Effects of chronic cigarette smoking on behavior, EEG power spectrum, EEG activation ratio and visual evoked potential of freely moving rats

ABSTRACT

The present study was carried out to determine the effects of chronic tobacco smoking on behaviour, EEG power spectrum, EEG activation ratio and visual evoked potential [VEP] of freely moving rats. Simultaneous EEG records from the 4 electrodes were carried out one week later [as recovery and raining period] by means of differential recording of 12 channel EEG machine [Braintronix]. Sixty seconds EEG free of artifact were recorded after a tobacco smoking period of 15 min [0.01 mg/200 g] via inhalation route. FFT analysis was carried out for each actual trace to obtain power spectrum density for the recorded 60s period. Chronic Tobacco smoking over a period of 30 days of continuously daily single dose [0.01 mg/200 of rat per day] resulted in arousal increments as some behavioural activation [slight locomotor activation, periods of sniffing]. Also, there was less stimulant effects in the right than left hemisphere. Chronic Tobacco smoking over a period of 30 days of continuously daily single dose [0.01 mg/200 g or rat per day] resulted in Arousal increments as some behavioural activation [slight locomotor activation, periods of sniffing]. Also, there was less stimulant effects in the right than left hemisphere. Chronic Tobacco smoking resulted in decreases in percentage of relative power of delta-1, delta-2, theta-1, theta-2 and alpha-1 and increased percentage of relative power of alpha-2, beta-1 and beta-2 of brain waves. Hemispheric asymmetries were also assessed. When VEP analysis was done there were no differences between tobacco exposed and the unexposed condition. Also, there was a frequency shift of about 0.75 Hz in the alpha-1 frequency toward the higher frequency