IPSAPIRONE, A 5-HT1A AGONIST, SUPPRESSES REM-SLEEP EQUALLY IN UNMEDICATED DEPRESSED-PATIENTS AND NORMAL CONTROLS

To determine whether ipsapirone, a 5-HT1A agonist, differentially supp resses REM sleep in depressed patients compared with normal controls, we administered placebo, ipsapirone 10 mg, or ipsapirone 20 mg in a do uble-blind, random order before bedtime in 18 unmedicated patients wit h depression and 16 age-matched, gender-matched normal controls. Compa red to placebo, ipsapiuone affected REM sleep measures equally in depr essed patients and controls as follows: (1) increased XEM latency; (2) reduced total REM percent, XEM time, and XEM density; and (3) delayed the onset of REM sleep. In addition, ipsapirone had similar effects i n patients and controls in other sleep measures: (I) reduced total sle ep time; (2) delayed sleep onset time; and (3) increased sleep latency stage 1%, stage 2%, the amount of stage 3 & 4 sleep in the first non- REM period, and wake time after sleep onset. The study does not suppor t the hypothesis that downregulated 5-HT1A receptors mediate the patho physiology or sleep disturbances of depression, although further studi es are needed as these patients did not differ from controls in baseli ne sleep measures.