SLEEP-DEPRIVATION IS A LESS POTENT AGENT THAN CLOMIPRAMINE IN INCREASING FIRING RATE IN LATERAL SEPTAL NEURONS IN THE RAT

Acute injection of clomipramine or a 24-hour period of sleep deprivati on produces an increased firing rate in lateral septal neurons of the rat. However, it is unknown whether changes in firing rate in lateral septal neurons also appear after repetitive treatments. This study exp lored and compared the effects of long-term clomipramine with those of sleep deprivation from 1 to 4 days in the firing rate of lateral sept al neurons. The firing rate increased after both treatments; however, maximal effects occurred on different days. Clomipramine (1.25 mg/kg, i.p., twice a day) produced a stable, increased firing rate after 20 d ays of treatment. Twenty-four hours of total sleep deprivation produce d changes in firing rate comparable to 10 days of clomipramine treatme nt. Changes in firing rate did not appear when animals were exposed to 12 h of sleep deprivation alternated with 12 h in housing cages. Ther efore, it is concluded that 24 h of total sleep deprivation is a less effective treatment than clomipramine for producing changes in firing rate in lateral septal neurons.