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Teixido-Trujillo S, Luis-Lima S, López-Martínez M, Navarro-Díaz M, Díaz-Martín L, Escasany-Martínez E, Gaspari F, Rodríguez-Rodríguez AE. Measured GFR in murine animal models: review on methods, techniques, and procedures. Pflugers Arch 2023; 475:1241-1250. [PMID: 37552296 PMCID: PMC10567863 DOI: 10.1007/s00424-023-02841-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 08/09/2023]
Abstract
Chronic kidney disease (CKD) is one of the most common chronic diseases worldwide, with increasing rates of morbidity and mortality. Thus, early detection is essential to prevent severe adverse events and the progression of kidney disease to an end stage. Glomerular filtration rate (GFR) is the most appropriate index to evaluate renal function in both clinical practice and basic medical research. Several animal models have been developed to understand renal disease induction and progression. Specifically, murine models are useful to study the pathogenesis of renal damage, so a reliable determination of GFR is essential to evaluate the progression of CKD. However, as in clinical practise, the estimation of GFR in murine by levels of serum/urine creatinine or cystatin-C could not be accurate and needed other more reliable methods. As an alternative, the measurement of GFR by the clearance of exogenous markers like inulin, sinistrin, 51Cr-EDTA, 99mTc-DTPA, 125I-iothalamate, or iohexol could be performed. Nevertheless, both approaches-estimation or measurement of GFR-have their limitations and a standard method for the GFR determination has not been defined. Altogether, in this review, we aim to give an overview of the current methods for GFR assessment in murine models, describing each methodology and focusing on their advantages and limitations.
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Affiliation(s)
- Silvia Teixido-Trujillo
- Universidad de La Laguna, Faculty of Medicine, San Cristóbal de La Laguna, Spain
- Research Unit, Hospital Universitario de Canarias, San Cristóbal de La Laguna, Spain
| | - Sergio Luis-Lima
- Department of Laboratory Medicine, Complejo Hospitalario Universitario de Canarias, San Cristóbal de La Laguna, Spain
| | | | - Maruja Navarro-Díaz
- Department of Nephology, Hospital de Sant Joan Despí Moisès Broggi, Barcelona, Spain
| | - Laura Díaz-Martín
- Research Unit, Hospital Universitario de Canarias, San Cristóbal de La Laguna, Spain
- Instituto de Tecnologías Biomédicas (ITB), Universidad de la Laguna, San Cristóbal de La Laguna, Spain
| | - Elia Escasany-Martínez
- Lipobeta group. Departamento de Ciencias Básicas de la Salud, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Spain
| | - Flavio Gaspari
- Instituto di Ricerche Farmacologiche Mario Negri (IRCCS), Clinical Research Center for Rare Diseases 'Aldo & Cele Daccò, Bergamo, Italy
| | - Ana Elena Rodríguez-Rodríguez
- Universidad de La Laguna, Faculty of Medicine, San Cristóbal de La Laguna, Spain.
- Research Unit, Hospital Universitario de Canarias, San Cristóbal de La Laguna, Spain.
- Instituto de Tecnologías Biomédicas (ITB), Universidad de la Laguna, San Cristóbal de La Laguna, Spain.
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Rodrigues AR, Rodrigues CR, Gomes SA, Marques SM, Naves LM, Pedrino GR, de Oliveira-Neto JR, de Carvalho FS, Cruz A, Lião LM, Menegatti R, Carlos da Cunha L. Preclinical pharmacokinetics of a promising antineoplastic prototype piperazine-containing compound (LQFM018) in rats by a new LC-MS/MS bioanalytical method. J Chromatogr B Analyt Technol Biomed Life Sci 2023; 1223:123710. [PMID: 37068313 DOI: 10.1016/j.jchromb.2023.123710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/28/2023] [Accepted: 04/03/2023] [Indexed: 04/19/2023]
Abstract
LQFM018 is a novel antineoplastic prototype, showing an expressive drug-triggered K562 leukemic cells death mechanism, through necroptotic signaling. Due to its promising effect, this study aimed to evaluate the pharmacokinetics of LQFM018 in rats, using a new validated bioanalytical LC-MS/MS-based method. Chromatographic column was an ACE® C18 (100 mm × 4.6 mm, 5 µm) eluted by a mobile phase composed of ammonium acetate 2 mM and formic acid 0.025%:methanol (50:50, v/v), under flow of 1.2 mL/min and injection volume of 3.0 µL. LQFM018 was extracted from rat plasma by a simple liquid-liquid method, using MTBE solvent. Rats were administered intraperitoneally at LQFM018 100 mg/kg dose and blood samples were collect at times of 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 h. Bioanalytical-LC-MS/MS-based method was rapid, high throughput and sensitive with a good linearity ranging from 10 (LLOQ) to 15000 ng/mL, besides precise and accurate, ranging of 0.8-7.3% and 96.8-107.6%, respectively. The prototype LQFM018 was rapid and well absorbed, and highly distributed, apparently due to its high lipid solubility. These features are primordial for an anticancer agent in the treatment of deep tumors, such as bone marrow neoplasms, in which the drug might permeate easily tissue barriers. Also, LQFM018 has demonstrated a high clearance, according to a low t1/2in rats, indicating a relative fast elimination phase related to a possible intense hepatic biotransformation. These information support further studies to establish new understands on pharmacokinetics of promising antineoplastic prototype LQFM018 from preclinical and clinical evaluations.
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Affiliation(s)
- Andryne R Rodrigues
- Center of Studies and Research Toxic-Pharmacological, School of Pharmacy, Federal University of Goias, Goiania, Goias, Brazil
| | - Caroline R Rodrigues
- Center of Studies and Research Toxic-Pharmacological, School of Pharmacy, Federal University of Goias, Goiania, Goias, Brazil
| | - Sandro A Gomes
- Center of Studies and Research Toxic-Pharmacological, School of Pharmacy, Federal University of Goias, Goiania, Goias, Brazil
| | - Stefanne M Marques
- Institute of Biological Sciences, Federal University of Goias, Goiania, Goias, Brazil
| | - Lara M Naves
- Institute of Biological Sciences, Federal University of Goias, Goiania, Goias, Brazil
| | - Gustavo R Pedrino
- Institute of Biological Sciences, Federal University of Goias, Goiania, Goias, Brazil
| | - Jerônimo R de Oliveira-Neto
- Center of Studies and Research Toxic-Pharmacological, School of Pharmacy, Federal University of Goias, Goiania, Goias, Brazil
| | - Flávio S de Carvalho
- Medicinal Pharmaceutical Chemistry Laboratory, School of Pharmacy, Federal University of Goias, Goias, Brazil
| | - Alessandro Cruz
- Center of Studies and Research Toxic-Pharmacological, School of Pharmacy, Federal University of Goias, Goiania, Goias, Brazil.
| | - Luciano M Lião
- Nuclear Magnetic Resonance Laboratory, Chemistry Institute, Federal University of Goias, Goiania, Goias, Brazil
| | - Ricardo Menegatti
- Medicinal Pharmaceutical Chemistry Laboratory, School of Pharmacy, Federal University of Goias, Goias, Brazil
| | - Luiz Carlos da Cunha
- Center of Studies and Research Toxic-Pharmacological, School of Pharmacy, Federal University of Goias, Goiania, Goias, Brazil
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Pais GM, Liu J, Avedissian SN, Hiner D, Xanthos T, Chalkias A, d'Aloja E, Locci E, Gilchrist A, Prozialeck WC, Rhodes NJ, Lodise TP, Fitzgerald JC, Downes KJ, Zuppa AF, Scheetz MH. Lack of synergistic nephrotoxicity between vancomycin and piperacillin/tazobactam in a rat model and a confirmatory cellular model. J Antimicrob Chemother 2021; 75:1228-1236. [PMID: 32011685 DOI: 10.1093/jac/dkz563] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 12/18/2019] [Accepted: 12/19/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Vancomycin and piperacillin/tazobactam are reported in clinical studies to increase acute kidney injury (AKI). However, no clinical study has demonstrated synergistic toxicity, only that serum creatinine increases. OBJECTIVES To clarify the potential for synergistic toxicity between vancomycin, piperacillin/tazobactam and vancomycin + piperacillin/tazobactam treatments by quantifying kidney injury in a translational rat model of AKI and using cell studies. METHODS (i) Male Sprague-Dawley rats (n = 32) received saline, vancomycin 150 mg/kg/day intravenously, piperacillin/tazobactam 1400 mg/kg/day intraperitoneally or vancomycin + piperacillin/tazobactam for 3 days. Urinary biomarkers and histopathology were analysed. (ii) Cellular injury was assessed in NRK-52E cells using alamarBlue®. RESULTS Urinary output increased from Day -1 to Day 1 with vancomycin but only after Day 2 for vancomycin + piperacillin/tazobactam-treated rats. Plasma creatinine was elevated from baseline with vancomycin by Day 2 and only by Day 4 for vancomycin + piperacillin/tazobactam. Urinary KIM-1 and clusterin were increased with vancomycin from Day 1 versus controls (P < 0.001) and only on Day 3 with vancomycin + piperacillin/tazobactam (P < 0.001, KIM-1; P < 0.05, clusterin). The histopathology injury score was elevated only in the vancomycin group when compared with piperacillin/tazobactam as a control (P = 0.04) and generally not so with vancomycin + piperacillin/tazobactam. In NRK-52E cells, vancomycin induced cell death with high doses (IC50 48.76 mg/mL) but piperacillin/tazobactam did not, and vancomycin + piperacillin/tazobactam was similar to vancomycin. CONCLUSIONS All groups treated with vancomycin demonstrated AKI; however, vancomycin + piperacillin/tazobactam was not worse than vancomycin. Histopathology suggested that piperacillin/tazobactam did not worsen vancomycin-induced AKI and may even be protective.
