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Li K, Wang B, Yan L, Jin Y, Li Z, An H, Ren M, Pang Y, Lan C, Chen J, Zhang Y, Zhang L, Ye R, Li Z, Ren A. Associations between blood heavy metal(loid)s and serum heme oxygenase-1 in pregnant women: Do their distribution patterns matter? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 286:117249. [PMID: 33975215 DOI: 10.1016/j.envpol.2021.117249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 04/21/2021] [Accepted: 04/24/2021] [Indexed: 06/12/2023]
Abstract
The relationship between heavy metal(loid)s exposure and oxidative stress damage is a matter of research interest. Our study aimed to investigate the distribution patterns of the nine heavy metal(loid)s in blood of pregnant women, including four toxic heavy metal(loid)s [arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg)] and five typical heavy metal(loid)s [manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn), and selenium (Se)] in blood. Blood samples of 348 women were collected and their concentrations in the serum (sr) and blood cells (bc) were measured, as well as serum heme oxygenase-1 (HO-1) (an oxidative stress marker). Total blood (tb) concentrations of these metal(loid)s and serum-to-blood cell concentration ratios (sr/bc) were further calculated. We found Cu mainly accumulated in the serum compared to the blood cells with Cusr/bc = 2.30, whereas Co, Se, and As evenly distributed between these two fractions. Other metal(loid)s mainly concentrated in the blood cells. Cosr, Cusr, Cubc, Mnbc, Znbc, Cdbc, Cotb, Cutb, Mntb, Zntb, Cdtb, and Cusr/bc were negatively associated with serum HO-1, whereas Assr, Asbc, Astb, Znsr/bc, Cdsr/bc, and Hgsr/bc were positively, indicating of their potential toxicity. We concluded that the distribution patterns of blood heavy metal(loid)s, in particular for Cd, Hg and Zn, which either increased in serum or decreased in blood cells, might be associated with elevated serum oxidative stress, should be considered in environmental health assessments.
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Affiliation(s)
- Kexin Li
- Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, 100101, PR China
| | - Bin Wang
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China.
| | - Lailai Yan
- Department of Laboratorial Science and Technology, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Yu Jin
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Zhiyi Li
- Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, 100101, PR China
| | - Hang An
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Mengyuan Ren
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Yiming Pang
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Changxin Lan
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Junxi Chen
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Yali Zhang
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Le Zhang
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Rongwei Ye
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Zhiwen Li
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Aiguo Ren
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
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An H, Wang B, Li Z, Jin Y, Ren M, Yu Y, Zhang Y, Zhang L, Yan L, Li Z, Ren A, Ye R, Li K. Distribution of mercury in serum and blood cells and risk of spontaneous preterm birth: A nested case-control study in China. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 217:112228. [PMID: 33892343 DOI: 10.1016/j.ecoenv.2021.112228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 06/12/2023]
Abstract
The relationship between maternal mercury (Hg) intake and the risk of spontaneous preterm birth (SPB) remains unclear. We conducted a nested case-control study from a prospective cohort in Shanxi Province, China, to explore their associations. In total, 126 pregnant women with SPB (cases) and 348 controls with term delivery were included. We measured the Hg concentrations in their serum (Hgs) and blood cell (Hgc) fractions and calculated the concentration ratio of Hg in serum to Hg in blood cells (Hgs/c). We found that only the Hgs/c in the case group was slightly higher than that in control group. The OR of Hgs/c associated with SPB risk was 1.57 [95%CI: 0.99-2.46] with adjusting confounders. After stratification by sampling time, the association above was only statistically significant in the first trimester. High Hgs/c may increase the risk of SPB in the first trimester among women with relatively low Hg exposure.
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Affiliation(s)
- Hang An
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Bin Wang
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Zhiyi Li
- Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, PR China
| | - Yu Jin
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Mengyuan Ren
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Yanxin Yu
- School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Yali Zhang
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Le Zhang
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Lailai Yan
- Department of Laboratorial Science and Technology, School of Public Health, Peking University, Beijing 100191, PR China
| | - Zhiwen Li
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Aiguo Ren
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China
| | - Rongwei Ye
- Institute of Reproductive and Child Health, Peking University, Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, PR China.
| | - Kexin Li
- Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, PR China.
