Effect of the opioid blockade on the feeding-induced growth hormone response to growth hormone-releasing hormone in women with polycystic ovary syndrome.
OBJECTIVE
To investigate the effect of naloxone, an opioid receptor antagonist, on the release of growth hormone (GH) induced by the growth hormone-releasing hormone (GHRH) in normal-weight and obese women with PCOS in relation to feeding.


METHODS
Prospective clinical study.


METHODS
Academic research center.


METHODS
Seventeen women with PCOS (10 who were normal weight and 7 who were obese) and 14 control women (7 who were normal weight and 7 who were obese).


METHODS
A GHRH test (50 microg i.v.) and, on a different day, a GHRH test during a naloxone infusion (1.6 mg/h) during fasting. The same tests were repeated after a standard meal.


METHODS
GH response to GHRH (expressed as the area under the curve [AUC]) in different experimental conditions.


RESULTS
All normal-weight women showed a significantly higher AUC-GH compared with obese women in the fasting state. Normal-weight controls had a decrease in GH response to GHRH after feeding, and naloxone did not reverse the decrease. In obese controls, feeding increased the GH response but naloxone induced a decrease in the AUC. In fasting, normal-weight women with PCOS, naloxone significantly decreased the AUC-GH; in these patients, food intake induced an inhibition of GH response to GHRH, reversed by naloxone infusion. In obese PCOS patients, GH levels did not increase significantly after GHRH stimulation, either in the fasting state or after a meal, and naloxone did not affect these responses.


CONCLUSIONS
Factors other than obesity and insulin may be involved in disruption of GH secretion in women with PCOS.
Guido
Maurizio
M
Department of Obstetrics and Gynaecology, Università Cattolica del Sacro Cuore, Rome, Italy. maurizoguido@libero.it
Romualdi
Daniela
D
Mancini
Antonio
A
Lattanzi
Francesca
F
Villa
Paola
P
Barini
Angela
A
Lanzone
Antonio
A
De Marinis
Laura
L
D000328:Adult; D019540:Area Under Curve; D001835:Body Weight; D004435:Eating / Q000502:physiology*; D005215:Fasting / Q000502:physiology; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000627:therapeutic use*; D019382:Human Growth Hormone / Q000378:metabolism*; D006801:Humans; D009270:Naloxone / Q000627:therapeutic use*; D009292:Narcotic Antagonists / Q000627:therapeutic use*; D009765:Obesity / Q000150:complications / Q000473:pathology; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism*; D011446:Prospective Studies; D012016:Reference Values
D009292:Narcotic Antagonists; D019382:Human Growth Hormone; D009270:Naloxone; D013007:Growth Hormone-Releasing Hormone