A novel surgical technique focused on the study of the ileum: The preduodenal ileal transposition

Aims

Our main goal is to study the effects on the carbohydrate metabolism. Thus, we designed various experimental surgical models on healthy non-obese Wistar rats to reproduce several conditions. In this sense, we report a new experimental model. It is well known that bariatric surgery has important effects on the control of Type 2 Diabetes Mellitus. The underlying reasons are yet unknown, although the different theories focused in the release of different hormones after the pass of the nutrients through the tract. These released hormones have opposite effects that come together in a balanced glycemic metabolism.

Materials and methods

After bariatric surgical techniques, the modified anatomy resulted in an imbalance of the secreted hormones. Wistar rats were randomized in two groups Sham and surgical group. Our model consisted on the transposition of the terminal ileum right after the pylorus. Weight gain, food intake, and basal glycemia were measured weekly.

Results

We did not obtain significant differences between both groups for these functional variables.

Conclusions

This technique involved an early pass of the bolus through the ileum. The change on the luminal pH, along with the lack of enzymes to absorb the content, or the changes in the release of several hormones must be variables to the study. The mortality rate was assumable considering it was an experimental model on animals.

The main participation of the enterohormone GLP-1 after bariatric surgery

BACKGROUND

Numerous hypotheses are called to explain the beneficial effect on glucose metabolism after bariatric surgery. Some authors advocate for the secretion and release of various substances with endocrine functions for the explanation on this event. One of the substances most marked as effector, with contrasting effects but controversial data, is GLP-1.

METHODS

Our study was performed in healthy male Wistar rats, to avoid the absence of confounding factors such as T2DM and obesity. In order to know the adaptation of GLP-1 secretion after surgery 5 groups were designated: two control groups (fasting and surgical stress), and three surgical groups (gastric sleeve, 50% resection of the midgut and the Roux en Y gastric bypass). After three months the GLP-1 synthesis in the different portions of the small intestine and the expression of the membrane receptors in pancreatic islet cells were studied by immunohistochemical techniques.

RESULTS

There was a significant increase in the number of secretory cells in ileum, duodenum and jejunum in mixed (RYGB) and malabsorptive (RI50) surgical groups. An elevation of pancreatic receptors signal was also observed in the same techniques versus controls.

CONCLUSIONS

Our data indicate that intestinal secretion of GLP-1 and its sensitivity to the pancreatic changes were increased like a response of an adaptive effect to the mechanical aggression of the digestive tube and as alteration of nutrient flow after surgery.