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Title: Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers

Abstract

Erythrocytes are the route of lead distribution to organs and tissues. The effect of lead on calcium homeostasis in human erythrocytes and other excitable cells is not known. In the present work we studied the effect of lead intoxication on the uptake and efflux (measured as (Ca{sup 2+}-Mg{sup 2+})-ATPase activity) of calcium were studied in erythrocytes obtained from lead-exposed workers. Blood samples were taken from 15 workers exposed to lead (blood lead concentration 74.4 {+-} 21.9 {mu}g/dl) and 15 non-exposed workers (9.9 {+-} 2 {mu}g/dl). In erythrocytes of lead-exposed workers, the intracellular free calcium was 79 {+-} 13 nM, a significantly higher concentration (ANOVA, P < 0.01) than the one detected in control (30 {+-} 9 nM). The enhanced intracellular free calcium was associated with a higher osmotic fragility and with important modifications in erythrocytes shape. The high intracellular free calcium in lead-exposed workers was also related to a 100% increase in calcium incorporation and to 50% reduction of (Ca{sup 2+}-Mg{sup 2+})-ATPase activity. Lipid peroxidation was 1.7-fold higher in erythrocytes of lead-exposed workers as compared with control. The alteration on calcium equilibrium in erythrocytes is discussed in light of the toxicological effects in lead-exposed workers.

Authors:
 [1];  [2];  [1];  [3];  [4];  [5]
  1. Department of Biochemistry, CINVESTAV-IPN, P.O. Box 14-740, Mexico City 07000 (Mexico)
  2. Department of Pharmacology, Faculty of Medicine, UNAM, Mexico City (Mexico)
  3. CIATEC, A.C. (Mexico)
  4. Medical Center Medic Unit 1 Bajio, IMSS, Leon Gto. (Mexico)
  5. Department of Biochemistry, CINVESTAV-IPN, P.O. Box 14-740, Mexico City 07000 (Mexico). E-mail: jcalder@cinvestav.mx
Publication Date:
OSTI Identifier:
20976892
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 220; Journal Issue: 1; Other Information: DOI: 10.1016/j.taap.2006.10.016; PII: S0041-008X(06)00378-4; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CALCIUM; CALCIUM IONS; DAMAGE; ERYTHROCYTES; HOMEOSTASIS; LEAD; LIPIDS; MAGNESIUM IONS; ORGANS; OXIDATION; PERSONNEL; UPTAKE

Citation Formats

Quintanar-Escorza, M.A., Gonzalez-Martinez, M.T., Navarro, L., Maldonado, M., Arevalo, B., and Calderon-Salinas, J.V.. Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers. United States: N. p., 2007. Web. doi:10.1016/j.taap.2006.10.016.
Quintanar-Escorza, M.A., Gonzalez-Martinez, M.T., Navarro, L., Maldonado, M., Arevalo, B., & Calderon-Salinas, J.V.. Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers. United States. doi:10.1016/j.taap.2006.10.016.
Quintanar-Escorza, M.A., Gonzalez-Martinez, M.T., Navarro, L., Maldonado, M., Arevalo, B., and Calderon-Salinas, J.V.. Sun . "Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers". United States. doi:10.1016/j.taap.2006.10.016.
@article{osti_20976892,
title = {Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers},
author = {Quintanar-Escorza, M.A. and Gonzalez-Martinez, M.T. and Navarro, L. and Maldonado, M. and Arevalo, B. and Calderon-Salinas, J.V.},
abstractNote = {Erythrocytes are the route of lead distribution to organs and tissues. The effect of lead on calcium homeostasis in human erythrocytes and other excitable cells is not known. In the present work we studied the effect of lead intoxication on the uptake and efflux (measured as (Ca{sup 2+}-Mg{sup 2+})-ATPase activity) of calcium were studied in erythrocytes obtained from lead-exposed workers. Blood samples were taken from 15 workers exposed to lead (blood lead concentration 74.4 {+-} 21.9 {mu}g/dl) and 15 non-exposed workers (9.9 {+-} 2 {mu}g/dl). In erythrocytes of lead-exposed workers, the intracellular free calcium was 79 {+-} 13 nM, a significantly higher concentration (ANOVA, P < 0.01) than the one detected in control (30 {+-} 9 nM). The enhanced intracellular free calcium was associated with a higher osmotic fragility and with important modifications in erythrocytes shape. The high intracellular free calcium in lead-exposed workers was also related to a 100% increase in calcium incorporation and to 50% reduction of (Ca{sup 2+}-Mg{sup 2+})-ATPase activity. Lipid peroxidation was 1.7-fold higher in erythrocytes of lead-exposed workers as compared with control. The alteration on calcium equilibrium in erythrocytes is discussed in light of the toxicological effects in lead-exposed workers.},
doi = {10.1016/j.taap.2006.10.016},
journal = {Toxicology and Applied Pharmacology},
number = 1,
volume = 220,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}
  • Blood lead concentration (Pb-B), aminolevulinic acid dehydratase (ALAD), and gamma-GT were measured in 265 workers industrially exposed to lead and in 184 patients with liver disease resulting from alcohol consumption. The first group was divided according to alcohol use, i.e., nondrinkers, moderate drinkers, and heavy drinkers. The second group was divided according to the following criteria: hepatopatic without cirrhosis, hepatopatic with compensated cirrhosis, and hepatopatic with decompensated cirrhosis. Heavy drinkers who were industrially exposed had the highest Pb-B (40.4 +/- 14.6 micrograms/dl) and the lowest ALAD (22.2 +/- 9.1 U/L). The correlations between Pb-B and ALAD show no significant changemore » with the increase of Pb-B. In the alcoholic group, 76 patients with alcoholic liver disease without cirrhosis had the highest Pb-B (40.3-9.1 micrograms/dl) and ALAD the lowest (18.6 +/- 7.7 U/L). The negative correlation between Pb-B and log ALAD disappeared completely in individuals with Pb-B that exceeded 50 micrograms/dl, independent from the seriousness of illness.« less
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