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Antidepressants and REM sleep in Wistar–Kyoto and Sprague–Dawley rats

2005; Elsevier BV; Volume: 522; Issue: 1-3 Linguagem: Inglês

10.1016/j.ejphar.2005.08.050

1879-0712

Magnus Ivarsson, Louise M. Paterson, Peter H. Hutson,

Olfactory and Sensory Function Studies

Compared to other rat strains, the Wistar–Kyoto rats show increased amount of REM sleep, one of the characteristic sleep changes observed in depressed patients. The aims of this study were firstly to validate a simple sleep stage discriminator and then compare the effect of antidepressants on suppression of rapid eye movement (REM) sleep in Wistar–Kyoto rats and an outbred rat strain (Sprague–Dawley). Rats were implanted with telemetry transmitters with electroencephalogram/electromyogram electrodes. Following recovery, the animals were orally dosed at light onset with either desipramine (20 mg/kg), fluoxetine (10 mg/kg), citalopram (10 or 40 mg/kg) or vehicle in a cross-over design. Every 12-s epoch was automatically scored as WAKE, NREM or REM sleep. Results confirm that Wistar–Kyoto rats show increased amount of REM sleep and decreased REM latency compared with Sprague–Dawley rats. All antidepressants significantly suppressed REM sleep in Sprague–Dawley rats, but only the high dose of citalopram suppressed REM sleep in Wistar–Kyoto rats. These findings suggest that the enhanced REM activity in Wistar–Kyoto rats is less sensitive to the effect of antidepressants and therefore does not provide any additional predictive validity for assessing antidepressant efficacy.