Growth hormone (GH) response to combined pyridostigmine and GH-releasing hormone administration in patients with Prader-Labhard-Willi syndrome.
We evaluated the GH response to combined administration of pyridostigmine (PD), a cholinergic agonist, and GH-releasing hormone (GHRH) (60 mg PD given orally 60 min before the GHRH bolus) as well as baseline IGF-I concentrations in 10 patients (5 males and 5 females, age 6.0-24 years) with Prader-Labhard-Willi (PLW) syndrome, 8 prepubertal obese children (4 males and 4 females, age 5.6-12.0 years) and 9 prepubertal short normal children (7 males and 2 females, age 8.0-12.8 years). Mean GH responses to PD+GHRH were significantly lower (p < 0.0001) in the PLW patients (13.8 +/- 3.3 micrograms/l) than in the short normal children (52.2 +/- 9.0 micrograms/l) and similar to those of the obese children (14.3 +/- 3.2 micrograms/l). Mean serum IGF-I levels were significantly lower (p < 0.05) in the PLW patients (117.5 +/- 26.4 micrograms/l) than in the obese (329.3 +/- 88.0 micrograms/l) and the short normal children (214.3 +/- 38.3 micrograms/l). Two of the PLW patients had absent GH responses to PD+GHRH associated with subnormal IGF-I concentrations, indicating pituitary GH deficiency. When these 2 cases were excluded from the statistical calculation, mean peak GH responses to PD+GHRH remained significantly lower (p < 0.0001) in the PLW patients (17.1 +/- 3.0 micrograms/l), while their mean serum IGF-I concentrations (143.4 +/- 71.5 micrograms/l) were not significantly different from those of the other two groups. These results indicate that patients with the PLW syndrome have a reduced or absent GH secretory reserve associated in some cases with low levels of IGF-I.(ABSTRACT TRUNCATED AT 250 WORDS)
Cappa
M
M
Divisione di Endocrinologia, Ospedale Bambino Gesù, Roma, Italia.
Grossi
A
A
Borrelli
P
P
Ghigo
E
E
Bellone
J
J
Benedetti
S
S
Carta
D
D
Loche
S
S
D000293:Adolescent; D000328:Adult; D002648:Child; D004359:Drug Therapy, Combination; D005260:Female; D006130:Growth Disorders / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology; D013006:Growth Hormone / Q000097:blood / Q000172:deficiency / Q000378:metabolism*; D013007:Growth Hormone-Releasing Hormone / Q000008:administration & dosage*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male; D009765:Obesity / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology; D011218:Prader-Willi Syndrome / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D011729:Pyridostigmine Bromide / Q000008:administration & dosage*
D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone; D011729:Pyridostigmine Bromide