Distribution of endocrine cells in the gut of the impala (Aepyceros melampus).

Immunocytochemical methods were employed to demonstrate endocrine cells, containing peptides and serotonin, in the gut of the impala. Cells immunoreactive to serotonin, somatostatin, gastrin, cholecystokinin, glucagon, neurotensin, secretin, glucose-dependent insulinotropic peptide and motilin were detected. Antisera raised to substance P and pancreatic polypeptide failed to stain any cells. The distribution of these peptide-containing cells is more in line with the situation in sheep than other ruminants. In contrast, the distribution and abundance of serotonin cells in the gut of the impala parallels the situation seen in game herbivores.