5-HT2 RECEPTOR ANTAGONISM AND SLOW-WAVE SLEEP IN MAJOR DEPRESSION

Specific sleep disturbances such as reduced slow-wave sleep (SWS) and decreased serotonergic (5-HT) activity have been observed in depressive disorders. Ritanserin, a specific 5-HT2 receptor antagonist, has been shown to increase SWS in healthy subjects. This study explored the effects of a single dose or ritanserin (5 mg) on sleep electroencephalography in 18 major depressed patients and in 10 control subjects. Ritanserin affected SWS differently in the two groups. Although stage 3 increased significantly in the groups, in contrast to controls, there was no significant effect of ritanserin on stage 4 in depressed patients. In the depressed group, irritability and DSM-III-R melancholic type predicted 40" or the variance of stage 4 increment after ritanserin, as assessed by stepwise multiple regression. These results are in agreement with a potential 5-HT disturbance, particularly at the 5-HT2 receptor level, in some clinical forms of depression.