of MedicineTokyoJapan
- Department of Laboratory Medicine, The Jikei University School of MedicineTokyoJapan
| | - Kenji Hamase
- Graduate School of Pharmaceutical Sciences, Kyushu UniversityFukuokaJapan
| | - Tomonori Kimura
- KAGAMI Project, National Institutes of Biomedical Innovation, Health and NutritionOsakaJapan
- Reverse Translational Research Project, Center for Rare Disease Research, National Institutes of Biomedical Innovation, Health and NutritionOsakaJapan
| | | | - Jumpei Sasabe
- Department of Pharmacology, Keio University School of MedicineTokyoJapan
| | - Shushi Nagamori
- Center for SI Medical Research, The Jikei University School of MedicineTokyoJapan
- Department of Laboratory Medicine, The Jikei University School of MedicineTokyoJapan
- Department of Collaborative Research for Biomolecular Dynamics, Nara Medical UniversityNaraJapan
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Kimura T, Sakai S, Isaka Y. D-Serine as a sensor and effector of the kidney. Clin Exp Nephrol 2023; 27:891-900. [PMID: 37498348 PMCID: PMC10582142 DOI: 10.1007/s10157-023-02384-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 07/11/2023] [Indexed: 07/28/2023]
Abstract
D-Serine, a rare enantiomer of serine, is a biomarker of kidney disease and function. The level of D-serine in the human body is precisely regulated through the urinary clearance of the kidney, and its clearance serves as a new measure of glomerular filtration rate with a lower bias than creatinine clearance. D-Serine also has a direct effect on the kidneys and mediates the cellular proliferation of tubular cells via mTOR signaling and induces kidney remodeling as a compensatory reaction to the loss of kidney mass. In living kidney donors, the removal of the kidney results in an increase in blood D-serine level, which in turn accelerates kidney remodeling and augments kidney clearance, thus reducing blood levels of D-serine. This feedback system strictly controls D-serine levels in the body. The function of D-serine as a biomarker and modulator of kidney function will be the basis of precision medicine for kidney diseases.
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Affiliation(s)
- Tomonori Kimura
- Reverse Translational Research Project, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Saito-Asagi 7-6-8, Ibaraki, Osaka, 5670085, Japan.
- KAGAMI Project, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Saito-Asagi 7-6-8, Ibaraki, Osaka, 5670085, Japan.
- Department of Nephrology, Osaka University Graduate School of Medicine, Yamada-oka 2-2, Suita, Osaka, 5650871, Japan.
| | - Shinsuke Sakai
- Reverse Translational Research Project, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Saito-Asagi 7-6-8, Ibaraki, Osaka, 5670085, Japan
- KAGAMI Project, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Saito-Asagi 7-6-8, Ibaraki, Osaka, 5670085, Japan
- Department of Nephrology, Osaka University Graduate School of Medicine, Yamada-oka 2-2, Suita, Osaka, 5650871, Japan
| | - Yoshitaka Isaka
- Department of Nephrology, Osaka University Graduate School of Medicine, Yamada-oka 2-2, Suita, Osaka, 5650871, Japan.
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Hesaka A, Tsukamoto Y, Nada S, Kawamura M, Ichimaru N, Sakai S, Nakane M, Mita M, Okuzaki D, Okada M, Isaka Y, Kimura T. d-Serine Mediates Cellular Proliferation for Kidney Remodeling. KIDNEY360 2021; 2:1611-1624. [PMID: 35372967 PMCID: PMC8785787 DOI: 10.34067/kid.0000832021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 08/16/2021] [Indexed: 02/04/2023]
Abstract
Background d-serine, a long-term undetected enantiomer of serine, is a biomarker that reflects kidney function and disease activity. The physiologic functions of d-serine are unclear. Methods The dynamics of d-serine were assessed by measuring d-serine in human samples of living kidney donors using two-dimensional high-performance liquid chromatography, and by autoradiographic studies in mice. The effects of d-serine on the kidney were examined by gene expression profiling and metabolic studies using unilateral nephrectomy mice, and genetically modified cells. Results Unilateral nephrectomy in human living kidney donors decreases urinary excretion and thus increases the blood level of d-serine. d-serine is quickly and dominantly distributed to the kidney on injection in mice, suggesting the kidney is a main target organ. Treatment of d-serine at a low dose promotes the enlargement of remnant kidney in mouse model. Mechanistically, d-serine activates the cell cycle for tissue remodeling through an mTOR-related pathway. Conclusions d-serine is a physiologic molecule that promotes kidney remodeling. Besides its function as a biomarker, d-serine has a physiologic activity that influences kidney function.
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Affiliation(s)
- Atsushi Hesaka
- KAGAMI Project, National Institutes of Biomedical Innovation, Health and Nutrition,Reverse Translational Project, Center for Rare Disease Research, National Institutes of Biomedical Innovation, Health and Nutrition,Department of Nephrology, Osaka University Graduate School of Medicine
| | - Yusuke Tsukamoto
- KAGAMI Project, National Institutes of Biomedical Innovation, Health and Nutrition,Reverse Translational Project, Center for Rare Disease Research, National Institutes of Biomedical Innovation, Health and Nutrition
| | - Shigeyuki Nada
- Department of Oncogene Research, Research Institute for Microbial Diseases, Osaka University
| | | | - Naotsugu Ichimaru
- Department of Urology, Osaka University Graduate School of Medicine,Department of Advanced Technology for Transplantation, Osaka University Graduate School of Medicine
| | - Shinsuke Sakai
- KAGAMI Project, National Institutes of Biomedical Innovation, Health and Nutrition,Reverse Translational Project, Center for Rare Disease Research, National Institutes of Biomedical Innovation, Health and Nutrition,Department of Nephrology, Osaka University Graduate School of Medicine
| | | | | | - Daisuke Okuzaki
- Genome Information Research Center, Research Institute for Microbial Disease, Osaka University
| | - Masato Okada
- Department of Oncogene Research, Research Institute for Microbial Diseases, Osaka University
| | - Yoshitaka Isaka
- Department of Nephrology, Osaka University Graduate School of Medicine
| | - Tomonori Kimura
- KAGAMI Project, National Institutes of Biomedical Innovation, Health and Nutrition,Reverse Translational Project, Center for Rare Disease Research, National Institutes of Biomedical Innovation, Health and Nutrition,Department of Nephrology, Osaka University Graduate School of Medicine
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Kimura T, Hesaka A, Isaka Y. Utility of d-serine monitoring in kidney disease. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140449. [DOI: 10.1016/j.bbapap.2020.140449] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 05/08/2020] [Accepted: 05/18/2020] [Indexed: 10/24/2022]
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Kimura T, Hesaka A, Isaka Y. D-Amino acids and kidney diseases. Clin Exp Nephrol 2020; 24:404-410. [PMID: 32112266 PMCID: PMC7174270 DOI: 10.1007/s10157-020-01862-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/13/2020] [Indexed: 11/16/2022]
Abstract
d-Amino acids are the recently detected enantiomers of l-amino acids. Accumulating evidence points their potential in solving the long-standing critical problems associated with the management of both chronic and acute kidney diseases. This includes estimating kidney function, early diagnosis and prognosis of chronic kidney disease, and disease monitoring. Among the d-amino acids, d-serine levels in the blood are strongly correlated with the glomerular filtration rate and are useful for estimating the function of the kidney. Urinary d-serine also reflects other conditions. The kidney proximal tubule reabsorbs serine with chiral-selectivity, with d-serine being reabsorbed much less efficiently than l-serine, and urinary excretion of d-serine is sensitive to the presence of kidney diseases. Therefore, assessing the intra-body dynamics of d-serine by measuring its level in blood and urinary excretion can be used to detect kidney diseases and assess pathophysiology. This new concept, the intra-body dynamics of d-serine, can be useful in the comprehensive management of kidney disease.
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Affiliation(s)
- Tomonori Kimura
- KAGAMI Project, National Institute of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan. .,Reverse Translational Research Project, Center for Rare Disease Research, National Institute of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan. .,Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan.
| | - Atsushi Hesaka
- KAGAMI Project, National Institute of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan.,Reverse Translational Research Project, Center for Rare Disease Research, National Institute of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan.,Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yoshitaka Isaka
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
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Abstract
D-Amino acids, long-term undetected enantiomers of L-amino acids, are now emerging as potential biomarkers, especially for kidney diseases. Management of chronic kidney disease (CKD), a global problem with its high prevalence and poor prognosis, is currently unsatisfactory due to the difficulty in estimating kidney function and in early detection of diseases. We now show that intra-body dynamics of D-serine reflect kidney function and diseases. The blood level of D-serine correlated well with the actual glomerular filtration ratio, a key kidney function. This correlation was compatible with those of conventional kidney markers, and blood level of D-serine was relatively unaffected by such clinical factors as body size. The balance between excretion and reabsorption of amino acids by the kidney was controlled with chiral selectivity, and the reabsorption of D-serine was sensitive to the presence of CKD. The combination of blood level and urinary dynamics of D-serine effectively distinguished CKD from non-CKD. These lines of evidence provide new insights into the enantioselective amino acid dynamics in the human body that reflect disease pathophysiology. D-Serine may serve as a vital biomarker that suppress CKD onset through the precise assessment of kidney function and the diagnosis of CKD.
