We sought to examine insulin-sensitive food intake behavior and neuroendocrine and metabolic variables of rats that had undergone a duodenal-jejunal bypass (DJB).
A DJB that circumvents the duodenum and proximal jejunum while leaving the stomach unperturbed rapidly improves insulin sensitivity in type 2 diabetic rats. This segment of proximal small intestine is innervated by the gastroduodenal branch of the vagus nerve, the transection of which influences food intake choices in streptozotocin-diabetic rats.
Rats were first placed on a choice of chow and lard for 7 days and additionally provided with an enriched liquid diet for another 7 days before surgery and were allowed only the liquid diet for 7 days after either a sham or DJB operation.
After surgery, DJB-operated rats initially consumed less than the sham-operated counterparts. When the rats were subsequently provided with the choice of chow and lard for 7 days, there were no differences in intake between the DJB and sham-operated groups. Similarly, the majority of metabolic and neuroendocrine variables measured were unchanged. However, DJB-operated rats exhibited greater mesenteric white adipose tissue weight, fecal output, arcuate nucleus neuropeptide Y mRNA expression, plasma corticosterone, and glucagon levels together with reduced plasma leptin concentrations.
DJB surgery does not produce significant differences in food intake choices after a period of recovery; however, there are enduring metabolic and neuroendocrine changes, which are collectively important to understanding the beneficial outcomes of the operation.
A duodenal-jejunal bypass in rats causes a transient weight loss followed by a subsequent weight gain, although no catch up growth. We examined food intake choices and showed importantly no difference in total calories or the proportion of lard and chow consumed by DJB operated rats, despite changes observed in circulating hormones and hypothalamic neuropeptides.
From the Departments of *Physiology and †Surgery, University of California San Francisco, San Francisco, CA.
This work was supported, in part, by NIH grants DK28172 and DA16944.
Reprints: James Warne, PhD, Department of Physiology, Box 0444, University of California San Francisco, 513 Parnassus Ave, San Francisco, CA 94143. E-mail: firstname.lastname@example.org.