The effect of vertical banded gastroplasty on glucose-induced beta-endorphin response.
BACKGROUND
beta-Endorphin is an endogenous opioid involved in the regulation of food intake and obesity as well as in insulin metabolism. In this study, we investigated glucose-induced beta-endorphin, insulin, and glucose responsiveness in morbidly obese patients and the effect of surgically induced weight loss.


METHODS
Thirty-two healthy, nondiabetic, morbidly obese patients (body mass index over 40 kg/m2) and 32 normal-weight controls were studied. Serum levels of beta-endorphin, insulin, and glucose were measured under basal conditions and during an oral glucose tolerance test (OGTT) before and 12 months following vertical banded gastroplasty.


RESULTS
Preoperative basal levels of beta-endorphin, insulin, and glucose and their responses during OGTT in obese patients were significantly higher compared with those of controls. After surgery, basal beta-endorphin, insulin, and glucose levels decreased significantly compared with preoperative values. Postoperative basal insulin and glucose levels were similar to those in controls, while beta-endorphin levels remained significantly higher than those of controls. A significant reduction in total responses of beta-endorphin, insulin, and glucose during OGTT was also observed; however, postoperative beta-endorphin and insulin responses remained significantly higher than in controls.


CONCLUSIONS
Morbidly obese patients have an increased glucose-stimulated response of beta-endorphin, insulin, and glucose which is partially corrected with weight loss following vertical banded gastroplasty.
Karayiannakis
A J
AJ
First Department of Internal Medicine, University of Athens, Athens, Greece.
Syrigos
K N
KN
Zbar
A
A
Makri
G G
GG
Athanasiadis
L
L
Alexiou
D
D
Bastounis
E A
EA
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D016022:Case-Control Studies; D005260:Female; D015391:Gastroplasty / Q000379:methods*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D009767:Obesity, Morbid / Q000097:blood* / Q000473:pathology / Q000601:surgery*; D013997:Time Factors; D015431:Weight Loss; D001615:beta-Endorphin / Q000097:blood*
D001786:Blood Glucose; D007328:Insulin; D001615:beta-Endorphin