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Habibian A, Abyadeh M, Abyareh M, Rahimi Kakavandi N, Habibian A, Khakpash M, Ghazi-Khansari M. Association of maternal lead exposure with the risk of preterm: a meta-analysis. J Matern Fetal Neonatal Med 2021; 35:7222-7230. [PMID: 34210236 DOI: 10.1080/14767058.2021.1946780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND The relationship between maternal lead level and risk of preterm birth (PTB) remained controversial. Therefore, herein we performed this meta-analysis to investigate the association of maternal blood, urine and cord blood lead level with the risk of PTB using observational studies. METHODS A systematic search was conducted in PubMed, EMBASE and Ovid Medline databases from inception to August 2019, and sixteen studies with 65600 participants investigating the association between maternal lead level and PTB were included in our meta-analysis. Odds ratios (ORs) and 95% confidence intervals (95% CI) were calculated for the highest versus lowest lead level by random-effects model. RESULTS Overall, the pooled OR of all included articles for the highest versus lowest PTB score was 1.29 (95% CI = 1.14-1.46; I2 = 80.4%, p < .001), and the results revealed a direct and significant relationship between second and third trimester blood lead level (BLL) and PTB (OR 2nd trimester= 1.61, 95% CI = 1.08-2.40, OR 3rd trimester= 1.57, 95% CI = 1.11-2.23). CONCLUSION Results of this meta-analysis showed that maternal BLL is directly associated with the risk of PTB.
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Affiliation(s)
- Ahmad Habibian
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Morteza Abyadeh
- Department of Molecular Systems Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Mostafa Abyareh
- Department of Environment, Faculty of Natural Resources, Yazd University, Yazd, Iran
| | - Nader Rahimi Kakavandi
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Atefeh Habibian
- Department of Midwifery, School of Medicine, Islamic Azad University, Zahedan Branch, Zahedan, Iran
| | - Maliheh Khakpash
- Department of Nursing, School of Nursing and Midwifery, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Mahmoud Ghazi-Khansari
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Relation Between Lead Exposure and Trends in Blood Pressure in Children. Am J Cardiol 2018; 122:1890-1895. [PMID: 30292331 DOI: 10.1016/j.amjcard.2018.08.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 08/10/2018] [Accepted: 08/16/2018] [Indexed: 11/20/2022]
Abstract
Obesity raises blood pressure (BP) in children and adults. Nevertheless, as obesity increased around the globe, population systolic and diastolic blood pressures were flat or fell. Examining children is insightful because pediatric trends are largely unconfounded by antihypertensive therapy. Decomposing BP into arterial types, large artery measures (pulse pressure) increased in concert with obesity while small artery measures (mean arterial pressure, [MAP]) decreased, suggesting small arteries are the locus of the countervailing temporal trends. Pediatric lead exposure decreased as pediatric obesity rose. Over the period of rising obesity, we examined the association between lead exposure and temporal trends in BP. We analyzed anthropometric, BP, and laboratory data on 8-17 year old children from the serial cross-sectional National Health and Nutrition Examination Surveys 1976 through 2008. Multivariable adjusted survey regression was used to examine temporal trends in blood pressure in relation to blood lead concentrations (N = 13,501). As obesity prevalence rose from 5.3% to 24.5%, age-sex adjusted systolic BP was flat (-0.01 [95% confidence interval (CI) -0.06, 0.04] mm Hg/yr, p = 0.8), diastolic BP and MAP decreased (respectively -0.28 [-0.32, -0.24] and -0.19 [CI -0.23, -0.15], both p<0.0001) while pulse pressure increased (0.28 [0.23, 0.32], p<0.001). Accounting for blood lead concentration attenuated the decreasing MAP trend by 67%. In conclusion, the contrary trends in pediatric BP during the rise of pediatric obesity may be substantially attributable to decreasing lead exposure acting on small resistance arteries. These results have implications for globally observed BP trends in youth and adults. Environmental policy altering lead levels may have long-lasting cardiovascular benefits.
