Persistence of human growth hormone circadian rhythm in patients with homozygous beta-thalassemia.
Plasma levels of human growth hormone (hGH) were measured for an entire day every two hours, starting from midnight, in 6 healthy male subjects and in 6 male patients with homozygous beta-thalassemia, without evidence of any endocrine disease. The data were analyzed by the "cosinor" method, and the results show the presence of a significant (p < 0.05) circadian rhythm for hGH in both groups. Whereas no differences were found in mesors and acrophases between the two studied groups (p > 0.05), a statistically-significant (p < 0.05) difference was observed regarding amplitudes, being higher in the controls. These data suggest that in patients with beta-thalassemia major without evidence of any endocrine abnormality, the circadian secretory pattern of hGH is preserved, even if the rhythm amplitude is reduced: this could be a compensatory mechanism in order to stimulate growth.
Pasqualetti
P
P
Department of Internal Medicine, School of Medicine and Surgery, University of L'Aquila, Italy.
Collacciani
A
A
Natali
G F
GF
Colantonio
D
D
Casale
R
R
D000293:Adolescent; D000328:Adult; D002940:Circadian Rhythm; D013006:Growth Hormone / Q000096:biosynthesis*; D006801:Humans; D008297:Male; D017086:beta-Thalassemia / Q000378:metabolism*
D013006:Growth Hormone