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Distinctive Roles of D-Amino Acids in the Homochiral World: Chirality of Amino Acids Modulates Mammalian Physiology and Pathology. Keio J Med 2018; 68:1-16. [PMID: 29794368 DOI: 10.2302/kjm.2018-0001-ir] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Living organisms enantioselectively employ L-amino acids as the molecular architecture of protein synthesized in the ribosome. Although L-amino acids are dominantly utilized in most biological processes, accumulating evidence points to the distinctive roles of D-amino acids in non-ribosomal physiology. Among the three domains of life, bacteria have the greatest capacity to produce a wide variety of D-amino acids. In contrast, archaea and eukaryotes are thought generally to synthesize only two kinds of D-amino acids: D-serine and D-aspartate. In mammals, D-serine is critical for neurotransmission as an endogenous coagonist of N-methyl D-aspartate receptors. Additionally, D-aspartate is associated with neurogenesis and endocrine systems. Furthermore, recognition of D-amino acids originating in bacteria is linked to systemic and mucosal innate immunity. Among the roles played by D-amino acids in human pathology, the dysfunction of neurotransmission mediated by D-serine is implicated in psychiatric and neurological disorders. Non-enzymatic conversion of L-aspartate or L-serine residues to their D-configurations is involved in age-associated protein degeneration. Moreover, the measurement of plasma or urinary D-/L-serine or D-/L-aspartate levels may have diagnostic or prognostic value in the treatment of kidney diseases. This review aims to summarize current understanding of D-amino-acid-associated biology with a major focus on mammalian physiology and pathology.
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Williams RE, Major H, Lock EA, Lenz EM, Wilson ID. D-Serine-induced nephrotoxicity: a HPLC-TOF/MS-based metabonomics approach. Toxicology 2005; 207:179-90. [PMID: 15596249 DOI: 10.1016/j.tox.2004.08.023] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2004] [Revised: 08/16/2004] [Accepted: 08/16/2004] [Indexed: 11/28/2022]
Abstract
HPLC-MS-based metabonomic analysis was used to investigate urinary metabolic perturbations associated with D-serine-induced nephrotoxicity. D-Serine causes selective necrosis of the proximal straight tubules in the rat kidney accompanied by aminoaciduria, proteinuria and glucosuria. Alderely Park (Wistar-derived) rats were dosed with either D-serine (250 mg/kg ip) or vehicle (deionised water) and urine was collected at 0-12, 12-24, 24-36 and 36-48 h post-dosing. Samples were analysed using a Waters Alliance HT 2795 HPLC system coupled to a Waters Micromass Q-ToF-micro equipped with an electrospray source operating in either positive or negative ion mode. Changes to the urinary profile were detected at all time points compared to control. In negative ion mode, increases were observed in serine (m/z=103.0077), m/z=104.0376 (proposed to be hydroxypyruvate) and glycerate (m/z=105.0215), the latter being metabolites of D-serine. Furthermore, an increase in tryptophan, phenylalanine and lactate and decreases in methylsuccinic acid and sebacic acid were observed. Positive ion analysis revealed a decrease in xanthurenic acid, which has previously been assigned and reported using HPLC-MS following exposure to mercuric chloride and cyclosporine A. A general aminoaciduria, including proline, methionine, leucine, tyrosine and valine was also observed as well as an increase in acetyl carnitine. Investigation of additional metabolites altered as a result of exposure to D-serine is on-going. Thus, HPLC-MS-based metabonomic analysis has provided information concerning the mechanism of D-serine-induced renal injury.
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Affiliation(s)
- R E Williams
- Department of Drug Metabolism and Pharmacokinetics, AstraZeneca, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK
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Williams RE, Lock EA. Sodium benzoate attenuates D-serine induced nephrotoxicity in the rat. Toxicology 2005; 207:35-48. [PMID: 15590120 DOI: 10.1016/j.tox.2004.08.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2004] [Revised: 08/11/2004] [Accepted: 08/13/2004] [Indexed: 11/19/2022]
Abstract
D-Serine causes selective necrosis to the straight portion of the rat renal proximal tubules. The onset is rapid, occurring within 3-4 h and accompanied by proteinuria, glucosuria and aminoaciduria. The metabolism of D-serine by D-amino acid oxidase (D-AAO) may be involved in the mechanism of toxicity. D-AAO is localized within the peroxisomes of renal tubular epithelial cells, which is also the location of D-serine reabsorption. To address the role of D-AAO in D-serine-induced nephrotoxicity, we have examined the effect of sodium benzoate (SB) on the renal injury. SB has been shown to be a potent, competitive inhibitor of kidney D-AAO in vitro. Male Alderley Park rats were exposed to D-serine (500 mg/kg i.p.) 1 h after exposure to SB (125, 250, 500 or 750 mg/kg i.p.). Urine was collected for 0-6 h, then terminal plasma samples and kidneys were taken at 6.5 h. A second group of animals was given SB (500 mg/kg) followed by D-serine (500 mg/kg i.p.; 1 h later) and urine was collected after 0-6, 6-24 and 24-48 h. Terminal plasma samples and kidneys were taken at 48 h. 1H NMR spectroscopic analysis of urine, combined with principal component analysis, demonstrated that SB was able to prevent D-serine-induced perturbations to the urinary profile in a dose dependent manner. This was confirmed by measurement of plasma creatinine and urinary glucose and protein and histopathological examination of the kidneys. Assessment 48 h after D-serine administration revealed that nephrotoxicity was observed in animals pre-treated with SB (500 mg/kg) although the extent of injury was less pronounced than following D-serine alone. These results demonstrate that whilst prior exposure to SB prevents the initial onset of D-serine-induced nephrotoxicity, renal injury is still apparent at later time points. D-AAO activity in the kidney was decreased by 50% 1 h after dosing with SB suggesting that inhibition of this enzyme may be responsible for the observed protection.