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Affiliation(s)
- Gwendolyn M Pais
- Department of Pharmacy Practice, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, USA.,Midwestern University, Chicago College of Pharmacy Pharmacometrics Center of Excellence, Downers Grove, IL, USA
| | - Jiajun Liu
- Department of Pharmacy Practice, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, USA.,Midwestern University, Chicago College of Pharmacy Pharmacometrics Center of Excellence, Downers Grove, IL, USA
| | - Sean N Avedissian
- Department of Pharmacy Practice, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, USA.,Midwestern University, Chicago College of Pharmacy Pharmacometrics Center of Excellence, Downers Grove, IL, USA
| | - Danielle Hiner
- Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, USA
| | | | | | - Ernesto d'Aloja
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Emanuela Locci
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Annette Gilchrist
- Midwestern University, Chicago College of Pharmacy Pharmacometrics Center of Excellence, Downers Grove, IL, USA.,Department of Pharmaceutical Sciences, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, USA
| | - Walter C Prozialeck
- Department of Pharmacology, College of Graduate Studies, Midwestern University, Downers Grove, IL, USA
| | - Nathaniel J Rhodes
- Department of Pharmacy Practice, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, USA.,Midwestern University, Chicago College of Pharmacy Pharmacometrics Center of Excellence, Downers Grove, IL, USA
| | - Thomas P Lodise
- Department of Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY, USA
| | - Julie C Fitzgerald
- Division of Critical Care, Department of Anesthesiology and Critical Care, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Kevin J Downes
- Division of Infectious Diseases, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Pediatrics, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Athena F Zuppa
- Division of Critical Care, Department of Anesthesiology and Critical Care, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Marc H Scheetz
- Department of Pharmacy Practice, Chicago College of Pharmacy, Midwestern University, Downers Grove, IL, USA.,Midwestern University, Chicago College of Pharmacy Pharmacometrics Center of Excellence, Downers Grove, IL, USA.,Department of Pharmacology, College of Graduate Studies, Midwestern University, Downers Grove, IL, USA
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A Clinically Relevant Functional Model of Type-2 Cardio-Renal Syndrome with Paraventricular Changes consequent to Chronic Ischaemic Heart Failure. Sci Rep 2020; 10:1261. [PMID: 31988300 PMCID: PMC6985167 DOI: 10.1038/s41598-020-58071-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/24/2019] [Indexed: 11/25/2022] Open
Abstract
Cardiorenal syndrome, de novo renal pathology arising secondary to cardiac insufficiency, is clinically recognised but poorly characterised. This study establishes and characterises a valid model representative of Type 2 cardiorenal syndrome. Extensive permanent left ventricular infarction, induced by ligation of the left anterior descending coronary artery in Lewis rats, was confirmed by plasma cardiac troponin I, histology and cardiac haemodynamics. Renal function and morphology was assessed 90-days post-ligation when heart failure had developed. The involvement of the paraventricular nucleus was investigated using markers of inflammation, apoptosis, reactive oxygen species and of angiotensin II involvement. An extensive left ventricular infarct was confirmed following coronary artery ligation, resulting in increased left ventricular weight and compromised left ventricular diastolic function and developed pressure. Glomerular filtration was significantly decreased, fractional excretion of sodium and caspase activities were increased and basement membrane thickening, indicating glomerulosclerosis, was evident. Interestingly, angiotensin II receptor I expression and reactive oxygen species levels in the hypothalamic paraventricular nucleus remained significantly increased at 90-days post-coronary artery ligation, suggesting that these hypothalamic changes may represent a novel, valuable pharmacological target. This model provides conclusive morphological, biochemical and functional evidence of renal injury consequent to heart failure, truly representative of Type-2 cardiorenal syndrome.
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Edwards A, McDonough AA. Impact of angiotensin II-mediated stimulation of sodium transporters in the nephron assessed by computational modeling. Am J Physiol Renal Physiol 2019; 317:F1656-F1668. [PMID: 31657247 DOI: 10.1152/ajprenal.00335.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Angiotensin II (ANG II) raises blood pressure partly by stimulating tubular Na+ reabsorption. The effects of ANG II on tubular Na+ transporters (i.e., channels, pumps, cotransporters, and exchangers) vary between short-term and long-term exposure. To better understand the physiological impact, we used a computational model of transport along the rat nephron to predict the effects of short- and long-term ANG II-induced transporter activation on Na+ and K+ reabsorption/secretion, and to compare measured and calculated excretion rates. Three days of ANG II infusion at 200 ng·kg-1·min-1 is nonpressor, yet stimulates transporter accumulation. The increase in abundance of Na+/H+ exchanger 3 (NHE3) or activated Na+-K+-2Cl- cotransporter-2 (NKCC2-P) predicted significant reductions in urinary Na+ excretion, yet there was no observed change in urine Na+. The lack of antinatriuresis, despite Na+ transporter accumulation, was supported by Li+ and creatinine clearance measurements, leading to the conclusion that 3-day nonpressor ANG II increases transporter abundance without proportional activation. Fourteen days of ANG II infusion at 400 ng·kg-1·min-1 raises blood pressure and increases Na+ transporter abundance along the distal nephron; proximal tubule and medullary loop transporters are decreased and urine Na+ and volume output are increased, evidence for pressure natriuresis. Simulations indicate that decreases in NHE3 and NKCC2-P contribute significantly to reducing Na+ reabsorption along the nephron and to pressure natriuresis. Our results also suggest that differential regulation of medullary (decrease) and cortical (increase) NKCC2-P is important to preserve K+ while minimizing Na+ retention during ANG II infusion. Lastly, our model indicates that accumulation of active Na+-Cl- cotransporter counteracts epithelial Na+ channel-induced urinary K+ loss.
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Affiliation(s)
- Aurélie Edwards
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Alicia A McDonough
- Department of Physiology and Neuroscience, Keck School of Medicine of University of Southern California, Los Angeles, California
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Barone S, Xu J, Zahedi K, Brooks M, Soleimani M. Probenecid Pre-treatment Downregulates the Kidney Cl -/HCO 3- Exchanger (Pendrin) and Potentiates Hydrochlorothiazide-Induced Diuresis. Front Physiol 2018; 9:849. [PMID: 30050451 PMCID: PMC6050369 DOI: 10.3389/fphys.2018.00849] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/14/2018] [Indexed: 01/14/2023] Open
Abstract
Background: Probenecid is a uricosuric agent that in addition to exerting a positive ionotropic effect in the heart, blocks the ATP transporter Pannexin 1 and inhibits the Cl-/HCO3- exchanger, pendrin. In the kidney, pendrin blunts the loss of salt wasting secondary to the inhibition of the thiazide-sensitive Na+-Cl- co-transporter (NCC/SLC12A3). Hypothesis: Pre-treatment with probenecid down-regulates pendrin; therefore, leaving NCC as the main salt absorbing transporter in the distal nephron, and hence enhances the hydrochlorothiazide (HCTZ)-induced diuresis. Methods: Daily balance studies, blood and urine chemical analysis, immunofluorescence, as well as western and northern blot analyses were utilized to examine the effects of probenecid alone (at 250 mg/kg/day) or in combination with HCTZ (at 40 mg/kg/day) on kidney function and on salt and water transporters in the collecting duct. Results: Male Sprague Dawley rats were subjected to three different protocols: (1) HCTZ for 4 days, (2) probenecid for 10 days, and (3) primed with probenecid for 6 days followed by probenecid and HCTZ for 4 additional days. Treatment protocol 1 (HCTZ for 4 days) only mildly increased the urine volume (U Vol) from a baseline of 9.8-13.4 ml/day. In response to treatment protocol 2 (probenecid for 10 days), U Vol increased to 15.9 ml/24 h. Treatment protocol 3 (probenecid for 6 days followed by probenecid and HCTZ for 4 additional days) increased the U Vol to 42.9 ml/day on day 4 of co-treatment with HCTZ and probenecid (compared to probenecid p = 0.003, n = 5 or HCTZ alone p = 0.001, n = 5). Probenecid treatment at 250 mg/kg/day downregulated the expression of pendrin and led to a decrease in AQP2 expression. Enhanced diuresis by probenecid plus HCTZ was not associated with volume depletion. Conclusion: Probenecid pre-treatment downregulates pendrin and robustly enhances diuresis by HCTZ-mediated NCC inhibition in kidney.
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Affiliation(s)
- Sharon Barone
- Department of Medicine, University of Cincinnati, Cincinnati, OH, United States
- Research Services, VA Medical Center, Cincinnati, OH, United States
| | - Jie Xu
- Department of Medicine, University of Cincinnati, Cincinnati, OH, United States
- Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, OH, United States
| | - Kamyar Zahedi
- Department of Medicine, University of Cincinnati, Cincinnati, OH, United States
- Research Services, VA Medical Center, Cincinnati, OH, United States
| | - Marybeth Brooks
- Department of Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Manoocher Soleimani
- Department of Medicine, University of Cincinnati, Cincinnati, OH, United States
- Research Services, VA Medical Center, Cincinnati, OH, United States
- Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, OH, United States
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Evaluation of KIM-1 as an early biomarker of snakebite-induced AKI in mice. Toxicon 2018; 151:24-28. [PMID: 29909065 DOI: 10.1016/j.toxicon.2018.06.074] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 06/13/2018] [Accepted: 06/14/2018] [Indexed: 01/10/2023]
Abstract
Acute kidney injury (AKI) is one of the most important complications of bothropic poisoning and its early identification remains challenging. The nephrotoxicity of Bothrops insularis venom (BinsV) was previously described by our research group. In this study, we continued to evaluate the effect of BinsV on kidney function in mice and LLC-MK2 proximal tubule cells, evaluating KIM-1 protein as an early AKI biomarker. Male Swiss mice were inoculated with BinsV intramuscularly and observed for 24 h in a metabolic cage model. Urine and blood were collected for biochemical analyses and the kidneys were examined for oxide-reducing balance and submitted to histological analysis. LLC-MK2 cells incubated with BinsV were assessed for cell viability and cell death mechanism by flow cytometry. Histological analysis of the kidneys indicated AKI and the oxide-reducing analyses demonstrated a decreasing in reduced glutathione (GSH) levels and an increasing on Malondialdehyde (MDA) levels. BinsV was cytotoxic to LLC-MK2 and the cytometry analyses suggested necrosis. Within 24 h after the envenomation, urinary creatinine did not increase, but the urinary levels of KIM-1 increased. In conclusion, we found AKI evidence in the kidney tissue and the increase in the KIM-1 levels suggest it can be used as an early AKI biomarker.