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Nogara PA, Oliveira CS, Schmitz GL, Piquini PC, Farina M, Aschner M, Rocha JBT. Methylmercury's chemistry: From the environment to the mammalian brain. Biochim Biophys Acta Gen Subj 2019; 1863:129284. [PMID: 30659885 DOI: 10.1016/j.bbagen.2019.01.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 12/14/2018] [Accepted: 01/09/2019] [Indexed: 02/06/2023]
Abstract
Methylmercury is a neurotoxicant that is found in fish and rice. MeHg's toxicity is mediated by blockage of -SH and -SeH groups of proteins. However, the identification of MeHg's targets is elusive. Here we focus on the chemistry of MeHg in the abiotic and biotic environment. The toxicological chemistry of MeHg is complex in metazoans, but at the atomic level it can be explained by exchange reactions of MeHg bound to -S(e)H with another free -S(e)H group (R1S(e)-HgMe + R2-S(e)H ↔ R1S(e)H + R2-S(e)-HgMe). This reaction was first studied by professor Rabenstein and here it is referred as the "Rabenstein's Reaction". The absorption, distribution, and excretion of MeHg in the environment and in the body of animals will be dictated by Rabenstein's reactions. The affinity of MeHg by thiol and selenol groups and the exchange of MeHg by Rabenstein's Reaction (which is a diffusion controlled reaction) dictates MeHg's neurotoxicity. However, it is important to emphasize that the MeHg exchange reaction velocity with different types of thiol- and selenol-containing proteins will also depend on protein-specific structural and thermodynamical factors. New experimental approaches and detailed studies about the Rabenstein's reaction between MeHg with low molecular mass thiol (LMM-SH) molecules (cysteine, GSH, acetyl-CoA, lipoate, homocysteine) with abundant high molecular mass thiol (HMM-SH) molecules (albumin, hemoglobin) and HMM-SeH (GPxs, Selenoprotein P, TrxR1-3) are needed. The study of MeHg migration from -S(e)-Hg- bonds to free -S(e)H groups (Rabenstein's Reaction) in pure chemical systems and neural cells (with special emphasis to the LMM-SH and HMM-S(e)H molecules cited above) will be critical to developing realistic constants to be used in silico models that will predict the distribution of MeHg in humans.
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Affiliation(s)
- Pablo A Nogara
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Cláudia S Oliveira
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Gabriela L Schmitz
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Paulo C Piquini
- Departamento de Física, CCNE, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Marcelo Farina
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - João B T Rocha
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
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Heggland I, Kaur P, Syversen T. Uptake and efflux of methylmercury in vitro: Comparison of transport mechanisms in C6, B35 and RBE4 cells. Toxicol In Vitro 2009; 23:1020-7. [DOI: 10.1016/j.tiv.2009.06.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 06/10/2009] [Accepted: 06/15/2009] [Indexed: 10/20/2022]
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Leaner JJ, Mason RP. Methylmercury accumulation and fluxes across the intestine of channel catfish, Ictalurus punctatus. Comp Biochem Physiol C Toxicol Pharmacol 2002; 132:247-59. [PMID: 12106901 DOI: 10.1016/s1532-0456(02)00072-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The excised intestines of channel catfish, Ictalurus punctatus, were perfused at 20 or 4 degrees C for 1 h 45 min, with methylmercury (CH(3)HgCl) alone, or in the presence of excess L-cysteine (L-Cys), D-cysteine (D-Cys), L-methionine (L-Met); or with ouabain or probenecid to identify the potential CH(3)Hg(II) uptake pathways in fish intestines. A temperature effect was noted, with CH(3)Hg(II) concentrations in tissues perfused at 20 degrees C being higher than at 4 degrees C, substantiating the idea that mechanisms requiring metabolic energy are involved in CH(3)Hg(II) uptake in fish intestines. The results indicate that, when CH(3)Hg(II) is complexed as the CH(3)Hg-L-Cys complex, it is taken up via an L-neutral amino acid carrier and rapidly transported to the serosal side of the intestine. Methylmercury uptake could be inhibited by probenecid and ouabain, although probenecid had less impact on CH(3)Hg(II) uptake than ouabain. Our results for CH(3)Hg(II) uptake in the presence of D-Cys, L-Met in excess of L-Cys, or with a metal mixture further established that CH(3)Hg(II) uptake across fish intestines occurs via a variety of pathways, including an energy-dependent L-neutral amino acid carrier, and that the route and amount of accumulation were a function of CH(3)Hg(II) speciation in the digestive tract of the fish.
