Hunger/Satiety's Physiopathologic Study in Morbidly Obese Patients

The mechanisms that regulate appetite in the morbidly obese are multifactorial and not well-known. Different peripheral signals (such as ghrelin or cholecystokinin) play an important role in the central regulation of appetite and hunger. Postprandial ghrelin and cholecystokinin (CCK) response has also an effect on gastric emptying that, in turn, has an effect on satiety sensation.

On the other hand, bariatric surgery is supposed to affect hunger and satiety in and also promotes changes in gastric emptying which are not clearly defined.

Aim: To better understand the physiologic mechanisms involved in the regulation of hunger and satiety in morbidly obese individuals, especially those related with gallbladder and gastric emptying, as well as those related with the response of the gastrointestinal hormones ghrelin, CCK and glucagon-like peptide-1 (GLP-1), before and after bariatric surgery (sleeve gastrectomy). Methodology: Three groups of individuals will be studied and compared: group A) non obese healthy subjects, group B) morbidly obese subjects and group C) morbidly obese subjects who had had a previous sleeve gastrectomy. In all subjects a standard meal test after a fasting night will be administered and appetite, satiety and hormonal response (ghrelin, CCK, GLP-1 and insulin) during 4 hours post-ingestion assessed, as well as postprandial gallbladder and gastric emptying by means of ultrasonography and the paracetamol absorption technique.