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Wijerathna TM, Gawarammana IB, Dissanayaka DM, Palanagasinghe C, Shihana F, Dassanayaka G, Shahmy S, Endre ZH, Mohamed F, Buckley NA. Serum creatinine and cystatin C provide conflicting evidence of acute kidney injury following acute ingestion of potassium permanganate and oxalic acid. Clin Toxicol (Phila) 2017; 55:970-976. [PMID: 28535124 DOI: 10.1080/15563650.2017.1326607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
AIM Acute kidney injury (AKI) is common following deliberate self-poisoning with a combination washing powder containing oxalic acid (H2C2O4) and potassium permanganate (KMnO4). Early and rapid increases in serum creatinine (sCr) follow severe poisoning. We investigated the relationship of these increases with direct nephrotoxicity in an ongoing multicenter prospective cohort study in Sri Lanka exploring AKI following poisoning. METHODS Multiple measures of change in kidney function were evaluated in 48 consenting patients who had serial sCr and serum cystatin C (sCysC) data available. RESULTS Thirty-eight (38/48, 79%) patients developed AKI (AKIN criteria). Twenty-eight (58%) had AKIN stage 2 or 3. Initial increases in urine creatinine (uCr) excretion were followed by a substantial loss of renal function. The AKIN stage 2 and 3 (AKIN2/3) group had very rapid rises in sCr (a median of 118% at 24 h and by 400% at 72 h post ingestion). We excluded the possibility that the rapid rise resulted from the assay used or muscle damage. In contrast, the average sCysC increase was 65% by 72 h. CONCLUSIONS In most AKI, sCysC increases to the same extent but more rapidly than sCr, as sCysC has a shorter half-life. This suggests either a reduction in Cystatin C production or, conversely, that the rapid early rise of sCr results from increased production of creatine and creatinine to meet energy demands following severe oxidative stress mediated by H2C2O4 and KMnO4. Increased early creatinine excretion supports the latter explanation, since creatinine excretion usually decreases transiently in AKIN2/3 from other causes.
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Affiliation(s)
- Thilini Madushanka Wijerathna
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka.,b Department of Pathology, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka
| | - Indika Bandara Gawarammana
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka.,c Department of Medicine, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka
| | | | - Chathura Palanagasinghe
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka
| | - Fathima Shihana
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka.,d Clinical Pharmacology and Toxicology Research Group, Discipline of Pharmacology, Sydney Medical School, University of Sydney , Sydney , Australia
| | - Gihani Dassanayaka
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka
| | - Seyed Shahmy
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka
| | - Zoltan Huba Endre
- e Australian Kidney Biomarker Reference Laboratory, Department of Nephrology , Prince of Wales Hospital and Clinical School, University of New South Wales , Sydney , Australia
| | - Fahim Mohamed
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka.,d Clinical Pharmacology and Toxicology Research Group, Discipline of Pharmacology, Sydney Medical School, University of Sydney , Sydney , Australia.,e Australian Kidney Biomarker Reference Laboratory, Department of Nephrology , Prince of Wales Hospital and Clinical School, University of New South Wales , Sydney , Australia.,f Department of Pharmacy, Faculty of Allied Health Science , University of Peradeniya , Peradeniya , Sri Lanka
| | - Nicholas Alan Buckley
- a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka.,d Clinical Pharmacology and Toxicology Research Group, Discipline of Pharmacology, Sydney Medical School, University of Sydney , Sydney , Australia
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9
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Zhao H, Liu YJ, Liu ZR, Tang DD, Chen XW, Chen YH, Zhou RN, Chen SQ, Niu HX. Role of mitochondrial dysfunction in renal fibrosis promoted by hypochlorite-modified albumin in a remnant kidney model and protective effects of antioxidant peptide SS-31. Eur J Pharmacol 2017; 804:57-67. [PMID: 28322835 DOI: 10.1016/j.ejphar.2017.03.037] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/13/2017] [Accepted: 03/16/2017] [Indexed: 12/22/2022]
Abstract
Oxidative stress aggravates renal fibrosis, a pathway involved in almost all forms of chronic kidney disease (CKD). However, the underlying mechanism involved in the pathogenesis of renal oxidative stress has not been completely elucidated. In this study, we explored the role and mechanism of hypochlorite-modified albumin (HOCl-alb) in mediating oxidative stress and fibrotic response in a remnant-kidney rat model. Five-sixths nephrectomy (5/6 NX) was performed on the rats and then the animals were randomly assigned to intravenous treatment with either vehicle alone, or HOCl-rat serum albumin (RSA) in the presence or absence of SS-31 (administered intraperitoneally). A sham-operation control group was set up concurrently. Compared with the control group, 5/6 NX animals displayed marked mitochondrial (mt) dysfunction, as evidenced by decrease of mitochondrial membrane potential (MMP), ATP production, mtDNA copy number alterations and manganese superoxide dismutase (MnSOD) activity, release of cytochrome C (Cyto C) from mitochondria to the cytoplasm, and increase of mitochondrial reactive oxygen species in renal tissues. They also displayed increased levels of HOCl-alb in both plasma and renal tissues. These changes were accompanied by accumulation of extracellular matrix, worsened proteinuria, deteriorated renal function, and a marked increase of macrophage infiltration along with up-regulation of monocyte chemoattractant protein (MCP)-1 and transforming growth factor (TGF)-β1 expression. HOCl-alb challenge further exacerbated the above biological effects in 5/6 NX animals, but these adverse effects were prevented by administration of SS-31, a mitochondrial targeted antioxidant peptide. These data suggest that accumulation of HOCl-alb may promote renal inflammation and fibrosis, probably related to mitochondrial oxidative stress and dysfunction and that the mitochondrial targeted peptide SS-31 might be a novel therapy for renal fibrosis and chronic renal failure (CRF).
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Affiliation(s)
- Hao Zhao
- Division of Nephrology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Yan-Jun Liu
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515,China
| | - Zong-Rui Liu
- Division of Nephrology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China; Division of Nephrology, Taian City Central Hospital, Taian 271000, China
| | - Dong-Dong Tang
- Division of Nephrology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China; Division of Nephrology, Huadu District people's Hospital, Southern Medical University, Guangzhou 510800, China
| | - Xiao-Wen Chen
- Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - Yi-Hua Chen
- Division of Nephrology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Ru-Ning Zhou
- Southern Medical University, Guangzhou 510515, China
| | - Si-Qi Chen
- Division of Nephrology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Hong-Xin Niu
- Division of Nephrology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China.
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10
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Sampaio TL, Menezes RRPPBD, da Costa MFB, Meneses GC, Arrieta MCV, Chaves Filho AJM, de Morais GB, Libório AB, Alves RS, Evangelista JSAM, Martins AMC. Nephroprotective effects of (-)-α-bisabolol against ischemic-reperfusion acute kidney injury. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2016; 23:1843-1852. [PMID: 27912887 DOI: 10.1016/j.phymed.2016.11.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 10/28/2016] [Accepted: 11/10/2016] [Indexed: 05/14/2023]
Abstract
BACKGROUND Ischemia/reperfusion (I/R) in kidney is commonly related to acute kidney injury (AKI), essentially through oxidative stress. (-)-α-Bisabolol is a sesquiterpene isolated from the essential oil of a variety of plants, including chamomile, which has important antioxidant activity. STUDY DESIGN This study intends to evaluate the nephroprotective activity of (-)-α-bisabolol (Bis) in both in vivo and in vitro models of kidney I/R. METHODS Male Wistar rats were submitted to right nephrectomy, followed by ischemia by clamping of the renal artery in the left kidney for 60min. and 48h of reperfusion. The animals were treated orally with Bis (100mg/kg) or vehicle for 24h after reperfusion, and placed in metabolic cages, to evaluate water consumption, diuresis, urinary osmolality, classic biochemical markers and urinary KIM-1 (kidney injury molecule-1). Additionally, the left kidney was collected for histological evaluation and determination of glutathione (GSH) and Thiobarbituric Acid Reactive Substances (TBARS) levels. Tubular epithelial cells LLC-MK2 were used to assess Bis effect on in vitro I/R, by MTT assay. It was performed the cellular respiration tests by flow cytometry: evaluation of the production of cytoplasmic reactive oxygen species by DCFH-DA assay and mitochondrial transmembrane potential analysis with the dye rhodamine 123. RESULTS I/R caused alterations in diuresis, water intake, urinary osmolality, plasmatic creatinine, urea and uric acid, creatinine clearance, proteinuria and microalbuminuria. Treatment with Bis ameliorated all of these parameters. Also, KIM-1 level enhanced by I/R was also diminished in groups treated with Bis. The histological examination showed that Bis attenuated the morphological changes caused by I/R, markedly vascular congestion and intratubular deposits of proteinaceous material. Additionally, Bis was able to reduce the changes observed in TBARS and GSH levels in kidney tissue. In in vitro assay, Bis was capable to partially protect the cell lineage against cell damage induced by I/R. CONCLUSION (-)-α-Bisabolol has a nephroprotective effect in kidney I/R, with antioxidant effect. Moreover, this result seems to be associated to a direct protective effect on tubular epithelia.
