An immunohistochemical study of endocrine cells of the alimentary tract of the King's skink (Egernia kingii).

The gastrointestinal tract of the King's skink (Egernia kingii) was examined for the presence of fifteen regulatory peptides, two proteinases and an amine by immunohistochemical methods. Immunoreactivity was detected for somatostatin, gastrin, motilin, bovine pancreatic polypeptide, pepsinogen and serotonin, but not for avian pancreatic polypeptide, gastric inhibitory peptide, secretin, cholecystokinin, enteroglucagon, pancreatic glucagon, gastrin-releasing polypeptide, neurotensin, vasoactive inhibitory polypeptide, leu-enkephalin or chymosin. The six peptides detected in E. kingii have been previously found in the gastrointestinal tract of squamate reptiles; however, immunoreactivity for other peptides previously detected in squamates, in particular another skink, was not observed. In addition, chromogranin was found to be effective in the detection of endocrine cells though its specificity was unknown.