Basic Research in Cardiology

, Volume 102, Issue 6, pp 467–475

Direct and acute cardiotoxicity of ultrafine particles in young adult and old rat hearts

Authors

    • The Heart InstituteGood Samaritan Hospital
    • Division of Cardiovascular Medicine, Keck School of MedicineUniversity of Southern California
  • Paul Marjoram
    • Dept. of Preventive Medicine, Keck School of MedicineUniversity of Southern California
  • Michael T. Kleinman
    • Dept. of Community and Environmental MedicineUniversity of California Irvine
  • Robert A. Kloner
    • The Heart InstituteGood Samaritan Hospital
    • Division of Cardiovascular Medicine, Keck School of MedicineUniversity of Southern California
ORIGINAL CONTRIBUTION

DOI: 10.1007/s00395-007-0681-0

Cite this article as:
Simkhovich, B.Z., Marjoram, P., Kleinman, M.T. et al. Basic Res Cardiol (2007) 102: 467. doi:10.1007/s00395-007-0681-0

Abstract

Background

Air pollution is associated with significant increases in cardiac morbidity and mortality in the general population. The elderly cohort within the general population is considered at high risk for cardiac diseases. However the degree to which air pollutants affect cardiac responses in old hearts vs. their young adult counterparts has not been systematically addressed.

Objectives

We sought to investigate the response of young adult vs. old rat hearts to the direct exposure of ultrafine particles (UFP); i.e. when the UFP are directly instilled into the cardiac vasculature, and their effects are not dependent upon UFP inhalation.

Methods

The study was performed in isolated Langendorff-perfused rat hearts obtained from young adult (4 months old) and aged (26 months old) Fisher 344/Brown Norway rats. Two treatment groups (control and UFP-treated) were studied, and two ages (young adult and old) were studied within each group. Control hearts were perfused with buffer only, UFP-treated hearts were perfused with buffer containing ultrafine particles isolated from industrial diesel reference particulate matter. Systolic and end-diastolic pressures, positive and negative dP/dt, and coronary flow were measured.

Results

Young adult and old hearts demonstrated equal functional deterioration in response to direct infusion of UFP. Developed pressure in young adult UFP-treated hearts fell from 101±4 to 68±8 mmHg (a decrease by 33%, p<0.05). In the old UFP-treated hearts developed pressure fell by 35% (from 101±7 to 67±9mmHg, p<0.05). Positive dP/dt was equally affected in the young adult and old UFP-treated hearts and was decreased by 28% in both groups.

Conclusion

Ultrafine particles when instilled directly into the cardiac vasculature were equally cardiotoxic in young adult and old rat hearts.

Key words

air pollutionultrafine particlescardiotoxicity

Abbreviations

IDRM

industrial diesel reference particulate matter

NIST

National Institute of Standards and Technology

UFP

ultrafine particles

YC

young adult control hearts

OC

old control hearts

YUFP

young adult hearts treated with ultrafine particles

OUFP

old hearts treated with ultrafine particles

ROS

reactive oxygen species

NO

nitric oxide

Copyright information

© Steinkopff-Verlag 2007