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Affiliation(s)
- Tiago Lima Sampaio
- Department of Physiology and Pharmacology, School of Medicine, Federal University of Ceará, Ceará, Brazil
| | | | | | | | | | | | | | - Alexandre Braga Libório
- Department of Clinical Medicine, School of Medicine, Federal University of Ceará, Fortaleza, Ceara, Brazil
| | - Renata Sousa Alves
- Department of Clinical and Toxicological Analysis, School of Pharmacy, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | - Alice Maria Costa Martins
- Department of Clinical and Toxicological Analysis, School of Pharmacy, Federal University of Ceará, Fortaleza, Ceará, Brazil
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11
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Fong D, Ullah MM, Lal JG, Abdelkader A, Ow CP, Hilliard LM, Ricardo SD, Kelly DJ, Evans RG. Renal cellular hypoxia in adenine-induced chronic kidney disease. Clin Exp Pharmacol Physiol 2016; 43:896-905. [DOI: 10.1111/1440-1681.12621] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 05/30/2016] [Accepted: 07/02/2016] [Indexed: 01/20/2023]
Affiliation(s)
- Debra Fong
- Biomedicine Discovery Institute and Department of Physiology; Monash University; Clayton Melbourne Vic. Australia
| | - Md Mahbub Ullah
- Biomedicine Discovery Institute and Department of Physiology; Monash University; Clayton Melbourne Vic. Australia
| | - Jaswini G. Lal
- Biomedicine Discovery Institute and Department of Physiology; Monash University; Clayton Melbourne Vic. Australia
| | - Amany Abdelkader
- Biomedicine Discovery Institute and Department of Physiology; Monash University; Clayton Melbourne Vic. Australia
| | - Connie P.C. Ow
- Biomedicine Discovery Institute and Department of Physiology; Monash University; Clayton Melbourne Vic. Australia
| | - Lucinda M. Hilliard
- Biomedicine Discovery Institute and Department of Physiology; Monash University; Clayton Melbourne Vic. Australia
| | - Sharon D. Ricardo
- Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology; Monash University; Clayton Melbourne Vic. Australia
| | - Darren J. Kelly
- Department of Medicine; University of Melbourne; St Vincent's Hospital; Fitzroy Melbourne Vic. Australia
| | - Roger G. Evans
- Biomedicine Discovery Institute and Department of Physiology; Monash University; Clayton Melbourne Vic. Australia
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12
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Carrara F, Azzollini N, Nattino G, Corna D, Villa S, Cerullo D, Zoja C, Abrante B, Luis-Lima S, Porrini E, Cannata A, Ferrari S, Fois M, Stucchi N, Gaspari F. Simplified Method to Measure Glomerular Filtration Rate by Iohexol Plasma Clearance in Conscious Rats. Nephron Clin Pract 2016; 133:62-70. [DOI: 10.1159/000445843] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/23/2016] [Indexed: 11/19/2022] Open
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13
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Satoh H, Nomiya N, Imai D, Sato S, Sakurai K, Takasuna K, Furuhama K. A method for estimating the glomerular filtration rate in conscious monkeys. J Appl Toxicol 2015; 36:266-70. [DOI: 10.1002/jat.3178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 04/20/2015] [Accepted: 04/21/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Hiroshi Satoh
- Cooperative Department of Veterinary Medicine; Iwate University; 3-18-8 Ueda Morioka Iwate 020-8550 Japan
| | - Nana Nomiya
- Cooperative Department of Veterinary Medicine; Iwate University; 3-18-8 Ueda Morioka Iwate 020-8550 Japan
| | - Daiki Imai
- Cooperative Department of Veterinary Medicine; Iwate University; 3-18-8 Ueda Morioka Iwate 020-8550 Japan
| | - Shigeru Sato
- Cooperative Department of Veterinary Medicine; Iwate University; 3-18-8 Ueda Morioka Iwate 020-8550 Japan
| | - Ken Sakurai
- Medicinal Safety Research Laboratories; Daiichi Sankyo Co., Ltd.; 1-16-13 Kita-Kasai Edogawa-ku Tokyo 134-0081 Japan
| | - Kiyoshi Takasuna
- Medicinal Safety Research Laboratories; Daiichi Sankyo Co., Ltd.; 1-16-13 Kita-Kasai Edogawa-ku Tokyo 134-0081 Japan
| | - Kazuhisa Furuhama
- Cooperative Department of Veterinary Medicine; Iwate University; 3-18-8 Ueda Morioka Iwate 020-8550 Japan
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14
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Ow CPC, Abdelkader A, Hilliard LM, Phillips JK, Evans RG. Determinants of renal tissue hypoxia in a rat model of polycystic kidney disease. Am J Physiol Regul Integr Comp Physiol 2014; 307:R1207-15. [DOI: 10.1152/ajpregu.00202.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Renal tissue oxygen tension (Po2) and its determinants have not been quantified in polycystic kidney disease (PKD). Therefore, we measured kidney tissue Po2 in the Lewis rat model of PKD (LPK) and in Lewis control rats. We also determined the relative contributions of altered renal oxygen delivery and consumption to renal tissue hypoxia in LPK rats. Po2 of the superficial cortex of 11- to 13-wk-old LPK rats, measured by Clark electrode with the rat under anesthesia, was higher within the cysts (32.8 ± 4.0 mmHg) than the superficial cortical parenchyma (18.3 ± 3.5 mmHg). Po2 in the superficial cortical parenchyma of Lewis rats was 2.5-fold greater (46.0 ± 3.1 mmHg) than in LPK rats. At each depth below the cortical surface, tissue Po2 in LPK rats was approximately half that in Lewis rats. Renal blood flow was 60% less in LPK than in Lewis rats, and arterial hemoglobin concentration was 57% less, so renal oxygen delivery was 78% less. Renal venous Po2 was 38% less in LPK than Lewis rats. Sodium reabsorption was 98% less in LPK than Lewis rats, but renal oxygen consumption did not significantly differ between the two groups. Thus, in this model of PKD, kidney tissue is severely hypoxic, at least partly because of deficient renal oxygen delivery. Nevertheless, the observation of similar renal oxygen consumption, despite markedly less sodium reabsorption, in the kidneys of LPK compared with Lewis rats, indicates the presence of inappropriately high oxygen consumption in the polycystic kidney.
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Affiliation(s)
- Connie P. C. Ow
- Department of Physiology Monash University, Melbourne, Australia; and
| | - Amany Abdelkader
- Department of Physiology Monash University, Melbourne, Australia; and
| | | | | | - Roger G. Evans
- Department of Physiology Monash University, Melbourne, Australia; and
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15
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Comparison of renal biomarkers with glomerular filtration rate in susceptibility to the detection of gentamicin-induced acute kidney injury in dogs. J Comp Pathol 2014; 151:264-70. [PMID: 25086870 DOI: 10.1016/j.jcpa.2014.06.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 06/02/2014] [Accepted: 06/06/2014] [Indexed: 11/22/2022]
Abstract
Fourteen renal biomarkers were compared with measurement of glomerular filtration rate (GFR) in detecting acute kidney injury (AKI) in beagle dogs given gentamicin (40 mg/kg/day by subcutaneous injection) for 7 consecutive days. Serum and urinary biomarkers were measured before administration of gentamicin and then on days 4 and 8 after starting administration. GFR was derived by use of a simplified equation. Increased urinary cystatin C and decreased GFR occurred from day 4 and were detected before increases in blood urea nitrogen (BUN) and serum creatinine concentrations and changes in other urinary parameters. The closest correlation was between urinary cystatin C and GFR. At termination, microscopical examination revealed extensive necrosis of proximal tubular epithelium with hyaline casts in the kidney of treated dogs. These data indicate that urinary cystatin C is the most sensitive index of kidney injury and GFR reflects the kidney functional mass.
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16
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Lepist EI, Zhang X, Hao J, Huang J, Kosaka A, Birkus G, Murray BP, Bannister R, Cihlar T, Huang Y, Ray AS. Contribution of the organic anion transporter OAT2 to the renal active tubular secretion of creatinine and mechanism for serum creatinine elevations caused by cobicistat. Kidney Int 2014; 86:350-7. [PMID: 24646860 PMCID: PMC4120670 DOI: 10.1038/ki.2014.66] [Citation(s) in RCA: 180] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 01/08/2014] [Accepted: 01/16/2014] [Indexed: 02/02/2023]
Abstract
Many xenobiotics including the pharmacoenhancer cobicistat increase serum creatinine by inhibiting its renal active tubular secretion without affecting the glomerular filtration rate. This study aimed to define the transporters involved in creatinine secretion, applying that knowledge to establish the mechanism for xenobiotic-induced effects. The basolateral uptake transporters organic anion transporter OAT2 and organic cation transporters OCT2 and OCT3 were found to transport creatinine. At physiologic creatinine concentrations, the specific activity of OAT2 transport was over twofold higher than OCT2 or OCT3, establishing OAT2 as a likely relevant creatinine transporter and further challenging the traditional view that creatinine is solely transported by a cationic pathway. The apical multidrug and toxin extrusion transporters MATE1 and MATE2-K demonstrated low-affinity and high-capacity transport. All drugs known to affect creatinine inhibited OCT2 and MATE1. Similar to cimetidine and ritonavir, cobicistat had the greatest effect on MATE1 with a 50% inhibition constant of 0.99 μM for creatinine transport. Trimethoprim potently inhibited MATE2-K, whereas dolutegravir preferentially inhibited OCT2. Cimetidine was unique, inhibiting all transporters that interact with creatinine. Thus, the clinical observation of elevated serum creatinine in patients taking cobicistat is likely a result of OCT2 transport, facilitating intracellular accumulation, and MATE1 inhibition.
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Affiliation(s)
| | | | - Jia Hao
- Gilead Sciences, Foster City, California, USA
| | - Jane Huang
- Optivia Biotechnology, Menlo Park, California, USA
| | - Alan Kosaka
- Optivia Biotechnology, Menlo Park, California, USA
| | | | | | | | | | - Yong Huang
- Optivia Biotechnology, Menlo Park, California, USA
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17
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Stockand JD, Vallon V, Ortiz P. In vivo and ex vivo analysis of tubule function. Compr Physiol 2013; 2:2495-525. [PMID: 23720256 DOI: 10.1002/cphy.c100051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Analysis of tubule function with in vivo and ex vivo approaches has been instrumental in revealing renal physiology. This work allows assignment of functional significance to known gene products expressed along the nephron, primary of which are proteins involved in electrolyte transport and regulation of these transporters. Not only we have learned much about the key roles played by these transport proteins and their proper regulation in normal physiology but also the combination of contemporary molecular biology and molecular genetics with in vivo and ex vivo analysis opened a new era of discovery informative about the root causes of many renal diseases. The power of in vivo and ex vivo analysis of tubule function is that it preserves the native setting and control of the tubule and proteins within tubule cells enabling them to be investigated in a "real-life" environment with a high degree of precision. In vivo and ex vivo analysis of tubule function continues to provide a powerful experimental outlet for testing, evaluating, and understanding physiology in the context of the novel information provided by sequencing of the human genome and contemporary genetic screening. These tools will continue to be a mainstay in renal laboratories as this discovery process continues and as we continue to identify new gene products functionally compromised in renal disease.
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Affiliation(s)
- James D Stockand
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, USA.
