Does jejunal feeding activate exocrine pancreatic secretion?
Continuous feeding in the distal jejunum does not stimulate exocrine pancreatic secretion but maintains gallbladder contraction, although to a lesser extent. These effects are not related to hormonal changes but probably reduced activation of the enteropancreatic reflexes.
While there is an excess of G?C-->A?T changes in the rpoB gene, this was not the case in the pncA gene. Fifty-three percent of mutations within the rpoB gene were C-->T mutations of the type S531L. Although this mutation gives a fitness disadvantage, it is less than other common mutations, so it is more likely that that fitness is the determinant of surviving mutation rather than oxidative stress because of the small numbers of other C-->T and G-->A mutations at other sites (12%). There was no evidence of oxygen free radicals damaging the guanine bases in either gene.