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Intermittent low-level lead exposure provokes anxiety, hypertension, autonomic dysfunction and neuroinflammation. Neurotoxicology 2018; 69:307-319. [PMID: 30098355 DOI: 10.1016/j.neuro.2018.08.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 07/31/2018] [Accepted: 08/04/2018] [Indexed: 01/14/2023]
Abstract
BACKGROUND Exposures to lead (Pb) during developmental phases can alter the normal course of development, with lifelong health consequences. Permanent Pb exposure leads to behavioral changes, cognitive impairment, sympathoexcitation, tachycardia, hypertension and autonomic dysfunction. However, the effects of an intermittent lead exposure are not yet studied. This pattern of exposure has been recently increasing due to migrations, implementation of school exchange programs and/or residential changes. OBJECTIVE To determine and compare lead effects on mammal's behavior and physiology, using a rat model of intermittent and permanent Pb exposures. METHODS Fetuses were intermittently (PbI) or permanently (PbP) exposed to water containing lead acetate (0.2% w/v) throughout life until adulthood (28 weeks of age). A control group (CTL) without any exposure to lead was also used. Anxiety was assessed by elevated plus maze (EPM) and locomotor activity and exploration by open field test (OFT). Blood pressure (BP), electrocardiogram (ECG), heart rate (HR), respiratory frequency (RF), sympathetic and parasympathetic activity and baro- and chemoreceptor reflex profiles were evaluated. Immunohistochemistry protocol for the assessment of neuroinflammation, neuronal loss (NeuN), gliosis and synaptic alterations (Iba-1, GFAP, Syn), were performed at the hippocampus. One-way ANOVA with Tukey's multiple comparison between means were used (significance p < 0.05) for statistical analysis. RESULTS The intermittent lead exposure produced a significant increase in diastolic and mean BP values, concomitant with a tendency to sympathetic overactivity (estimated by increased low-frequency power) and without significant changes in systolic BP, HR and RF. A chemoreceptor hypersensitivity and a baroreflex impairment were also observed, however, less pronounced when compared to the permanent exposure. Regarding behavioral changes, both lead exposure profiles showed an anxiety-like behavior without changes in locomotor and exploratory activity. Increase in GFAP and Iba-1 positive cells, without changes in NeuN positive cells were found in both exposed groups. Syn staining suffered a significant decrease in PbI group and a significant increase in PbP group. CONCLUSION This study is the first to show that developmental Pb exposure since fetal period can cause lasting impairments in physiological parameters. The intermittent lead exposure causes adverse health effects, i.e, hypertension, increased respiratory frequency and chemoreflex sensitivity, baroreflex impairment, anxiety, decreased synaptic activity, neuroinflammation and reactive gliosis, in some ways similar to a permanent exposure, however some are lower-grade, due to the shorter duration of exposure. This study brings new insights on the environmental factors that influence autonomic and cardiovascular systems during development, which can help in creating public policy strategies to prevent and control the adverse effects of Pb toxicity.
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Nakade UP, Sharma A, Choudhury S, Yadav RS, Garg SK. Lead Modulates Calcium Entry and Beta-Adrenoceptors Signaling to Produce Myometrial Relaxation in Rats. Biol Trace Elem Res 2017; 176:176-180. [PMID: 27502953 DOI: 10.1007/s12011-016-0813-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/27/2016] [Indexed: 01/04/2023]
Abstract
Modulation of myometrial spontaneity by lead acetate trihydrate (Pb) and its regulatory pathways were studied in estrogenized rats. Isometric tension in myometrial strips under a resting tension of 1 g was measured using data acquisition system-based physiograph and Lab Chart Pro v7.3.7 software. Lead produced a dose-dependent inhibitory effect on rat myometrium with a major effect on phasic contractions compared to tonic contractions along with a reduction in both amplitude and frequency of contraction. Lead (3 μM) significantly (p < 0.05) reduced CaCl2, and 80 mM KDS induced contractile response while potentiated the relaxant effect of phenylephrine. Based on our findings, it may be inferred that lead blocks calcium entry through VDCC and/or stimulates β-adrenoceptors adenylyl cyclase-C-AMP pathway to produce inhibitory effect on rat myometrium.
