Ozone-induced bradycardia and arrhythmia and their relation to sleep-wakefulness in rats.
Rats were chronically implanted with electrodes for EEG, EMG and ECG recordings and exposed to 0.1 ppm, 0.2 ppm ozone (O3) or clean air as control for 5 consecutive days. Amounts of wakefulness (W), slow-wave sleep (SWS) and paradoxical sleep (PS) of the O3-exposed rats were not statistically different from respective control values. Compared with control rats, heart rates of the O3-exposed rats decreased and the number of bradyarrhythmic episodes increased with an increase in O3 levels. The O3-induced bradyarrhythmias occurred more prevalently in the order of W, SWS and PS state. Parasympathetic mechanisms were suggested on those cardiac abnormalities.
Arito
H
H
National Institute of Industrial Health, Kawasaki, Japan.
Uchiyama
I
I
Arakawa
H
H
Yokoyama
E
E
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced*; D001919:Bradycardia / Q000139:chemically induced*; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography; D004569:Electroencephalography; D004576:Electromyography; D008297:Male; D010126:Ozone / Q000633:toxicity*; D051381:Rats; D011919:Rats, Inbred Strains; D012890:Sleep / Q000187:drug effects*; D014851:Wakefulness / Q000187:drug effects*
D010126:Ozone