Regional and mucosal distributions of some intestinal immunoreactive endocrine cells in New Zealand white rabbit (Oryctolagus cuniculus L.)

The aim of this study was to detect the regional and mucosal distribution of endocrine cells that secrete gulcagon, somatostatin, Chyholecystokinin-8 (CCK-8), serotonin, secretin, substance P (SP) and histamine in the small and large intestine of New Zealand white rabbit (Oryctolagus cuniculus L.) using immunohistochemical peroxidase-antiperoxidase (PAP) method. It was found that most of the immunoreactive (IR) endocrine cells, which are oval- or spindle-shaped, are spotted in the basal parts of the relevant glands. It was noticed that cells in the lamina epithelialis of small and large intestine is linked to the lumen and that the cells in their glands cannot reach the lumen. Immunoreactive cells for glucagon, somatostatin, serotonin, secretin and SP were identified in lamina epithelialis of the small and large intestine. It was seen that secretin, SP and histamine-IR cells are rarely deployed throughout the intestinal tract. It was determined that somatostatin-IR cells were identified throughout the intestinal tract. In conclusion, the immunohistochemical study shows that gastrointestinal tract of this species contained different types of endocrine cells similar to those found in other vertebrate species. However, some species-dependent unique distributions and frequencies of endocrine cells were also observed in the present study.