title: Modulation of vasodilator response via the nitric oxide pathway after acute methyl mercury chloride exposure in rats.
abstract: Mercury exposure induces endothelial dysfunction leading to loss of endothelium-dependent vasorelaxation due to decreased nitric oxide (NO) bioavailability via increased oxidative stress. Our aim was to investigate whether acute treatment with methyl mercury chloride changes the endothelium-dependent vasodilator response and to explore the possible mechanisms behind the observed effects. Wistar rats were treated with methyl mercury chloride (5 mg/kg, po.). The methyl mercury chloride treatment resulted in an increased aortic vasorelaxant response to acetylcholine (ACh). In methyl-mercury-chloride-exposed rats, the % change in vasorelaxant response of ACh in presence of Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 10(-4) M) was significantly increased, and in presence of glybenclamide (10(-5) M), the response was similar to that of untreated rats, indicating the involvement of NO and not of endothelium-derived hyperpolarizing factor (EDHF). In addition, superoxide dismutase (SOD) + catalase treatment increased the NO modulation of vasodilator response in methyl-mercury-chloride-exposed rats. Our results demonstrate an increase in the vascular reactivity to ACh in aorta of rats acutely exposed to methyl mercury chloride. Methyl mercury chloride induces nitric oxide synthase (NOS) and increases the NO production along with inducing oxidative stress without affecting the EDHF pathway.
authors.affiliation: School of Sciences, Indira Gandhi National Open University, New Delhi 110068, India.
authors.forename: S
authors.initials: S
authors.lastname: Omanwar
authors.forename: B
authors.initials: B
authors.lastname: Saidullah
authors.forename: K
authors.initials: K
authors.lastname: Ravi
authors.forename: M
authors.initials: M
authors.lastname: Fahim
mesh_terms: D000109:Acetylcholine / Q000008:administration & dosage*; D000818:Animals; D001682:Biological Availability; D001685:Biological Factors / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D053858:Metabolic Networks and Pathways / Q000187:drug effects; D008767:Methylmercury Compounds / Q000008:administration & dosage*; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D009924:Organ Culture Techniques; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D001685:Biological Factors; D008767:Methylmercury Compounds; D014665:Vasodilator Agents; C067410:endothelium-dependent hyperpolarization factor; D009569:Nitric Oxide; D008315:Malondialdehyde; D019001:Nitric Oxide Synthase; D000109:Acetylcholine; C004925:methylmercuric chloride
references.citation: Braz J Med Biol Res. 2006 Mar;39(3):415-8
references.pmid: 16501822
references.citation: Nitric Oxide. 2012 Jun 30;27(1):59-66
references.pmid: 22561111
references.citation: Exp Eye Res. 2013 Apr;109:60-6
references.pmid: 23434456
references.citation: Braz J Med Biol Res. 1999 Aug;32(8):989-97
references.pmid: 10454761
references.citation: Acta Pharmacol Sin. 2010 Oct;31(10):1324-8
references.pmid: 20835265
references.citation: PLoS One. 2013;8(2):e55806
references.pmid: 23390552
references.citation: Arch Environ Contam Toxicol. 2000 Jul;39(1):124-30
references.pmid: 10790511
references.citation: Clin Chim Acta. 1983 Apr 25;129(3):319-22
references.pmid: 6851170
references.citation: Toxicol Appl Pharmacol. 1987 Jun 15;89(1):144-7
references.pmid: 3590186
references.citation: Br J Pharmacol. 2000 Aug;130(8):1983-91
references.pmid: 10952691
references.citation: J Gastroenterol Hepatol. 2007 Jun;22(6):870-6
references.pmid: 17565643
references.citation: Br J Pharmacol. 1999 Apr;126(8):1872-80
references.pmid: 10372832
references.citation: Med Pr. 2010;61(4):381-91
references.pmid: 20865852
references.citation: Altern Ther Health Med. 2007 Mar-Apr;13(2):S128-33
references.pmid: 17405690
references.citation: Br J Ind Med. 1989 Jun;46(6):370-5
references.pmid: 2818969
references.citation: Clin Exp Immunol. 2003 Dec;134(3):538-44
references.pmid: 14632763
references.citation: Hum Exp Toxicol. 2011 Nov;30(11):1777-84
references.pmid: 21148200
references.citation: Toxicol Ind Health. 2013 Mar;29(2):169-74
references.pmid: 22080037
references.citation: J Pharmacol Exp Ther. 1995 Mar;272(3):1011-5
references.pmid: 7534350
references.citation: J Intern Med. 2000 Jan;247(1):11-7
references.pmid: 10672126
references.citation: Comp Biochem Physiol C Toxicol Pharmacol. 2008 Mar;147(2):252-60
references.pmid: 18093879
references.citation: Arterioscler Thromb Vasc Biol. 1998 Aug;18(8):1312-21
references.pmid: 9714139
references.citation: Am J Physiol Renal Physiol. 2012 Apr 1;302(7):F840-52
references.pmid: 22205225
references.citation: J Pharmacol Exp Ther. 2009 Feb;328(2):610-20
references.pmid: 19008412
references.citation: Am J Physiol Heart Circ Physiol. 2008 Sep;295(3):H1033-H1043
references.pmid: 18599595
references.citation: Neurotoxicology. 2010 Jan;31(1):10-6
references.pmid: 19833149
references.citation: Sci Total Environ. 1990 Dec 1;99(1-2):23-35
references.pmid: 2270468
references.citation: Cardiovasc Res. 2007 Sep 1;75(4):710-8
references.pmid: 17659266
references.citation: N Engl J Med. 2011 Mar 24;364(12):1116-25
references.pmid: 21428767
references.citation: Nitric Oxide. 2008 Jun;18(4):287-95
references.pmid: 18307997
references.citation: WMJ. 2009 Aug;108(5):250-2
references.pmid: 19743756
references.citation: Br J Pharmacol. 2006 Jul;148(5):629-39
references.pmid: 16702995
references.citation: Altern Ther Health Med. 2005 Jul-Aug;11(4):18-25
references.pmid: 16053118
references.citation: Hypertension. 1998 Mar;31(3):872-7
references.pmid: 9495275
references.citation: Toxicology. 2003 Nov 5;192(2-3):179-88
references.pmid: 14580785