Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide.
We investigated whether exposure to small concentrations of lead alters blood pressure and vascular reactivity. Male Wistar rats were sorted randomly into the following two groups: control (Ct) and treatment with 100 ppm of lead (Pb), which was added to drinking water, for 30 days. Systolic blood pr...
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2015-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC4373949?pdf=render |
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| author | Karolini Zuqui Nunes Dieli Oliveira Nunes Edna Aparecida Silveira Camila Almenara Cruz Pereira Gilson Brás Broseghini Filho Dalton Valentim Vassallo Mirian Fioresi |
| author_facet | Karolini Zuqui Nunes Dieli Oliveira Nunes Edna Aparecida Silveira Camila Almenara Cruz Pereira Gilson Brás Broseghini Filho Dalton Valentim Vassallo Mirian Fioresi |
| author_sort | Karolini Zuqui Nunes |
| collection | DOAJ |
| description | We investigated whether exposure to small concentrations of lead alters blood pressure and vascular reactivity. Male Wistar rats were sorted randomly into the following two groups: control (Ct) and treatment with 100 ppm of lead (Pb), which was added to drinking water, for 30 days. Systolic blood pressure (BP) was measured weekly. Following treatment, aortic ring vascular reactivity was assessed. Tissue samples were properly stored for further biochemical investigation. The lead concentration in the blood reached approximately 8 μg/dL. Treatment increased blood pressure and decreased the contractile responses of the aortic rings to phenylephrine (1 nM-100 mM). Following N-nitro-L arginine methyl ester (L-NAME) administration, contractile responses increased in both groups but did not differ significantly between them. Lead effects on Rmax were decreased compared to control subjects following superoxide dismutase (SOD) administration. Catalase, diethyldithiocarbamic acid (DETCA), and apocynin increased the vasoconstrictor response induced by phenylephrine in the aortas of lead-treated rats but did not increase the vasoconstrictor response in the aortas of untreated rats. Tetraethylammonium (TEA) potentiated the vasoconstrictor response induced by phenylephrine in aortic segments in both groups, but these effects were greater in lead-treated rats. The co-incubation of TEA and catalase abolished the vasodilatory effect noted in the lead group. The present study is the first to demonstrate that blood lead concentrations well below the values established by international legislation increased blood pressure and decreased phenylephrine-induced vascular reactivity. The latter effect was associated with oxidative stress, specifically oxidative stress induced via increases in hydrogen peroxide levels and the subsequent effects of hydrogen peroxide on potassium channels. |
| first_indexed | 2024-12-13T14:55:45Z |
| format | Article |
| id | doaj.art-039d3feefea6453a8a95f95a21155f1a |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-13T14:55:45Z |
| publishDate | 2015-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-039d3feefea6453a8a95f95a21155f1a2022-12-21T23:41:14ZengPublic Library of Science (PLoS)PLoS ONE1932-62032015-01-01103e012096510.1371/journal.pone.0120965Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide.Karolini Zuqui NunesDieli Oliveira NunesEdna Aparecida SilveiraCamila Almenara Cruz PereiraGilson Brás Broseghini FilhoDalton Valentim VassalloMirian FioresiWe investigated whether exposure to small concentrations of lead alters blood pressure and vascular reactivity. Male Wistar rats were sorted randomly into the following two groups: control (Ct) and treatment with 100 ppm of lead (Pb), which was added to drinking water, for 30 days. Systolic blood pressure (BP) was measured weekly. Following treatment, aortic ring vascular reactivity was assessed. Tissue samples were properly stored for further biochemical investigation. The lead concentration in the blood reached approximately 8 μg/dL. Treatment increased blood pressure and decreased the contractile responses of the aortic rings to phenylephrine (1 nM-100 mM). Following N-nitro-L arginine methyl ester (L-NAME) administration, contractile responses increased in both groups but did not differ significantly between them. Lead effects on Rmax were decreased compared to control subjects following superoxide dismutase (SOD) administration. Catalase, diethyldithiocarbamic acid (DETCA), and apocynin increased the vasoconstrictor response induced by phenylephrine in the aortas of lead-treated rats but did not increase the vasoconstrictor response in the aortas of untreated rats. Tetraethylammonium (TEA) potentiated the vasoconstrictor response induced by phenylephrine in aortic segments in both groups, but these effects were greater in lead-treated rats. The co-incubation of TEA and catalase abolished the vasodilatory effect noted in the lead group. The present study is the first to demonstrate that blood lead concentrations well below the values established by international legislation increased blood pressure and decreased phenylephrine-induced vascular reactivity. The latter effect was associated with oxidative stress, specifically oxidative stress induced via increases in hydrogen peroxide levels and the subsequent effects of hydrogen peroxide on potassium channels.http://europepmc.org/articles/PMC4373949?pdf=render |
| spellingShingle | Karolini Zuqui Nunes Dieli Oliveira Nunes Edna Aparecida Silveira Camila Almenara Cruz Pereira Gilson Brás Broseghini Filho Dalton Valentim Vassallo Mirian Fioresi Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide. PLoS ONE |
| title | Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide. |
| title_full | Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide. |
| title_fullStr | Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide. |
| title_full_unstemmed | Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide. |
| title_short | Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide. |
| title_sort | chronic lead exposure decreases the vascular reactivity of rat aortas the role of hydrogen peroxide |
| url | http://europepmc.org/articles/PMC4373949?pdf=render |
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