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Affiliation(s)
- Udayraj P Nakade
- Experimental Pharmacology Laboratory, Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan, (DUVASU), Mathura, 281001, India
| | - Abhishek Sharma
- Experimental Pharmacology Laboratory, Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan, (DUVASU), Mathura, 281001, India
| | - Soumen Choudhury
- Experimental Pharmacology Laboratory, Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan, (DUVASU), Mathura, 281001, India
| | - Rajkumar Singh Yadav
- Experimental Pharmacology Laboratory, Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan, (DUVASU), Mathura, 281001, India
| | - Satish Kumar Garg
- Experimental Pharmacology Laboratory, Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan, (DUVASU), Mathura, 281001, India.
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Zeng X, Xu X, Boezen HM, Huo X. Children with health impairments by heavy metals in an e-waste recycling area. CHEMOSPHERE 2016; 148:408-15. [PMID: 26829309 DOI: 10.1016/j.chemosphere.2015.10.078] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 10/10/2015] [Accepted: 10/19/2015] [Indexed: 02/05/2023]
Abstract
E-waste recycling has become a global environmental health issue. Pernicious chemicals escape into the environment due to informal and nonstandard e-waste recycling activities involving manual dismantling, open burning to recover heavy metals and open dumping of residual fractions. Heavy metals derived from electronic waste (e-waste), such as, lead (Pb), cadmium (Cd), chromium (Cr), manganese (Mn), nickel (Ni), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), aluminum (Al) and cobalt (Co), differ in their chemical composition, reaction properties, distribution, metabolism, excretion and biological transmission. Our previous studies showed that heavy metal exposure have adverse effects on children's health including lower birth weight, lower anogenital distance, lower Apgar scores, lower current weight, lower lung function, lower hepatitis B surface antibody levels, higher prevalence of attention-deficit/hyperactivity disorder, and higher DNA and chromosome damage. Heavy metals influence a number of diverse systems and organs, resulting in both acute and chronic effects on children's health, ranging from minor upper respiratory irritation to chronic respiratory, cardiovascular, nervous, urinary and reproductive disease, as well as aggravation of pre-existing symptoms and disease. These effects of heavy metals on children's health are briefly discussed.
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Affiliation(s)
- Xiang Zeng
- Laboratory of Environmental Medicine and Developmental Toxicology, and Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou University, 22 Xinling Road, Shantou 515041, China; Department of Epidemiology, University Medical Center Groningen, University of Groningen, 1 Hanzeplein, Groningen 9700RB, The Netherlands; Groningen Research Institute for Asthma and COPD (GRIAC), University Medical Center Groningen, University of Groningen, 1 Hanzeplein, Groningen 9700RB, The Netherlands
| | - Xijin Xu
- Laboratory of Environmental Medicine and Developmental Toxicology, and Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou University, 22 Xinling Road, Shantou 515041, China; Department of Cell Biology and Genetics, Shantou University Medical College, Shantou University, 22 Xinling Road, Shantou 515041, China
| | - H Marike Boezen
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, 1 Hanzeplein, Groningen 9700RB, The Netherlands; Groningen Research Institute for Asthma and COPD (GRIAC), University Medical Center Groningen, University of Groningen, 1 Hanzeplein, Groningen 9700RB, The Netherlands
| | - Xia Huo
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China.