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Affiliation(s)
- Joy J Leaner
- University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, P.O. Box 38, Solomons, MD 20688, USA
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Andres S, Laporte JM, Mason RP. Mercury accumulation and flux across the gills and the intestine of the blue crab (Callinectes sapidus). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2002; 56:303-320. [PMID: 11856578 DOI: 10.1016/s0166-445x(01)00228-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper details the results of perfusion experiments examining the accumulation of inorganic and methylmercury (Hg and MMHg) into the gill and intestine tissue of the blue crab, Callinectes sapidus. Additionally, the flux across the tissue to an internal medium, representative of crab tissue or haemolymph, during the perfusion was also measured. The accumulation and transfer processes were studied for each form by exposing the organs to a wide range of Hg and MMHg water concentrations, as well as a mixture of the two Hg forms. Experiments were also performed at different temperatures and in the presence of a metabolic inhibitor to assess the accumulation mechanisms. While the Hg levels bioaccumulated in the two organs were of the same order, the fluxes of Hg from the tissue to the internal medium were slightly higher in the intestine than in the gill. At low external concentrations, the uptake was very similar for both Hg forms, but as exposure pressure increased, inorganic Hg uptake slowed whereas MMHg uptake increased linearly. The results from the perfusion experiments with a mixture of inorganic Hg and MMHg show that while these two forms of Hg do share common uptake pathways, there is also independent uptake. The temperature and inhibition experiments with ouabain, a Na(+)K(+)ATPase inhibitor, show that accumulation is at least partially energy dependent. Overall, the results suggest that there is more than one mechanism of accumulation for both Hg forms. Finally, as accumulation of Hg and MMHg into these tissues was similar, these results contrast with the literature assertion that the enhanced bioaccumulation of MMHg over inorganic Hg is a result of MMHg being more readily transported across the gut membrane.
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Affiliation(s)
- Sandrine Andres
- University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, P.O. Box 38, Solomons, MD 20688, USA
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Laporte JM, Andres S, Mason RP. Effect of ligands and other metals on the uptake of mercury and methylmercury across the gills and the intestine of the blue crab (Callinectes sapidus). Comp Biochem Physiol C Toxicol Pharmacol 2002; 131:185-96. [PMID: 11879786 DOI: 10.1016/s1532-0456(01)00289-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Using the perfusion method, we compared the accumulation and flux of inorganic mercury (Hg) and methylmercury (CH(3)Hg) across the gills and intestine of the blue crab, Callinectes sapidus. The accumulation and transfer processes were studied for each form by exposing the organs in the presence of specific ligands and other metals. While binding of Hg and CH(3)Hg to organic ligands reduced the rate of uptake in most instances, the differences in accumulation could not be explained only in terms of passive diffusive uptake. Thus, it appears that Hg and CH(3)Hg accumulation is dominated by ligand exchange or facilitated transport processes. Exposure of the gills and intestine in the presence of a suite of metals and metalloids showed that inorganic Hg and CH(3)Hg uptake was largely by different mechanisms to that of the other elements, as there was little interaction in terms of uptake rate. Overall, the results of this study suggest that inorganic Hg and CH(3)Hg uptake into the gills and intestine of this invertebrate is by a variety of pathways, both active and passive.
