Immunohistochemical distribution of glucagon -, insulin -, somatostatin -, gastrin-, and serotonin-containing cells in the pancreas of the Van cat

Abstract

The regional distribution, relative frequency, and appearance of glucagon (A-cell)-, insulin (B-cell)-, somatostatin (D-cell)-, gastrin (G-cell)-, and serotonin (EC-cell)-secreting cells in the endocrine and exocrine pancreas of Van cats were examined using the immunohistochemistry method. Glucagon immunopositive A-cells were principally found in the central region of the islets of Langerhans, while insulin immunopositive B-cells were located in the periphery of the pancreatic islets. Moreover, several A- and B-cells were observed as only single cells or clusters of 2 to 3 immunopositive cells in the exocrine parenchyma and the pancreatic duct epithelium. Somatostatin and gastrin immunopositive reactivities were negligible in the peripheral regions of the pancreatic islets of Langerhans and in the exocrine parenchyma. However, serotonin-immunopositive EC-cells were observed in neither the endocrine islets nor any other sites of the tissue. The existence, regional distribution, and relative frequency of A-, B-, D-, G- and EC-cells in the pancreas of Van cats have been analyzed in this study for the first time. The immunopositivity and distribution of endocrine cells in the Van cat pancreas were determined to be partially different from those of other carnivorous species such as dogs and other cats.