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18
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van Koppen A, Verhaar MC, Bongartz LG, Joles JA. 5/6th nephrectomy in combination with high salt diet and nitric oxide synthase inhibition to induce chronic kidney disease in the Lewis rat. J Vis Exp 2013:e50398. [PMID: 23851420 DOI: 10.3791/50398] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Chronic kidney disease (CKD) is a global problem. Slowing CKD progression is a major health priority. Since CKD is characterized by complex derangements of homeostasis, integrative animal models are necessary to study development and progression of CKD. To study development of CKD and novel therapeutic interventions in CKD, we use the 5/6th nephrectomy ablation model, a well known experimental model of progressive renal disease, resembling several aspects of human CKD. The gross reduction in renal mass causes progressive glomerular and tubulo-interstitial injury, loss of remnant nephrons and development of systemic and glomerular hypertension. It is also associated with progressive intrarenal capillary loss, inflammation and glomerulosclerosis. Risk factors for CKD invariably impact on endothelial function. To mimic this, we combine removal of 5/6th of renal mass with nitric oxide (NO) depletion and a high salt diet. After arrival and acclimatization, animals receive a NO synthase inhibitor (NG-nitro-L-Arginine) (L-NNA) supplemented to drinking water (20 mg/L) for a period of 4 weeks, followed by right sided uninephrectomy. One week later, a subtotal nephrectomy (SNX) is performed on the left side. After SNX, animals are allowed to recover for two days followed by LNNA in drinking water (20 mg/L) for a further period of 4 weeks. A high salt diet (6%), supplemented in ground chow (see time line Figure 1), is continued throughout the experiment. Progression of renal failure is followed over time by measuring plasma urea, systolic blood pressure and proteinuria. By six weeks after SNX, renal failure has developed. Renal function is measured using 'gold standard' inulin and para-amino hippuric acid (PAH) clearance technology. This model of CKD is characterized by a reduction in glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), hypertension (systolic blood pressure>150 mmHg), proteinuria (> 50 mg/24 hr) and mild uremia (>10 mM). Histological features include tubulo-interstitial damage reflected by inflammation, tubular atrophy and fibrosis and focal glomerulosclerosis leading to massive reduction of healthy glomeruli within the remnant population (<10%). Follow-up until 12 weeks after SNX shows further progression of CKD.
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Affiliation(s)
- Arianne van Koppen
- Department of Nephrology & Hypertension, University Medical Center Utrecht.
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19
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Murayama I, Miyano A, Sasaki Y, Kimura A, Sato S, Furuhama K. Glomerular filtration rate in Holstein dairy cows estimated from a single blood sample using iodixanol. J Dairy Sci 2013; 96:5120-8. [PMID: 23791486 DOI: 10.3168/jds.2013-6884] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 05/09/2013] [Indexed: 11/19/2022]
Abstract
The isotonic, nonionic, contrast medium iodixanol, as a test substance, was compared with the conventional glomerular filtration rate (GFR) tracer inulin to establish a simplified procedure for estimating the GFR in Holstein dairy cows. First, inulin and iodixanol were coadministered as a bolus intravenous injection to clinically healthy cows at 30 mg/kg and 10mg of I/kg of body weight, respectively, followed by blood collection for multisample strategies. Serum iodixanol and inulin concentrations were separately determined by using HPLC and colorimetry, respectively, and blood urea nitrogen and creatinine concentrations in sera were measured. In the multisample method, the GFR values estimated by iodixanol were consistent with those estimated by inulin. No effects of body weight, age, or parity on GFR estimates were noted with either protocol used. No difference was observed between the GFR values obtained from nonlactating and lactating cows, suggesting that no transfer of iodixanol to milk occurred. An equation for calculating the GFR in the single-sample method was derived from the injected dose, sampling time, serum concentration, and estimated volume of distribution based on data from the multisample method in clinically healthy cows and cows with reduced renal function. The GFR values estimated by the single-sample method were in good agreement with those calculated by using the multisample method. These results demonstrate that the single-sample method using iodixanol can be applied as an alternative procedure for screening GFR in dairy cows.
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Affiliation(s)
- I Murayama
- Miyagi Prefectural Federation of Agricultural Mutual Aid Association, Miyagi 989-0731, Japan
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20
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Rieg T. A High-throughput method for measurement of glomerular filtration rate in conscious mice. J Vis Exp 2013:e50330. [PMID: 23712131 DOI: 10.3791/50330] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The measurement of glomerular filtration rate (GFR) is the gold standard in kidney function assessment. Currently, investigators determine GFR by measuring the level of the endogenous biomarker creatinine or exogenously applied radioactive labeled inulin ((3)H or (14)C). Creatinine has the substantial drawback that proximal tubular secretion accounts for ~50% of total renal creatinine excretion and therefore creatinine is not a reliable GFR marker. Depending on the experiment performed, inulin clearance can be determined by an intravenous single bolus injection or continuous infusion (intravenous or osmotic minipump). Both approaches require the collection of plasma or plasma and urine, respectively. Other drawbacks of radioactive labeled inulin include usage of isotopes, time consuming surgical preparation of the animals, and the requirement of a terminal experiment. Here we describe a method which uses a single bolus injection of fluorescein isothiocyanate-(FITC) labeled inulin and the measurement of its fluorescence in 1-2 μl of diluted plasma. By applying a two-compartment model, with 8 blood collections per mouse, it is possible to measure GFR in up to 24 mice per day using a special work-flow protocol. This method only requires brief isoflurane anesthesia with all the blood samples being collected in a non-restrained and awake mouse. Another advantage is that it is possible to follow mice over a period of several months and treatments (i.e. doing paired experiments with dietary changes or drug applications). We hope that this technique of measuring GFR is useful to other investigators studying mouse kidney function and will replace less accurate methods of estimating kidney function, such as plasma creatinine and blood urea nitrogen.
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Affiliation(s)
- Timo Rieg
- Division of Nephrology-Hypertension, Department of Medicine, University of California, San Diego, USA.
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21
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Kanbak G, Uzuner K, Kuşat Ol K, Oğlakçı A, Kartkaya K, Şentürk H. Effect of kefir and low-dose aspirin on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet. Clin Exp Hypertens 2013; 36:1-8. [PMID: 23631764 DOI: 10.3109/10641963.2013.783046] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract We aim to study the effect of low-dose aspirin and kefir on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet. Forty adult male Sprague-Dawley rats were divided into five groups: control, high-salt (HS) (8.0% NaCl), HS+aspirin (10 mg/kg), HS+kefir (10.0%w/v), HS+aspirin +kefir. We measured sistolic blood pressure (SBP), mean arterial pressure (MAP), diastolic pressure, pulse pressure in the rats. Cathepsin B, L, DNA fragmentation and caspase-3 activities were determined from rat kidney tissues and rats clearance of creatinine calculated. Although HS diet increased significantly SBP, MAP, diastolic pressure, pulse pressure parameters compared the control values. They were not as high as accepted hypertension levels. When compared to HS groups, kefir groups significantly decrease Cathepsin B and DNA fragmentation levels. Caspase levels were elevated slightly in other groups according to control group. While, we also found that creatinine clearance was higher in HS+kefir and HS+low-dose aspirin than HS group. Thus, using low-dose aspirin had been approximately decreased of renal function damage. Kefir decreased renal function damage playing as Angiotensin-converting enzyme inhibitor. But, low-dose aspirin together with kefir worsened rat renal function damage. Cathepsin B might play role both apoptosis and prorenin-processing enzyme. But not caspase pathway may be involved in the present HS diet induced apoptosis. In conclusion, kefir and low-dose aspirin used independently protect renal function and renal damage induced by HS diet in rats.
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Tonomura Y, Morikawa Y, Takagi S, Torii M, Matsubara M. Underestimation of urinary biomarker-to-creatinine ratio resulting from age-related gain in muscle mass in rats. Toxicology 2013. [DOI: 10.1016/j.tox.2012.11.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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23
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van Koppen A, Joles JA, van Balkom BWM, Lim SK, de Kleijn D, Giles RH, Verhaar MC. Human embryonic mesenchymal stem cell-derived conditioned medium rescues kidney function in rats with established chronic kidney disease. PLoS One 2012; 7:e38746. [PMID: 22723882 PMCID: PMC3378606 DOI: 10.1371/journal.pone.0038746] [Citation(s) in RCA: 148] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 05/10/2012] [Indexed: 02/07/2023] Open
Abstract
Chronic kidney disease (CKD) is a major health care problem, affecting more than 35% of the elderly population worldwide. New interventions to slow or prevent disease progression are urgently needed. Beneficial effects of mesenchymal stem cells (MSC) have been described, however it is unclear whether the MSCs themselves or their secretome is required. We hypothesized that MSC-derived conditioned medium (CM) reduces progression of CKD and studied functional and structural effects in a rat model of established CKD. CKD was induced by 5/6 nephrectomy (SNX) combined with L-NNA and 6% NaCl diet in Lewis rats. Six weeks after SNX, CKD rats received either 50 µg CM or 50 µg non-CM (NCM) twice daily intravenously for four consecutive days. Six weeks after treatment CM administration was functionally effective: glomerular filtration rate (inulin clearance) and effective renal plasma flow (PAH clearance) were significantly higher in CM vs. NCM-treatment. Systolic blood pressure was lower in CM compared to NCM. Proteinuria tended to be lower after CM. Tubular and glomerular damage were reduced and more glomerular endothelial cells were found after CM. DNA damage repair was increased after CM. MSC-CM derived exosomes, tested in the same experimental setting, showed no protective effect on the kidney. In a rat model of established CKD, we demonstrated that administration of MSC-CM has a long-lasting therapeutic rescue function shown by decreased progression of CKD and reduced hypertension and glomerular injury.
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Affiliation(s)
- Arianne van Koppen
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Jaap A. Joles
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Bas W. M. van Balkom
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Sai Kiang Lim
- Institute of Medical Biology, A*STAR, Singapore, Republic of Singapore
| | - Dominique de Kleijn
- Department of Experimental Cardiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Rachel H. Giles
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Marianne C. Verhaar
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
- * E-mail:
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24
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Vallon V, Eraly SA, Rao SR, Gerasimova M, Rose M, Nagle M, Anzai N, Smith T, Sharma K, Nigam SK, Rieg T. A role for the organic anion transporter OAT3 in renal creatinine secretion in mice. Am J Physiol Renal Physiol 2012; 302:F1293-9. [PMID: 22338083 PMCID: PMC3362066 DOI: 10.1152/ajprenal.00013.2012] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 02/10/2012] [Indexed: 12/26/2022] Open
Abstract
Tubular secretion of the organic cation, creatinine, limits its value as a marker of glomerular filtration rate (GFR) but the molecular determinants of this pathway are unclear. The organic anion transporters, OAT1 and OAT3, are expressed on the basolateral membrane of the proximal tubule and transport organic anions but also neutral compounds and cations. Here, we demonstrate specific uptake of creatinine into mouse mOat1- and mOat3-microinjected Xenopus laevis oocytes at a concentration of 10 μM (i.e., similar to physiological plasma levels), which was inhibited by both probenecid and cimetidine, prototypical competitive inhibitors of organic anion and cation transporters, respectively. Renal creatinine clearance was consistently greater than inulin clearance (as a measure of GFR) in wild-type (WT) mice but not in mice lacking OAT1 (Oat1-/-) and OAT3 (Oat3-/-). WT mice presented renal creatinine net secretion (0.23 ± 0.03 μg/min) which represented 45 ± 6% of total renal creatinine excretion. Mean values for renal creatinine net secretion and renal creatinine secretion fraction were not different from zero in Oat1-/- (-0.03 ± 0.10 μg/min; -3 ± 18%) and Oat3-/- (0.01 ± 0.06 μg/min; -6 ± 19%), with greater variability in Oat1-/-. Expression of OAT3 protein in the renal membranes of Oat1-/- mice was reduced to ∼6% of WT levels, and that of OAT1 in Oat3-/- mice to ∼60%, possibly as a consequence of the genes for Oat1 and Oat3 having adjacent chromosomal locations. Plasma creatinine concentrations of Oat3-/- were elevated in clearance studies under anesthesia but not following brief isoflurane anesthesia, indicating that the former condition enhanced the quantitative contribution of OAT3 for renal creatinine secretion. The results are consistent with a contribution of OAT3 and possibly OAT1 to renal creatinine secretion in mice.
