IMMUNOHISTOCHEMICAL IDENTIFICATION OF GALANIN AND LEUCIN-ENKEPHALIN IN THE PORCINE LACRIMAL GLAND

The presence and distribution of galanin (GAL) and leucine-enkephalin (LEU-ENK) in the pig lacrimal gland was investigated using immunohisto chemical techniques. Lacrimal gland segments obtained from the abattoi r were fixed in paraformaldehyde-picric acid solution, cut into 40-50 mu m thick sections and processed for immunohistochemistry using polyc lonal antisera against GAL and LEU-ENK. GAL- and LEU-ENK-immunoreactiv e intrinsic multipolar neurons were observed in the interacinar and in terlobular areas of the pig lacrimal gland. From these regions these i ntrinsic neurons send branches to the acinar and other tissues of the gland. Immunoreactivity was confined solely to the neural elements. Th ese two potent biologically active neuropeptides may play important ro les in the regulation of lacrimal fluid secretion.