Growth hormone secretion in Prader-Willi syndrome.
Integrated 12-hour growth hormone secretion studies, peak growth hormone response to clonidine provocation. Somatomedin-C levels, T-4 and TSH levels were studied in six growth-retarded children with the Prader-Willi syndrome, of whom five had a 15 q-karyotype. Only one of the subjects was obese. All showed abnormally low growth hormone secretion. None achieved a nocturnal peak above 10 micrograms/l, none had a mean nocturnal level over 1.8, and none showed a level above 8 micrograms/l after clonidine provocation. These findings contrasted with normal TSH in all and normal T-4 in five. These findings suggest that the poor linear growth in the Prader-Willi syndrome is caused by a true deficiency of growth hormone secretion, and that the low growth hormone levels observed in such cases are not an artifact of obesity.
Costeff
H
H
Child Development and Mental Retardation Center, University of Washington, Seattle.
Holm
V A
VA
Ruvalcaba
R
R
Shaver
J
J
D002648:Child; D005260:Female; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D011218:Prader-Willi Syndrome / Q000503:physiopathology*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood
D007334:Insulin-Like Growth Factor I; D013972:Thyrotropin; D013006:Growth Hormone; D013974:Thyroxine