An Immunohistochemical Study of Endocrine Cells in the Alimentary Tract of the Red-bellied Frog, Bombina orientalis.

Abstract

ABSTRACT. The regional distribution and relative frequency of endocrine cells was studied immunohistochemically (PAP method) in the alimentary tract of the red-bellied frog, Bombina orientalis, using antisera against serotonin, somatostatin, chromogranin (CG), cholecystokinin (CCK)-8, bombesin, secretin, glucagon and pancreatic polypeptide (PP). Eight kinds of endocrine cells were identified in this study. These immunoreactive cells were located in the gastric glands of the stomach regions and in the intestinal or esophageal epithelium with variable frequencies. They were spherical or spindle-shaped. Serotonin-and somatostatin-immunoreactive cells were demonstrated in the whole alimentary tract including esophagus. CG-immunoreactive cells were restricted to the stomach. CCK-8-immunoreactive cells were observed from the antrum to the ileum. Bombesin-immunoreactive cells were restricted to the stomach. Secretin-immunoreactive cells were demonstrated in the pylorus, duodenum and ileum. Glucagon-immunoreactive cells were found in the antrum and duodenum. PP-immunoreactive cells were detected from the antrum to the rectum. In conclusion, throughout the alimentary tract of the red-bellied frog, the different regional distribution and relative frequency of endocrine cells were demonstrated. The regional distributions and relative frequencies of the endocrine cells in the alimentary tract of the red-bellied frog were resembled to those of the other anuran species except for esophagus.-KEY WORDS: alimentary tract, endocrine cell, immunohistochemistry, red-bellied frog.

Histochemical, immunohistochemical, and ultrastructural observations of the esophagus morphology of Rinella icterica (Anuran, Bufonidae)

“…Most amphibians produce more pepsinogen in the esophagus when compared with that of the stomach (Vonk 1964). The regional distribution and relative frequencies of 5-HT-immunoreactive cells were detected in the esophageal epithelium of A. regularis (El-Salhy et al 1981), L. catesbeinus (Nada et al 1984), and Bombina orientalis (Ku et al 2000). Serotonin (5-hydroxytryptamine, 5-HT) is a widespread aminergic component of secretory granules in the diffuse gastro-enteropancreatic (GEP) neuroendocrine system of mammals and lower vertebrates, where it is co-stored and co-secreted with specific corresponding hormones (Maake et al 2001), neuropeptides (D'Este et al 1994Trandaburu and Trandaburu 2007), and granin proteins (Lee and Ku 2004).…”

“…According to the current concept, GEP organs represent the second major source of 5-HT after the central nervous system and are also important targets for this monoamine (Frazer and Hensler 1999). The regional distribution and relative frequencies of 5-HT-immunoreactive cells were detected in the esophageal epithelium of A. regularis (El-Salhy et al 1981), L. catesbeinus (Nada et al 1984), and Bombina orientalis (Ku et al 2000). According to those previous reports, cholecystokinin (CCK), glucagon, and gastrin-producing endocrine cells did not occur in the esophageal mucosa and were not similarly observed in the esophagus of R. icterica.…”

“…Extensive studies have been carried out to analyze the endocrine cell ontogeny and distribution in several mammalian species (Eerdunchaolu et al 2001;Ku et al 2003b;Machado-Santos et al 2009). In the esophageal mucosa serotonin, somatostatin and cromogranin were detected in A. regularis (El-Salhy et al 1981), L. catesbeianus (Nada et al 1984), Pelophylax ridibundus (formerly Rana esculenta), (D'Este et al 1994), and Bombina orientalis (Ku et al 2000). In the esophageal mucosa serotonin, somatostatin and cromogranin were detected in A. regularis (El-Salhy et al 1981), L. catesbeianus (Nada et al 1984), Pelophylax ridibundus (formerly Rana esculenta), (D'Este et al 1994), and Bombina orientalis (Ku et al 2000).…”

“…Nevertheless, information about the occurrence of enteroendocrine cells in the amphibian esophagus is still scarce. In the esophageal mucosa serotonin, somatostatin and cromogranin were detected in A. regularis (El-Salhy et al 1981), L. catesbeianus (Nada et al 1984), Pelophylax ridibundus (formerly Rana esculenta), (D'Este et al 1994), and Bombina orientalis (Ku et al 2000). According to animal species and feeding habits, the distribution of endocrine cells varies along the digestive tube.…”

Immuno histochemistry of gastrointestinal ehdocrine cells in the meckel's diveiticulum of the bean goose,anser fabalislatham

“…In all vertebrates so far investigated secretin-immunoreactive cells proved to be exclusive to the small intestine, usually with preference for the duodenum and upper jejunum (Solcia et al, 1989;Baltzar et al, 1998;Ku et al, 2000). However, no data were available in the been goose.…”