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Affiliation(s)
- Volker Vallon
- Depts. of Medicine and Pharmacology, Univ. of California San Diego and VASDHCS, 3350 La Jolla Village Dr. (9151 San Diego, CA 92161, USA.
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UCHIDA M, SAKAGUCHI Y, MIYAMOTO Y. A Novel Vitamin K 1 2,3-Epoxide Reductase (VKOR) Inhibitor, 3-Acetyl-5-Methyltetronic Acid, Reduces Experimental Glomerulonephritis. J Vet Med Sci 2012; 74:863-9. [DOI: 10.1292/jvms.11-0530] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Masashi UCHIDA
- Toxicology and Pharmacokinetics Laboratories, Pharmaceutical Research Laboratories, Toray Industries, Inc., 6–10–1 Tebiro, Kamakura, Kanagawa 248–8555, Japan
| | - Yuka SAKAGUCHI
- Toxicology and Pharmacokinetics Laboratories, Pharmaceutical Research Laboratories, Toray Industries, Inc., 6–10–1 Tebiro, Kamakura, Kanagawa 248–8555, Japan
| | - Yohei MIYAMOTO
- Toxicology and Pharmacokinetics Laboratories, Pharmaceutical Research Laboratories, Toray Industries, Inc., 6–10–1 Tebiro, Kamakura, Kanagawa 248–8555, Japan
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Estimation of glomerular filtration rate in calves using the contrast medium iodixanol. Vet J 2011; 193:174-9. [PMID: 22064323 DOI: 10.1016/j.tvjl.2011.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 10/02/2011] [Accepted: 10/04/2011] [Indexed: 11/23/2022]
Abstract
To develop a simple procedure for estimating glomerular filtration rate (GFR) in calves, a three-sample method using iodixanol was first compared to that using the standard agent inulin. Iodixanol and inulin were co-administered intravenously to calves at 40 mg I/kg and 40 mg/kg, respectively, and blood was collected 30, 60, 120, and 180 min later. Serum iodixanol and inulin concentrations were separately determined by high performance liquid chromatography and colorimetry. Serum urea nitrogen (UN) and creatinine concentrations were also measured. GFR estimated by iodixanol was consistent with that using inulin in clinically healthy calves. Based on GFR estimations in healthy calves and those renal-loaded with iodixanol, it was found that the serum creatinine concentrations became elevated when GFR decreased to 60% of the reference value. In contrast, serum UN concentrations fluctuated widely, presumably due to extra-renal factors. When GFR was estimated using the three-sample method and compared with the single-blood-sample method, 62/69 (90%) of samples tested were within the agreement plots. The results demonstrated that the single-blood-sample method using iodixanol may be useful in monitoring GFR in calves.
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Katayama R, Watanabe K, Yamagishi N, Abe S, Satoh H, Furuhama K. Sequential measurements of glomerular filtration rate in conscious rats by a bolus injection of iodixanol and a single blood sample. J Appl Toxicol 2010; 31:360-5. [DOI: 10.1002/jat.1619] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Rieko Katayama
- Department of Veterinary Basic Medicine; Iwate University; Morioka Iwate 020-8550 Japan
- United Graduate School of Veterinary Science; Gifu University; Gifu 501-1193 Japan
| | - Kanji Watanabe
- Department of Veterinary Basic Medicine; Iwate University; Morioka Iwate 020-8550 Japan
| | - Norio Yamagishi
- United Graduate School of Veterinary Science; Gifu University; Gifu 501-1193 Japan
- Department of Veterinary Clinical Medicine; Iwate University; Morioka Iwate 020-8550 Japan
| | - Sumito Abe
- Department of Veterinary Basic Medicine; Iwate University; Morioka Iwate 020-8550 Japan
| | - Hiroshi Satoh
- Shinwa BioCraft Laboratory Inc.; Edogawa-ku Tokyo 132-0013 Japan
| | - Kazuhisa Furuhama
- Department of Veterinary Basic Medicine; Iwate University; Morioka Iwate 020-8550 Japan
- United Graduate School of Veterinary Science; Gifu University; Gifu 501-1193 Japan
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Katayama R, Yamaguchi N, Yamashita T, Watanabe S, Satoh H, Yamagishi N, Furuhama K. Calculation of glomerular filtration rate in conscious rats by the use of a bolus injection of iodixanol and a single blood sample. J Pharmacol Toxicol Methods 2010; 61:59-64. [DOI: 10.1016/j.vascn.2009.10.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Revised: 10/06/2009] [Accepted: 10/06/2009] [Indexed: 10/20/2022]
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Eisner C, Faulhaber-Walter R, Wang Y, Leelahavanichkul A, Yuen PST, Mizel D, Star RA, Briggs JP, Levine M, Schnermann J. Major contribution of tubular secretion to creatinine clearance in mice. Kidney Int 2009; 77:519-26. [PMID: 20032962 DOI: 10.1038/ki.2009.501] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This study was performed to quantify the fraction of excreted creatinine not attributable to creatinine filtration for accurately determining the glomerular filtration rate in mice. To measure this we compared creatinine filtration with the simultaneous measurement of inulin clearance using both single-bolus fluorescein isothiocyanate (FITC)-inulin elimination kinetics and standard FITC-inulin infusion. During anesthesia, creatinine filtration was found to be systematically higher than inulin clearance in both male and female C57BL/6J mice. The secretion fraction was significantly less in female mice. Administration of either cimetidine or para-aminohippuric acid, competitors of organic cation and anion transport respectively, significantly reduced the secretion fraction in male and female mice and both significantly increased the plasma creatinine level. Creatinine secretion in both genders was not mediated by the organic cation transporters OCT1 or OCT 2 since secretion fraction levels were identical in FVB wild-type and OCT1/2 knockout mice. Thus, secretion accounts for about 50 and 35% of excreted creatinine in male and female mice, respectively. Increasing plasma creatinine threefold by infusion further increased the secretion fraction. Renal organic anion transporter 1 mRNA expression was higher in male than in female mice, reflecting the gender difference in creatinine secretion. Hence we show that there is a major secretory contribution to creatinine excretion mediated through the organic anion transport system. This feature adds to problems associated with measuring endogenous creatinine filtration in mice.
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Affiliation(s)
- Christoph Eisner
- National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland 20892, USA
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Wang Q, Wang X, Morris ME. Effects of L-lactate and D-mannitol on gamma-hydroxybutyrate toxicokinetics and toxicodynamics in rats. Drug Metab Dispos 2008; 36:2244-51. [PMID: 18719239 DOI: 10.1124/dmd.108.022996] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Overdoses of gamma-hydroxybutyrate (GHB), a drug of abuse, result in coma, respiratory arrest, and death. The objective of this study was to evaluate a potential GHB detoxification strategy by inhibiting the monocarboxylate transporter (MCT)-mediated renal reabsorption of GHB in rats, using the MCT substrate L-lactate. The use of the osmotic diuretic D-mannitol alone or combined with L-lactate was also explored. GHB (208 mg/h/kg) was infused i.v. for 3 h in the absence or presence of L-lactate (60.5, 121, and 302.5 mg h(-1) kg(-1)), D-mannitol (0.5 g/kg), or L-lactate (60.5 mg h(-1) kg(-1)) combined with D-mannitol (0.5 g/kg). GHB in plasma and urine samples was determined along with blood pH, electrolytes, glucose, and L-lactate. Administration of L-lactate, or the combination of L-lactate and D-mannitol, but not D-mannitol alone, significantly increased the renal and total clearances of GHB in rats. Blood pH and electrolyte concentrations exhibited small changes with GHB, GHB/lactate, and GHB/mannitol treatments, although most values remained within their normal range. The concomitant administration of lactated Ringer's solution (28 mM L-lactate) at 300 mul/min with mannitol (0.5 g/kg) resulted in a significant increase in GHB clearance and a decrease in sleep time after an i.v. dose of 1 g/kg. Overall, our results indicated the following: 1) the use of the MCT inhibitor L-lactate can increase the renal and total clearances of GHB, and 2) the combination of lactated Ringer's solution and D-mannitol significantly alters GHB toxicokinetics and toxicodynamics and represents a potential clinical detoxification strategy for the treatment of GHB overdoses.
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Affiliation(s)
- Qi Wang
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, State University of New York, Amherst, NY 14260, USA
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31
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Schnöckel U, Reuter S, Stegger L, Schlatter E, Schäfers KP, Hermann S, Schober O, Gabriëls G, Schäfers M. Dynamic 18F-fluoride small animal PET to noninvasively assess renal function in rats. Eur J Nucl Med Mol Imaging 2008; 35:2267-74. [PMID: 18622612 DOI: 10.1007/s00259-008-0878-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Accepted: 06/23/2008] [Indexed: 12/23/2022]
Abstract
PURPOSE Renal function can be quantified by both laboratory and scintigraphic methods. In the case of small animal diagnostics, scintigraphic image-based methods are ideal since they can assess split renal function, work noninvasively, and can be repeated. The aim of this study is to validate a (18)F-PET-based method to quantify renal function in rats. MATERIALS AND METHODS Fluoride clearance was calculated from a dynamic whole body listmode acquisition of 60 min length in a small animal PET scanner following an i.v. injection of 15 MBq (18)F-fluoride. Volumes of interest (VOIs) were placed in the left ventricle and the bladder as well as traced around the kidney contours. The respective time-activity curves (TAC) were calculated. The renal (18)F-clearance was calculated by the ratio of the total renal excreted activity (bladder VOI) and the integral of the blood TAC. PET-derived renal function was validated by intraindividual measurements of creatinine clearance (n = 23), urea clearance (n = 23), and tubular excretion rate (TER-MAG3). The split renal function was derived from the injection of the clinically available radionuclide (99m)Tc-mercaptotriglycine by blood sampling and planar renography (n = 8). RESULTS In all animals studied, PET revealed high-quality TACs. PET-derived renal fluoride clearance was linearly correlated with intraindividual laboratory measures (PET vs. creatinine: r = 0.78; PET vs. urea: r = 0.73; PET vs. TER-MAG3: r = 0.73). Split function was comparable ((18)F-PET vs. MAG3-renography: r = 0.98). PET-derived measures were highly reproducible. CONCLUSIONS (18)F-PET is able to noninvasively assess renal function in rats and provides a significant potential for serial studies in different experimental scenarios.