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Affiliation(s)
- Jean-Michel Laporte
- University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, P.O. Box 38, Solomons, MD 20688, USA
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Endo T, Kimura O, Sakata M, Shaikh ZA. Mercury uptake by LLC-PK1 cells: dependence on temperature and membrane potential. Toxicol Appl Pharmacol 1997; 146:294-8. [PMID: 9344897 DOI: 10.1006/taap.1997.8244] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The purpose of this study was to investigate the mechanism of inorganic mercury (Hg) uptake in LLC-PK1 cells, a renal tubular epithelial cell line, and to compare the results with those reported previously by us in rat renal cortical epithelial (RCE) cells in primary culture. The LLC-PK1 cells were cultured for 3-12 days, incubated with 1 microM HgCl2 in Hanks' balanced salt solution at 4 or 37 degrees C for 30 min, and washed with phosphate-buffered saline containing BAL to remove the cell membrane-bound Hg. The uptake of Hg was higher in nonconfluent cultures than in confluent cultures and higher at 37 than at 4 degrees C. In confluent culture (Day 8) Hg uptake at 4 degrees C was only 27% of that at 37 degrees C. The initial accumulation of Hg (5 min) from different concentrations of HgCl2 (0.5-50 microM) was linear and did not show a tendency toward saturation, suggesting that a carrier-mediated process was not involved. Pretreatment of cells with 10 microM FCCP, a metabolic inhibitor and a proton ionophore, 0.5 mm DIDS, an anion transport inhibitor, or 0.5 mM ouabain, a Na+/K+-ATPase inhibitor, resulted in 72, 60, and 57% reduction in Hg uptake, respectively. Furthermore, replacement of 137 mm NaCl in the incubation medium with 137 mM KCl or LiCl or 274 mM mannitol caused 30, 45, and 87% reduction in Hg uptake, respectively. These results suggest that in LLC-PK1 cells, as in RCE cells, Hg uptake is inversely related to cell density and is influenced by membrane fluidity, membrane potential, and HCO3-/Cl- transporter.
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Affiliation(s)
- T Endo
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido 1757, Hokkaido, Ishikari-Tobetsu, 061-02, Japan
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Wu G. Prediction of uptake of methyl mercury by rat erythrocytes using a two-compartment model. Arch Toxicol 1995; 70:34-42. [PMID: 8750903 DOI: 10.1007/s002040050246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The uptake of methyl mercury (MeHg) by isolated rat erythrocytes was studied at 37 degrees C using MeHg-cysteine (MeHgCySH), MeHg-glutathione (MeHgGSH), MeHg-mercaptalbumin (MeHgMASH) and the mixture of MeHgCySH with MeHgGSH, MeHgCySH with MeHgMASH, MeHgGSH with MeHgMASH at different MeHg concentrations. The measured MeHg concentrations were analyzed according to the Akaike's information criterion in order to determine the suitable compartment model. After determining a two-compartment model, a model-independent two-compartment model was developed from the kinetics of uptake of MeHg at a concentration of 1 mmol MeHg/l packed erythrocytes using MeHgCySH, MeHgGSH and MeHgMASH, respectively. The developed two-compartment model was validated by predicting the kinetics of uptake of MeHg by rat erythrocytes at different MeHg concentrations and different mixtures of MeHg-complexes. Then, the predicted values were compared with the measured values. The results suggested: 1) MeHg uptake appeared suitable to be described by a two-compartment model, while using MeHgGSH, MeHgMASH, MeHgCySH at lower concentrations and the mixtures of MeHg-complexes; 2) MeHgCySH uptake was slowest among three kinds of MeHg-complexes, although a postulated cysteine-facilitated MeHgCySH transport system might exist in erythrocyte membrane; 3) the mixture of MeHg-complexes might facilitate MeHgCySH uptake; 4) there might be a second MeHg intracellular compartment in rat erythrocytes.
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Affiliation(s)
- G Wu
- Biochemical Section, National Institute for Minamata Disease, Kumamoto, Japan
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