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Hore SK, Choudhury S, Ahmad AH, Garg SK. Withania somnifera ameliorates lead-induced augmentation of adrenergic response in rat portal vein. Indian J Pharmacol 2014; 45:563-8. [PMID: 24347762 PMCID: PMC3847244 DOI: 10.4103/0253-7613.121365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 02/03/2013] [Accepted: 09/15/2013] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES Present study was undertaken to elucidate the ameliorating potential of Withania somnifera root extract (WRE) against lead-induced augmentation of adrenergic response in rat portal vein. MATERIALS AND METHODS In-vitro studies were conducted on effect of lead alone and lead+WRE on rat-isolated portal vein while in-vivo studies were done in three groups of 12 rats each; Group-II and III received 0.5% lead acetate and 1.0% WRE + 0.5% lead acetate, respectively, in drinking water for 12 weeks whereas group-I served as control. Adrenaline and noradrenaline levels in brain and blood were determined by HPLC assay while vascular reactivity of portal vein to lead and WRE was determined by measuring the isometric tension. RESULTS Following in-vitro exposure, lead did not alter the contractile effect of phenylephrine. In-vivo studies revealed that contractile effect of lead on portal vein was significantly potentiated and it was antagonized by prazosin (10(-7) M) and WRE (1%). WRE treatment significantly reduced elevated blood noradrenaline (37.80%) and restored noradrenaline level in brain (39.39%) in lead-exposed animals. These values were almost comparable to the control group. But it failed to significantly affect the blood and brain adrenaline levels. CONCLUSIONS Results suggest that following pre-exposure of rats to WRE, lead-induced augmentation of alpha 1-adrenoceptors mediated response was reversed possibly by regulating catecholamine release from nerve endings. Thus, WRE may be useful in therapeutic management of lead-induced hypertension.
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Affiliation(s)
- Subrata Kumar Hore
- Department of Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Viswavidyalaya Evam Go-Anusandhan Sansthan, Mathura, Uttar Pradesh, India
| | - Soumen Choudhury
- Department of Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Viswavidyalaya Evam Go-Anusandhan Sansthan, Mathura, Uttar Pradesh, India
| | - Abul Hasan Ahmad
- Department of Pharmacology and Toxicology, College of Veterinary and Animal Sciences, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India
| | - Satish Kumar Garg
- Department of Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Viswavidyalaya Evam Go-Anusandhan Sansthan, Mathura, Uttar Pradesh, India
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Fioresi M, Simões MR, Furieri LB, Broseghini-Filho GB, Vescovi MVA, Stefanon I, Vassallo DV. Chronic lead exposure increases blood pressure and myocardial contractility in rats. PLoS One 2014; 9:e96900. [PMID: 24841481 PMCID: PMC4026242 DOI: 10.1371/journal.pone.0096900] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 04/13/2014] [Indexed: 11/18/2022] Open
Abstract
We investigated the cardiovascular effects of lead exposure, emphasising its direct action on myocardial contractility. Male Wistar rats were sorted randomly into two groups: control (Ct) and treatment with 100 ppm of lead (Pb) in the drinking water. Blood pressure (BP) was measured weekly. At the end of the treatment period, the animals were anaesthetised and haemodynamic parameters and contractility of the left ventricular papillary muscles were recorded. Blood and tissue samples were properly stored for further biochemical investigations. Statistical analyses were considered to be significant at p<0.05. The lead concentrations in the blood reached approximately 13 µg/dL, while the bone was the site of the highest deposition of this metal. BP in the Pb-treated group was higher from the first week of lead exposure and remained at the same level over the next four weeks. Haemodynamic evaluations revealed increases in systolic (Ct: 96±3.79 vs. Pb: 116±1.37 mmHg) and diastolic blood pressure (Ct: 60±2.93 vs. Pb: 70±3.38 mmHg), left ventricular systolic pressure (Ct: 104±5.85 vs. Pb: 120±2.51 mmHg) and heart rate (Ct: 307±10 vs. Pb: 348±16 bpm). Lead treatment did not alter the force and time derivatives of the force of left ventricular papillary muscles that were contracting isometrically. However, our results are suggestive of changes in the kinetics of calcium (Ca++) in cardiomyocytes increased transarcolemmal Ca++ influx, low Ca++ uptake by the sarcoplasmic reticulum and high extrusion by the sarcolemma. Altogether, these results show that despite the increased Ca++ influx that was induced by lead exposure, the myocytes had regulatory mechanisms that prevented increases in force, as evidenced in vivo by the increased systolic ventricular pressure.
