An immunohistochemical study of endocrine cells in the alimentary tract and pancreas of the toad, Bufo bufo gargarizans Cantor

두꺼비(Bufo bufo gargarizans cantor)에서 위장췌내분비세포의 면역조직화학적 연구

  • Lee, Hyeung-sik (Department of Biology, Faculty of Natural Science, Kyungsan University) ;
  • Ku, Sae-kwang (Pharmacology & Toxicology Lab., Central Research Laboratories, Dong-Wha Pharm Ind. Co.) ;
  • Park, Ki-dae (Department of Histology, College of Veterinary Medicine, Kyungpook National University) ;
  • Lee, Jae-hyun (Department of Histology, College of Veterinary Medicine, Kyungpook National University)
  • 이형식 (경산대학교 자연과학부 생물학전공) ;
  • 구세광 ((주)동화약품 중앙연구소 약리독성연구실) ;
  • 박기대 (경북대학교 수의과대학 조직학교실) ;
  • 이재현 (경북대학교 수의과대학 조직학교실)
  • Received : 1999.12.28
  • Published : 2000.03.25

Abstract

The regional distribution and relative frequencies of endocrine cells were studied immunohistochemically (PAP methods) in the alimentary tract and pancreas of the toad, Bufo bufo gargarizans Cantor using specific antisera against bovine Sp-1/chromogranin (BCG), serotonin, bombesin, gastrin, substance P (SP), somatostatin, insulin, glucagon, pancreatic polypeptide (PP), vasoactive intestinal polypeptide (VIP) and secretin. Nine kinds of endocrine cells were identified in this study. Spherical or spindleshaped immunoreactive (IR) cells were located in the gastric glands of stomach regions, in the basal portion of the epithelium of intestinal tract or esophagus, and in the exocrine or pancreatic islets with variable frequencies. In the alimentary tract, BCG-IR cells were found in the fundus and pylorus with rare and a few frequencies, respectively. Serotonin-IR cells were demonstrated in the whole alimentary tract including the esophagus. Bombesin- and SP-IR cells were restricted to the stomach regions and gastrin-IR cells were restricted to the pylorus. Somatostatin-IR cells were detected throughout the whole alimentary tract except for the large intestine, However, insulin-, glucagon-, PP-, VIP- and secretin-IR cells were not detected in the alimentary tract. In the pancreas of toad, the distribution and relative frequency of endocrine cells were similar to those of other mammals. Insulin-IR cells were located in the central portion of the pancreatic islets and interspaces of exocrine portions, and glucagon-, somatostatin- and PP-IR cells were detected in the marginal regions of the pancreatic islets and interspaces of exocrine. However, other IR cells were not found in the pancreas. In conclusion, the regional distribution and relative frequency of the endocrine cells in the alimentary tract and pancreas of the toad were similar to other anuran species but some differences which might be caused by feeding habits and species specification were also observed.