Glucose tolerance in the proximal versus the distal small bowel in Wistar rats.
BACKGROUND
Type 2 diabetes is an epidemic and insulin resistance is the central etiology of this disease. Obesity increases insulin resistance and glucose intolerance and also exacerbates metabolic abnormalities present in type 2 diabetes. Bariatric surgery is the most effective treatment for severe obesity. Most reported series show that return to euglycemia and normal insulin levels occur days after gastric bypass and biliopancreatic diversion, long before major weight loss has taken place. The mechanisms underlying this dramatic reversal of type 2 diabetes following these bariatric procedures are not well understood.


METHODS
Twelve Wistar rats were fed with a palatable hyperlipidic diet for 12 weeks. Body weight, glucose, and intraperitoneal glucose tolerance test were measured regularly. On day 91, they were randomized in two groups (hindgut and controls) and operated. Twenty-one days later, the tests were done again and the hindgut group re-operated. A duodenal exclusion was done. The results of an intraperitoneal glucose tolerance test were compared after the procedures.


RESULTS
Body weight increased regularly in all the rats. Some rats developed hyperglycemia 28 days after beginning hyperlipidic diet, but these levels returned to baseline on days 56 and 84. The glucose tolerance test showed an improvement in glycemic levels in the hindgut group 21 days after the first operation (151 +/- 21mg/dl). After the second operation, despite weight loss, the glucose tolerance test of the foregut group worsened again (267 +/- 53 mg/dl) (p < 0.01).


CONCLUSIONS
Comparing the "hindgut hypothesis" and the "foregut hypothesis", our data show an improvement in the 30 min glucose tolerance test in the hindgut group.
de Campos Martins
Marcus Vinicius Dantas
MVD
Department of Surgery, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. mvdantas@hotmail.com.|Estácio de Sá University, Rio de Janeiro, Brazil. mvdantas@hotmail.com.|, Av. das Américas 1981/64, Barra da Tijuca-Rio de Janeiro, CEP: 22631-000, Brazil. mvdantas@hotmail.com.
Peixoto
Antônio Augusto
AA
Department of Surgery, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Schanaider
Alberto
A
Experimental Surgical Center of the Department of Surgery, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Esposito
Christiano Costa
CC
Department of Surgery, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Aratanha
Carolina Barreira Albano
CBA
Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D004195:Disease Models, Animal; D018149:Glucose Intolerance / Q000150:complications / Q000175:diagnosis / Q000378:metabolism* / Q000601:surgery*; D005951:Glucose Tolerance Test / Q000379:methods; D007421:Intestine, Small / Q000378:metabolism* / Q000601:surgery*; D008297:Male; D009767:Obesity, Morbid / Q000150:complications / Q000378:metabolism / Q000601:surgery; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome
D001786:Blood Glucose