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Affiliation(s)
- R E Williams
- Syngenta Central Toxicology Laboratory, Alderley Park, Macclesfield, Cheshire SK10 4TJ, UK
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Silbernagl S, Völker K, Dantzler WH. D-Serine is reabsorbed in rat renal pars recta. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:F857-63. [PMID: 10362774 DOI: 10.1152/ajprenal.1999.276.6.f857] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
D-Serine normally contributes up to 3% to total plasma serine and up to 23% in chronic renal failure. D-Serine is metabolized by tubular D-amino acid oxidase (D-AAO), and high D-serine plasma levels are nephrotoxic; both events are localized in the straight part of the proximal tubule. We therefore investigated if and how D-serine is reabsorbed there. We microinfused 14C-labeled D- or -L-serine + [3H]inulin into early proximal (EP), late proximal (LP), or early distal (ED) tubule sections of superficial nephrons and into long loops of Henle (LLH) of rats in vivo and in situ. The fractional reabsorption (FR) of the 14C label was determined from the 14C:3H ratio in the final urine. At 0.36 mM, FR of D-[14C]serine was 86% (EP), 90% (LP), and approximately 0 (ED, LLH). FR of D-serine could be saturated and inhibited by L-serine (and vice versa). D-methionine, but not D-glutamate or D-arginine, blocked FR of D-serine (LP). We conlude that filtered D-serine is able to enter the pars recta cells, thereby getting access to D-AAO. The uptake carrier has a very low stereospecificity and is, therefore, different from that in the proximal convolution. The colocalization of exclusive reabsorption and metabolism makes the pars recta the tubule site for the recycling of the carbon structure of D-amino acids and, at the same time, the target of D-serine nephrotoxicity.
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Affiliation(s)
- S Silbernagl
- Physiologisches Institut der Universität Würzburg, D-97070 Würzburg, Germany
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Gekle M, Silbernagl S. Basolateral uptake and tubular metabolism of L-citrulline in the isolated-perfused non-filtering kidney of the African clawed toad (Xenopus laevis). Pflugers Arch 1991; 419:492-8. [PMID: 1775371 DOI: 10.1007/bf00370794] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The kidney forms arginine (Arg) by using citrulline (Cit) as precursor, and is the main source of Arg for systemic protein synthesis. Even if the filtered and reabsorbed load (in rats) is sufficient for normal Arg synthesis, the following questions remain. (a) Can Cit be taken up across the contraluminal membrane of the tubule cells also? If so, (b) by what kind of mechanism? And (c) is this Cit, entering the cell from the peritubular side, metabolized to Arg and ornithine (Orn)? Although these questions are raised mainly in connection with mammals, we used the amphibian kidney, which is especially suitable because of its double blood supply, for an initial approach to the problem. After the toad was decapitated, the portal vein, the caval vein and the ureters were catheterized, and the kidneys were perfused through the portal vein (Ringer solution + L- or D-Cit + inulin + p-aminohippurate + L-aspartate). Exclusive peritubular perfusion was assured by showing that inulin perfused into the portal vein did not appear in the urine. During perfusion of the portal vein with L-Cit in a physiological concentration (65 mumol/l), an initial peritubular net uptake of L-Cit of 170 +/- 27 (n = 10) nmol.h-1.g kidney-1 (wet weight) was observed, whereas the value for D-Cit (65 mumol/l) was only 18 +/- 7 (n = 6) nmol.h-1.g-1. After perfusion for 50 min, the uptake of L-Cit reached a steady state with an uptake rate of 108 +/- 5 nmol.h-1.g-1.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M Gekle
- Department of Physiology, University of Würzburg, Federal Republic of Germany
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