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Affiliation(s)
- Mirian Fioresi
- Department of Physiological Sciences, Federal University of Espírito Santo, Vitoria, Espírito Santo, Brazil
- Department of Nursing, Federal University of Espírito Santo, Vitoria, Espírito Santo, Brazil
- * E-mail:
| | - Maylla Ronacher Simões
- Department of Physiological Sciences, Federal University of Espírito Santo, Vitoria, Espírito Santo, Brazil
| | - Lorena Barros Furieri
- Department of Physiological Sciences, Federal University of Espírito Santo, Vitoria, Espírito Santo, Brazil
- Department of Nursing, Federal University of Espírito Santo, Vitoria, Espírito Santo, Brazil
| | | | | | - Ivanita Stefanon
- Department of Physiological Sciences, Federal University of Espírito Santo, Vitoria, Espírito Santo, Brazil
| | - Dalton Valentim Vassallo
- Department of Physiological Sciences, Federal University of Espírito Santo, Vitoria, Espírito Santo, Brazil
- Health Science Centre of Vitória-EMESCAM, Vitória, Espírito Santo, Brazil
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Abstract
Lead is a ubiquitous environmental toxin that is capable of causing numerous acute and chronic illnesses. Population studies have demonstrated a link between lead exposure and subsequent development of hypertension (HTN) and cardiovascular disease. In vivo and in vitro studies have shown that chronic lead exposure causes HTN and cardiovascular disease by promoting oxidative stress, limiting nitric oxide availability, impairing nitric oxide signaling, augmenting adrenergic activity, increasing endothelin production, altering the renin-angiotensin system, raising vasoconstrictor prostaglandins, lowering vasodilator prostaglandins, promoting inflammation, disturbing vascular smooth muscle Ca(2+) signaling, diminishing endothelium-dependent vasorelaxation, and modifying the vascular response to vasoactive agonists. Moreover, lead has been shown to cause endothelial injury, impede endothelial repair, inhibit angiogenesis, reduce endothelial cell growth, suppress proteoglycan production, stimulate vascular smooth muscle cell proliferation and phenotypic transformation, reduce tissue plasminogen activator, and raise plasminogen activator inhibitor-1 production. Via these and other actions, lead exposure causes HTN and promotes arteriosclerosis, atherosclerosis, thrombosis, and cardiovascular disease. In conclusion, studies performed in experimental animals, isolated tissues, and cultured cells have provided compelling evidence that chronic exposure to low levels of lead can cause HTN, endothelial injury/dysfunction, arteriosclerosis, and cardiovascular disease. More importantly, these studies have elucidated the cellular and molecular mechanisms of lead's action on cardiovascular/renal systems, a task that is impossible to accomplish using clinical and epidemiological investigations alone.
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Affiliation(s)
- Nosratola D Vaziri
- Division of Nephrology and Hypertension, UCI Medical Center, 101 The City Dr., Bldg. 53, Rm. 125, Rt. 81, Orange, CA 92868, USA.
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Heydari A, Norouzzadeh A, Khoshbaten A, Asgari A, Ghasemi A, Najafi S, Badalzadeh R. Effects of short-term and subchronic lead poisoning on nitric oxide methabolites and vascular responsiveness in rat. Toxicol Lett 2006; 166:88-94. [PMID: 16860498 DOI: 10.1016/j.toxlet.2006.05.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 05/26/2006] [Accepted: 05/29/2006] [Indexed: 10/24/2022]
Abstract
Chronic exposure to low levels of lead results in sustained hypertension in humans and experimental animals. The mechanism of lead-induced hypertension remains unclear. We investigated the short-term (4 and 8 weeks) and subchronic (12 weeks) effects of lead treatment on responsiveness of vascular adrenergic system and level of nitric oxide metabolites, that is, total nitrates and nitrites (NOx). Male Sprague-Dawley rats were treated with lead acetate (100 ppm in drinking water) for 12 weeks. Short-term lead administration resulted in marked elevation of blood pressure accompanied by significant reduction in serum NOx levels. In contrast, after subchronic lead administration the trend of decrease in NOx levels somehow reversed despite further increase in blood pressure. Both short-term and subchronic lead administration resulted in significant differences in vascular reactivity with respect to either vasoconstrictor (phenylephrine and clonidine) or vasodilator (isoproterenol) agents. We conclude that vascular adrenergic system and nitric oxide pathway change in short-term and subchronic phases of lead poisoning.
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Affiliation(s)
- Azhdar Heydari
- Department of Physiology and Biophysics, Baghyatollah University of Medical Sciences, Tehran, Iran.
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