Circadian variations in plasma ACTH, cortisol and beta-endorphin levels in normal-weight bulimic women.
In order to establish possible alterations in the secretory patterns of adrenocorticotropic hormone (ACTH), cortisol and/or beta-endorphin in bulimia nervosa, the circadian fluctuations of these hormones were evaluated in blood samples taken at 1-hour intervals over 24 h. Eleven bulimic women with normal body weight and 8 weight- and age-matched normal controls were tested during the follicular phase (days 6-8) of normal menstrual cycles. All women were hospitalized for bulimia or for checkup examinations and were tested 3 days after hospital admission. Both normal and bulimic women showed maximal ACTH, cortisol and beta-endorphin levels at 08.00 h, with minimal ACTH and beta-endorphin levels at midnight and cortisol levels at 02.00 h. The general temporal structure of all hormonal secretions coincided in the two groups. However, whereas all measured ACTH/cortisol levels were quantitatively similar in the two groups, plasma beta-endorphin concentrations were significantly higher in bulimic than in control subjects at all examined time points. The enhancement in the overall 24-hour beta-endorphin secretion suggests the presence of an increased opioid tonus in bulimic women, which might play a role in the pathophysiology of the eating disorder.
Vescovi
P P
PP
Chair of Medical Clinic, University of Parma, Italy.
Rastelli
G
G
Volpi
R
R
Chiodera
P
P
Di Gennaro
C
C
Coiro
V
V
D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000328:Adult; D002032:Bulimia / Q000097:blood* / Q000503:physiopathology; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D013997:Time Factors; D001615:beta-Endorphin / Q000097:blood*
D001615:beta-Endorphin; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone