Gastrin immunoreactive cells in the gastrointestinal tracts from four species of fish

Abstract

Using antiserum against human gastrin, we have demonstrated cross reactivity in endocrine cells from the gastrointestinal tracts of four fish species (Ambloplites rupestris, Lepisosteus osseus, Lepomis gibbosus, and Percaflavescens). In the corporic stomach, positive cells were found in the surface and glandular epithelium and subepithelial connective tissue of A. rupestris but only the surface and glandular epithelium of L. gibbosus whereas no immunoreactive cells were found in either L. osseus or P. flavescens. In the pylorus of A. rupestris and P. flavescens, immunoreactive cells were few in number in the surface epithelium but numerous in the underlying lamina propria. In the pylorus of L. osseus and L. gibbosus, no positive cells were seen in the lamina propria but in the former a few were present in the surface epithelium. In intestine of A. rupestris, L. gibbosus, and P. flavescens immunoreactive cells were present in both surface epithelium and subepithelial connective tissue. Possible explanations for the notable species differences are discussed.