A Rodent Model of Adjustable Gastric Band Surgery—Implications for the Understanding of Underlying Mechanisms

Obesity Surgery (Impact Factor: 3.1). 05/2009; 19(5):625-631. DOI: 10.1007/s11695-008-9751-0

ABSTRACT BackgroundBariatric surgery is currently the only anti-obesity therapy that can deliver weight loss of up to 20–30% of body weight.
Laparoscopic adjustable gastric banding (LAGB) and Roux-en-y gastric bypass are the most commonly performed of these surgeries.
The mechanisms by which LAGB initiates an increase in satiety remain completely unknown. The aim of this study is to establish
a rodent model of adjustable gastric banding (AGB) that will enable investigation of these mechanisms.

MethodsSprague–Dawley rats were implanted with adjustable gastric bands immediately below the gastro-esophageal junction around the
glandular stomach. This band, as in humans, can be inflated via an exteriorized port resulting in an incremental impact on
the stomach.

ResultsRats with an incremental inflation of the AGB showed a clear stepwise reduction in food intake and body weight. Normal food
intake and body weight gain were restored with band deflation. Barium-assisted X-ray of the stomach showed the formation of
a small gastric pouch proximal to the inflated band in a manner analogous to the human LAGB.

ConclusionsThis is the first animal model of the AGB that allows incremental inflation for optimal tightening of the band in the conscious
animal with corresponding effects on food intake and body weight. This model will allow measurement of acute and chronic neural
and hormonal changes following activation of the band in the conscious animal and will provide the potential to inform and
improve surgical approaches that are at the forefront of obesity treatments.

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