Abstract: Identification and localization of gastrointestinal hormone endocrine cells in the digestive tract of Eleutheronema tetradactylum were carried out by using immunohistochemistry method of Strept Avidin-Biotin-Complex, six types of antisera raised against rabbit hormones such as 5-hydroxytryptamine(5-HT), somatostatin(SS), gastrin(GAS), glucagon(GLU), neuropeptide Y(NPY) and cholecystokinin(CCK-8). The results showed that the immunoreactive cells could be divided into open type endocrine cells and enclosed type endocrine cells by morpha. No positive cells were detected in the esophagus. The gastrin(GAS) and somatostatin(SS) positive cells were detected in the stomach, but the GAS cells were confined to the pylorus with less density. Plenty of SS positive cells were detected in sections of the stomach, SS cells were detected only in pyloric caeca, GAS cells were found only in foregut, no any positive cells detected in midgut, and GAS and SS cells could be found in hindgut. No any of 5-HT, GLU, NPY and CCK-8 immunoreactive cells was detected throughout the digestive tract. The speculative endocrine pattern and physiological functions of this species were discussed.

Key words: Eleutheronema tetradactylum, digestive tract, gastrointestinal hormone, endocrine cells, immunohistochemistry