Chronic low-level arsenite exposure through drinking water increases blood pressure and promotes concentric left ventricular hypertrophy in female mice

Toxicol Pathol. 2012 Apr;40(3):504-12. doi: 10.1177/0192623311432297. Epub 2012 Jan 3.

Abstract

Cardiovascular disease is the leading cause of death in the United States and worldwide. High incidence of cardiovascular diseases has been linked to populations with elevated arsenic content in their drinking water. Although this correlation has been established in many epidemiological studies, a lack of experimental models to study mechanisms of arsenic-related cardiovascular pathogenesis has limited our understanding of how arsenic exposure predisposes for development of hypertension and increased cardiovascular mortality. Our studies show that mice chronically exposed to drinking water containing 100 parts per billion (ppb) sodium arsenite for 22 weeks show an increase in both systolic and diastolic blood pressure. Echocardiographic analyses as well as histological assessment show concentric left ventricular hypertrophy, a primary cardiac manifestation of chronic hypertension. Live imaging by echocardiography shows a 43% increase in left ventricular mass in arsenic-treated animals. Relative wall thickness (RWT) was calculated showing that all the arsenic-exposed animals show an RWT greater than 0.45, indicating concentric hypertrophy. Importantly, left ventricular hypertrophy, although often associated with chronic hypertension, is an independent risk factor for cardiovascular-related mortalities. These results suggest that chronic low-level arsenite exposure promotes the development of hypertension and the comorbidity of concentric hypertrophy.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Analysis of Variance
  • Animals
  • Arsenites / administration & dosage
  • Arsenites / toxicity*
  • Blood Pressure / drug effects*
  • Drinking Water / standards
  • Echocardiography
  • Female
  • Histocytochemistry
  • Hypertension / chemically induced*
  • Hypertrophy, Left Ventricular / chemically induced*
  • Hypertrophy, Left Ventricular / pathology
  • Mice
  • Sodium Compounds / administration & dosage
  • Sodium Compounds / toxicity*
  • Toxicity Tests, Chronic

Substances

  • Arsenites
  • Drinking Water
  • Sodium Compounds
  • sodium arsenite