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Affiliation(s)
- Uta Schnöckel
- Klinik und Poliklinik für Nuklearmedizin, 48149 Münster, Germany.
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Minematsu T, Hashimoto T, Aoki T, Usui T, Kamimura H. Role of Organic Anion Transporters in the Pharmacokinetics of Zonampanel, an α-Amino-3-hydroxy-5-methylisoxazole-4-propionate Receptor Antagonist, in Rats. Drug Metab Dispos 2008; 36:1496-504. [DOI: 10.1124/dmd.107.019828] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Chamberlain RM, Shirley DG. Time course of the renal functional response to partial nephrectomy: measurements in conscious rats. Exp Physiol 2007; 92:251-62. [PMID: 17085677 DOI: 10.1113/expphysiol.2006.034751] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Previous investigations into the functional responses of the surviving nephrons following reductions in renal mass have been performed largely in anaesthetized animals and have taken little account of how the compensatory changes develop with time. The present study has assessed a method for determining glomerular filtration rate (GFR) in unrestrained, uncatheterized, conscious rats (plasma disappearance of (99m)Tc-diethylenetriamene pentaacetic acid (DTPA)) and has used this method to document the time course of the changes in GFR over a 32 day period following uninephrectomy or 5/6 nephrectomy. Concurrent measurements of excretion rates and of the clearance of lithium (the latter being an index of end-proximal fluid delivery) provided information on changes in overall tubular function and segmental reabsorption. After uninephrectomy, the GFR of the remaining kidney (compared with that of a single kidney of sham-operated animals) increased maximally (by approximately 50%) within 8 days; after 5/6 nephrectomy, the increase in the GFR of the remnant kidney was maximal (at approximately 300%) within 16 days. Overall excretion rates of sodium and potassium were well maintained in partially nephrectomized animals throughout the period of study, while the excretion of water increased (by approximately 30% after uninephrectomy and by approximately 120% after 5/6 nephrectomy), partly as a result of the compensatory increases in GFR but mainly as a consequence of moderate (after uninephrectomy) or marked (after 5/6 nephrectomy) reductions in fractional reabsorption. During the early period after 5/6 nephrectomy, potassium excretion sometimes exceeded the filtered load, indicating net secretion. Lithium clearance data indicated that the changes in tubular function after 5/6 nephrectomy include a reduction in fractional reabsorption in the proximal tubule, whereas after uninephrectomy any such effect on the proximal tubule is minor and transient.
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Affiliation(s)
- R M Chamberlain
- Department of Physiology and Centre for Nephrology, Royal Free & University College School of Medicine, Hampstead Campus, Rowland Hill Street, London NW3 2PF, UK
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Aliabadi HM, Spencer TJ, Mahdipoor P, Lavasanifar A, Brocks DR. Insights into the effects of hyperlipoproteinemia on cyclosporine A biodistribution and relationship to renal function. AAPS JOURNAL 2006; 8:E672-81. [PMID: 17233531 PMCID: PMC2751364 DOI: 10.1208/aapsj080477] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The purpose of this study was to assess the effect of hyperlipoproteinemia on the biodistribution of cyclosporine A (CyA), an extensively lipoprotein bound immunosuppressant, in a rat model and to determine the potential toxicological significance of this effect. Normolipidemic and hyperlipoproteinemic rats were given a single 5 mg/kg dose of CyA as intravenous bolus and at selected times postdose, tissues, blood, and plasma were harvested and assayed for CyA content. Hyperlipoproteinemia was induced by intraperitoneal injection of 1 g/kg poloxamer 407. Compared with normolipidemic animals, hyperlipoproteinemic rats had higher plasma, blood, kidney, and liver CyA concentrations. In contrast, in heart and spleen the concentrations were decreased in hyperlipoproteinemia. The nephrotoxic effect of CyA was also evaluated in normolipidemic and hyperlipoproteinemic rats after 7 days of dosing with 20 mg/kg/day. In both groups of animals, repeated doses of CyA were associated with equivalent decreases in creatinine and urea clearances compared with matching control and predose baseline measures. The concentrations of drug in kidney were equivalent at the conclusion of the study. However, despite these similarities there was microscopic evidence of more severe changes in the kidneys in the hyperlipoproteinemic rats, which also experienced a significant decrease in body weight compared with the normolipedemic animals. In conclusion, the distribution of CyA to kidneys was enhanced in poloxamer 407-induced hyperlipoproteinemic rats after single doses, and with repeated doses there was an apparent greater adverse effect on these animals compared with normolipidemic animals.
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Affiliation(s)
- Hamidreza Montazeri Aliabadi
- 3126 Dentistry-Pharmacy Centre, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta
| | - Tara J. Spencer
- 3126 Dentistry-Pharmacy Centre, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta
| | - Parvin Mahdipoor
- 3126 Dentistry-Pharmacy Centre, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta
| | - Afsaneh Lavasanifar
- 3126 Dentistry-Pharmacy Centre, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta
| | - Dion R. Brocks
- 3126 Dentistry-Pharmacy Centre, Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta
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Pérez-Rojas JM, Blanco JA, Gamba G, Bobadilla NA. Low calorie commercial sugar is a sensitive marker of glomerular filtration rate. Kidney Int 2005; 68:1888-93. [PMID: 16164668 DOI: 10.1111/j.1523-1755.2005.00609.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Glomerular filtration rate (GFR) in humans and animals might be determined with precision by measuring the clearance of an ideal marker, such as inulin. However, the use of inutest, an inulin analog, is limited by its cost and accessibility. The present study tested whether low calorie commercial sugar (LC sugar) can be used to measure GFR during normal and renal dysfunction. METHODS Two groups of 6 male Wistar rats weighing 300 to 350 g were included. One group was treated with a daily dose of cyclosporine (CsA) 30 mg/kg subcutaneously for 7 days and the other group was formed by nontreated control rats. In one half of each group, GFR was evaluated by using inutest and in the other half by using LC sugar. GFR was also evaluated by using a wide LC sugar plasma concentration range in an additional group. RESULTS In nontreated rats, the mean GFR evaluated with LC sugar was 2.2 +/- 0.1 mL/min. This value is equal to that obtained with inutest: 2.3 +/- 0.1 mL/min. CsA administration produced a significant reduction of renal blood flow and renal function. The GFR reduction induced by CsA was similarly determined by both LC sugar and inutest to be at 1.0 +/- 0.2 and 1.1 +/- 0.2 mL/min (P= NS), respectively. In addition, GFR did not change when LC sugar plasma concentration gradually increased. CONCLUSION Our results show that in both normal and pathophysiologic conditions, LC sugar is a good marker of GFR similar to the gold standard inutest.
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Affiliation(s)
- Jazmin M Pérez-Rojas
- Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México
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Thomas MC, Jerums G, Tsalamandris C, Macisaac R, Panagiotopoulos S, Cooper ME. Increased tubular organic ion clearance following chronic ACE inhibition in patients with type 1 diabetes. Kidney Int 2005; 67:2494-9. [PMID: 15882297 DOI: 10.1111/j.1523-1755.2005.00359.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The tubular excretion of creatinine significantly contributes to its clearance. Administration of an angtiotensin-converting enzyme (ACE) inhibitor is associated with increased organic ion clearance in experimental diabetes. This study examines the effect and implications of chronic ACE inhibition on renal organic ion excretion in patients with type 1 diabetes. METHODS Samples were obtained from the Melbourne Diabetic Nephropathy Study Group (MDNSG) that randomized patients to receive perindopril (N= 11), nifedipine (N= 11), or placebo (N= 8). Albumin excretion rate, creatinine clearance, and isotopic glomerular filtration rate (GFR) were assessed at baseline and after 24 months. In addition, the clearance of the endogenous cations N-methylynicotinamide (NMN), creatinine, and the anion hippurate were determined by high-performance liquid chromatography (HPLC). RESULTS Following treatment with the ACE inhibitor, perindopril, renal clearance of NMN was increased (+96%) (P < 0.05). There was no difference in patients treated with nifedipine (P= 0.25) and NMN clearance fell in the placebo-treated patients (-26%) (P < 0.05). Changes in NMN clearance were unaffected after adjusting for the effects of perindopril on GFR. However, they were attenuated after adjusting for hippurate clearance, a marker of renal blood flow. This effect of perindopril on NMN clearance was seen in both men and women, regardless of baseline clearance and was correlated with reduced albuminuria following perindopril treatment. CONCLUSION Organic ion clearance is increased in patients with diabetes following chronic ACE inhibition. This is consistent with experimental models showing increased ion transporter expression and improved tubular blood flow, following blockade of the renin-angiotensin system (RAS). These findings may have implications for the interpretation of creatinine-based indices in patients with diabetes.
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Affiliation(s)
- Merlin C Thomas
- Baker Medical Research Institute, Melbourne, Victoria, Australia.
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Morris ME, Hu K, Wang Q. Renal clearance of gamma-hydroxybutyric acid in rats: increasing renal elimination as a detoxification strategy. J Pharmacol Exp Ther 2005; 313:1194-202. [PMID: 15722403 DOI: 10.1124/jpet.105.083253] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Intoxication with gamma-hydroxybutyric acid (GHB) is associated with coma, seizure, and death; treatment of overdoses is symptomatic. The objectives of this investigation were to characterize the renal clearance and total clearance of GHB in rats and to evaluate potential strategies for increasing the elimination of GHB after drug overdoses. GHB was administered by i.v. infusion at low (108 mg/h/kg), medium (128 mg/h/kg), or high (208 mg/h/kg) doses. Crossover studies were performed under steady-state conditions using the medium dose in the absence or presence of l-lactate, pyruvate, d-mannitol, sodium bicarbonate, or normal saline. GHB in plasma and urine samples was assayed using liquid chromatography-tandem mass spectrometry. Infusion of the low, medium, and high doses of GHB produced steady-state plasma concentrations of 0.22 +/- 0.04, 0.43 +/- 0.05, and 0.68 +/- 0.11 mg/ml. The renal clearance of the medium (51.8 +/- 13.0 ml/h/kg) and high (97.1 +/- 43.1 ml/h/kg) doses was significantly higher than that of the low dose (14.9 +/- 5.1 ml/h/kg), whereas the total clearance values were significantly lower than that of the low dose. The renal clearance was significantly increased by the concomitant administration of l-lactate, pyruvate, d-mannitol, or sodium bicarbonate with GHB but was not altered by normal saline. The total and metabolic clearance values were significantly increased by all treatments except normal saline. Overall, our results indicated that the renal clearance of GHB is dose-dependent, involving capacity-limited reabsorption. Monocarboxylate transport inhibitors, osmotic diuresis using d-mannitol, or the administration of sodium bicarbonate can increase the renal and total clearances of GHB. The approaches used in this investigation may offer potential detoxification strategies for the treatment of GHB overdoses.
