Effects of intravenous corticotropin-releasing hormone upon sleep EEG in young healthy women

In young healthy male subjects the intravenously administered neuropeptide corticotropin-releasing hormone (CRH) decreased slow wave sleep (SWS) and rapid eye movement (REM) sleep. A sexual dimorphism was shown in sleep endocrine studies with the neuropeptides growth hormone releasing hormone (GHRH) and ghrelin. GHRH enhanced SWS in young males, whereas in young women SWS was reduced. In contrast to male subjects ghrelin had no sleep promoting effect in female subjects. We aimed to clarify whether a gender dimorphism exists in the effects of CRH on sleep EEG. In the present single-blind study we examined the effect of pulsatile administration of 4×50µg CRH (intravenous injection at 22:00, 23:00, 00:00 and 01:00) or placebo on sleep EEG. Eight young healthy women were included according to a randomised schedule. Each subject underwent two sessions and to minimize the influence of gonadal hormone activity the sleep EEG recordings took place during the follicular phase. In accordance to the findings in young men CRH induced a decrease of stage 3 (S3) sleep (CRH: S3 sleep mean=33.63min SEM 6.01min; placebo: S3 sleep mean 44.94min SEM 3.73min), but in contrast wakefulness increased in the second half of the night, whereas REM sleep was not affected by CRH. Sleep period time and sleep efficacy index were decreased by trend. The study demonstrated that systemic CRH administration impairs sleep in women.