Effect of opioid blockade on insulin and growth hormone (GH) secretion in patients with polycystic ovary syndrome: the heterogeneity of impaired GH secretion is related to both obesity and hyperinsulinism
P. Villa et al., Effect of opioid blockade on insulin and growth hormone (GH) secretion in patients with polycystic ovary syndrome: the heterogeneity of impaired GH secretion is related to both obesity and hyperinsulinism, FERT STERIL, 71(1), 1999, pp. 115-121
Objective: To investigate the involvement of opioid tone, obesity, and hype
rinsulinemia in GH secretion in women with polycystic ovary syndrome (PCOS)
.
Design: Controlled clinical study.
Setting: Catholic University of Sacred Heart School of Medicine in Pome, It
aly.
Patient(s): Twenty-two patients with PCOS and 14 healthy, normally ovulatin
g volunteers, matched for age and body mass index.
Intervention(s): Patients underwent a GH-releasing hormone (GHRH) test and
an oral glucose tolerance test before and after 4-5 weeks of treatment with
50 mg/d of naltrexone.
Main Outcome Measure(s): Serum concentrations of GH, insulin, glucose, ster
oids, and gonadotropins, as well as the GH area under the curve (AUC-GH) an
d the insulin area under the curve (AUC-I), were measured before and after
naltrexone treatment.
Result(s): In patients with PCOS, the administration of naltrexone increase
d the GH response to the GHRH test without interfering with the insulin res
ponse to the oral glucose tolerance test. However, the GH response to the G
HRH test was improved significantly only in lean patients with PCOS, wherea
s obese patients with PCOS did not show any improvement in GH secretion. In
obese control subjects, the treatment reduced plasma basal insulin concent
rations and increased the AUC-GH, whereas in lean control subjects, the tre
atment reduced the GHRH-induced response. In normoinsulinemic patients with
PCOS, the GH response to the GHRH test increased significantly after treat
ment, whereas the AUG-I was not affected. In hyperinsulinemic patients with
PCOS, treatment with naltrexone significantly reduced the AUG-I, whereas t
he AUC-GH increased only in lean hyperinsulinemic patients with PCOS.
Conclusion(s): Naltrexone treatment improves GHRH-induced GH secretion in p
atients with PCOS. However, this GH response is heterogeneously represented
in relation to both obesity and hyperinsulinism. (C) 1998 by American Soci
ety for Reproductive Medicine.