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Affiliation(s)
- Marilyn E Morris
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, State University of New York, Amherst, 14260, USA.
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Sagawa K, Murer H, Morris ME. Effect of experimentally induced hypothyroidism on sulfate renal transport in rats. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:F164-71. [PMID: 9887092 DOI: 10.1152/ajprenal.1999.276.1.f164] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Decreased serum sulfate concentrations are observed in hypothyroid patients. However, the mechanism involved in thyroid hormone-induced alterations of renal sulfate homeostasis is unknown. The objectives of this investigation were to determine the effect of 6-propyl-2-thiouracil (PTU)-induced hypothyroidism in rats on 1) the in vivo serum concentrations, renal clearance, and renal reabsorption of sulfate, 2) the in vitro renal transport in brush-border membrane (BBM) and basolateral membrane (BLM) vesicles, and 3) the cellular mechanism of the hypothyroid-induced alteration in sulfate renal transport. Serum sulfate concentrations, renal fractional reabsorption of sulfate, and creatinine clearance were decreased significantly in the hypothyroid group. The Vmax values for sodium-sulfate cotransport in BBM were significantly decreased in the kidney cortex from the hypothyroid animals (0.90 +/- 0.31 vs. 0.49 +/- 0.08 nmol. mg-1. 10 s-1, n = 5-6, P < 0.05) without changes in Km. There were no significant differences in Vmax and Km for sulfate/anion exchange transport in BLM. Sodium-dependent sulfate transporter (NaSi-1) mRNA and protein levels were significantly lower in the kidney cortex from hypothyroid rats. Hypothyroidism did not alter the membrane motional order (fluidity) in BBM and BLM, which indicates that the changes in the membrane fluidity do not represent the mechanism for the altered renal transport. These results demonstrate that PTU-induced hypothyroidism decreases sodium-sulfate cotransport by downregulation of the NaSi-1 gene.
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Affiliation(s)
- K Sagawa
- Department of Pharmaceutics, State University of New York at Buffalo, Amherst, New York 14260, USA
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Kusama M, Yamamoto K, Yamada H, Kotaki H, Sato H, Iga T. Effect of cilastatin on renal handling of vancomycin in rats. J Pharm Sci 1998; 87:1173-6. [PMID: 9724573 DOI: 10.1021/js9801135] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
To provide insights into the possibility of reducing the nephrotoxicity of vancomycin (VCM) by cilastatin, the effect of cilastatin on the renal handling of VCM, as well as on glomerular filtration rate (GFR) and plasma protein binding of VCM, were studied using rats. After a bolus intravenous (iv) dose of VCM (100 mg/kg), concomitant cilastatin administration (100 mg/kg, iv) resulted in a significant increase in the total VCM clearance and significant decrease in the kidney uptake clearance of VCM, defined as kidney VCM concentration vs AUC ratio. Moreover, after a 3-h continuous iv infusion of VCM (18 or 90 mg/h/kg), significant decrease in the kidney uptake clearance of VCM was observed with concomitant cilastatin iv infusion (300 mg/h/kg). On the other hand, GFR and VCM plasma protein binding did not show any significant change with cilastatin. From the observation that cilastatin decreased the kidney uptake clearance of VCM and enhanced its urinary excretion, it was suggested that cilastatin inhibited the reabsorption of VCM in the renal proximal tubular cells. Thus, it may be possible that cilastatin alleviates the nephrotoxicity of VCM due to reduced accumulation and accelerated renal excretion of VCM.
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Affiliation(s)
- M Kusama
- Department of Pharmacy, University of Tokyo Hospital, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
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Foote EF, Halstenson CE. Effects of probenecid and cimetidine on renal disposition of ofloxacin in rats. Antimicrob Agents Chemother 1998; 42:456-8. [PMID: 9527807 PMCID: PMC105435 DOI: 10.1128/aac.42.2.456] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The renal handling of ofloxacin in rats which were given ofloxacin either alone or in combination with probenecid or cimetidine was studied. In the presence of cimetidine or probenecid, ofloxacin's total and renal clearances were reduced and its half-life was prolonged. This suggests that ofloxacin is secreted by both the anionic and cationic transport systems.
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Affiliation(s)
- E F Foote
- Department of Medicine, Hennepin County Medical Center, and College of Pharmacy, University of Minnesota, Minneapolis 55455, USA.
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Knopp D. Assessment of exposure to 2,4-dichlorophenoxyacetic acid in the chemical industry: results of a five year biological monitoring study. Occup Environ Med 1994; 51:152-9. [PMID: 8130842 PMCID: PMC1127932 DOI: 10.1136/oem.51.3.152] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Data on individual exposure to 2,4-dichlorophenoxyacetic acid (2,4-D) in herbicide production plants are limited. Hence, the urinary excretion of this herbicide was measured during a five year (1985-1989) biological monitoring study of 27 men and 18 women employees exposed during the production and formulation of 2,4-D and related sodium and dimethylamine salts. In separate studies, specimens of urine were collected in the morning, or during the last three hours of a working shift, or over a 24 hour period (1200 to 1200 or 0800 to 0800) and were analysed by an immunochemical method (2,4-D radioimmunoassay (RIA)). Urinary 2,4-D concentrations varied within a large scale from only a few micrograms/l to several 10s of mg/l. During a week, herbicide excretion increased, culminating on Friday. At the weekend, when no work was done, 2,4-D elimination decreased but did not return to zero in any case. After an interruption of exposure for about three weeks, urinary 2,4-D was no longer detectable. About five days after restarting work, body concentrations had built up again. Measurements of 2,4-D concentrations in air at different work-places showed that herbicide concentrations did not exceed 0.5 mg/m3. As well as inhalation, dermal 2,4-D absorption seemed to play an important part in total uptake of herbicide. Furthermore, a strong correlation was found (r = 0.9628) between 2,4-D urinary concentration, adjusted for endogenous creatinine, and the estimated amount of absorbed herbicide. Estimated absorbed doses were, in most cases, well below 0.1 mg 2,4-D/kg body wt/day. Sometimes this concentration was greatly exceeded. Thyroid hormone concentrations in blood were measured as well. No notable abnormalities were found. Exposed subjects were also typed for histocompatibility locus antigens (ABC antigens). The immunochemical determination of 2,4-D in specimens of urine proved to be a simple, cost effective, and non-invasive method to measure human exposure.
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Affiliation(s)
- D Knopp
- Institute of Hydrochemistry and Chemical Balneology, Technical University Munich, Germany
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Abstract
A 2 mg kg-1 intravenous bolus dose of digoxin-specific Fab fragments produced a 28% reduction in creatinine clearance in rabbits after 24 h. Urine output was reduced, while plasma and urinary creatinine concentrations were unaffected and increased, respectively. By 5 days the creatinine clearance had returned to normal. The fractional excretion of Na+ was nearly halved, indicating that the tubular reabsorption of Na+ increased to compensate for the reduced glomerular filtration rate, suggesting that tubular (as opposed to glomerular) function was not impaired.
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Affiliation(s)
- M P Timsina
- Department of Pharmacology and Clinical Pharmacology, University of Dundee, Ninewells Hospital and Medical School, UK
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Bakhtian S, Kimura RE, Galinsky RE. Age-related changes in homeostasis of inorganic sulfate in male F-344 rats. Mech Ageing Dev 1993; 66:257-67. [PMID: 8469018 DOI: 10.1016/0047-6374(93)90013-h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Advanced age is associated with a decline in renal function including decreased glomerular filtration rate, renal blood flow and renal tubular secretion. Endogenous inorganic sulfate homeostasis is maintained by concentration-dependent active renal reabsorption in the proximal tubule. The purpose of this study was to determine the effects of advanced age on: (1) the renal mechanisms for conserving endogenous inorganic sulfate and (2) the turnover of inorganic sulfate. Awake, male Fischer 344 rats age 4-5 months and 22-23 months received i.v. acetaminophen, 300 mg/kg, followed 2 h later by i.v. sodium sulfate, 2 mmol/kg, to lower and raise, respectively, plasma inorganic sulfate in order to measure the renal clearance of this anion from plasma at sub- and supraphysiologic concentration ranges. Another group of old and young male F-344 rats received a tracer injection of [35S]sodium sulfate to determine the effect of aging on the turnover of the endogenous inorganic sulfate pool. There was no statistically significant effect of advanced age on baseline plasma sulfate concentration or on the renal clearance of inorganic sulfate from plasma. The baseline excretion rate of inorganic sulfate in the senescent animals (0.38 +/- 0.25 mumol/min/kg, mean +/- S.D., n = 7) was significantly (P < 0.05) lower than that observed in the young animals (0.64 +/- 0.19 mumol/min/kg, n = 8). There was no difference in the turnover rate constant, as measured by the change in specific activity of urinary [35S]sodium sulfate, for the endogenous sulfate pool in old and young animals. Following acetaminophen administration, plasma sulfate concentrations declined similarly in young and old animals. Under the conditions of relative inorganic sulfate depletion, the renal excretion rate of inorganic sulfate decreased to zero in 7 of 8 young rats, whereas the old animals continued to excrete sulfate anion at an average rate of 23% of the baseline value. Aged animals have a defect in active tubular renal reabsorption of sulfate under conditions of sulfate depletion. Age-related changes in the total sulfate excretion rate may reflect changes in the metabolic fate of endogenous sulfate rather than changes in the endogenous production rate of this anion.
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Affiliation(s)
- S Bakhtian
- Department of Pharmaceutics, College of Pharmacy, University of Utah, Salt Lake City 84112
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