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Exposure to Low Lead Concentration for 7 Days Increases Blood Pressure and Reduces NO Effects in Resistance Arteries
Author(s) -
Vassallo Dalton Valentim,
Simões Maylla R,
Furieri Lorena B,
Broseghini Gilson B,
Vescovi Marcos VA,
Fiorim Jonaina,
Azevedo Bruna F,
Salaices Mercedes,
Padilha Alessandra Simões,
Stefa Ivanita,
Fioresi Mirian
Publication year - 2012
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.26.1_supplement.853.15
Subject(s) - myograph , blood pressure , phenylephrine , mesenteric arteries , medicine , endocrinology , lead acetate , enalapril , chemistry , vascular resistance , vasoconstriction , blood vessel , vasodilation , artery , angiotensin converting enzyme , toxicity
We investigated the effects of exposure to lead low concentration for 7 days on blood pressure and mesenteric arteries reactivity, and the role of NO and of the renin‐angiotensin system in the vasoconstrictor response to phenylephrine (PHE). Male Wistar rats (250–300 g) received lead acetate (100 ppm) during 7 days as drinking water or only water. Systolic (SBP), Diastolic blood Pressure (DBP) Heart Rate (HR) were measured. Blood lead concentration and ACE activity were measured. Mesenteric arteries (3rd branch) were mounted in a chamber myograph for measurement of isometric tension and concentration‐response curves to PHE were performed. Lead blood levels attained 5 ± 0.96 μg/dL, below blood lead reference value (60 μg/dL). SBP and DBP increased. The maximum contractile response to PHE did not differ in both groups. Incubation with L‐NAME increased the response to PHE in control but not in lead treated rats suggesting the reduction of endothelial modulation by NO. Enalapril effects and ACE activity did not differ in both groups. Results suggest that low concentration lead exposure after 7 days although increasing blood pressure does not change vascular reactivity but reduced the role of NO in resistance arteries. These results offer further evidence that short time lead exposure at small concentration is hazardous and a risk factor for cardiovascular disease. (CAPES, FAPES/CNPq).