Impact of toxic agents or adverse conditions on thermoregulatory function in awake rodents

(1) In response to exposure to toxic xenobiotic agents, rodents demonstrate significant acute and subacute decreases in important indices of thermoreg ulatory and cardiovascular function. (2) This response has been observed in a number of studies in our laboratory and appears remarkably consistent, d espite the variety of agents and exposure routes tested. (3) Animals with c ardiopulmonary disease exhibit a potentiated response and may be at increas ed risk for adverse arrhythmic events and lethality. (4) Epidemiological st udies have shown a strong association between human exposure to particulate matter (PM) and increased morbidity and mortality, particularly in cardiop ulmonary-compromised individuals, (5) We have previously reported that vari ous surrogate PM induce a robust hypothermia in rats, along with significan t decreases in cardiac function, leading to arrhythmogenesis and lethality. (6) The present studies extend this research by assessing the contribution of the primary metallic constituents of PM towards the observed toxic effe cts. Published by Elsevier Science Ltd.