The immunohistochemical localization of the glycosphingolipid asialo-GM1 in the intestine of weaned piglets.

The duodenum, jejunum, ileum, cecum and colon of three male hybrid piglets, 4 weeks old just after weaning, were investigated for the immunohistochemical localization of the asialoganglioside, GM1 (asialo-GM1). The study revealed various degrees of labelling for this acid glycosphingolipid in neural, epithelial and blood elements in all the gut segments. The immunolabelled neural structures, represented by ganglionic perikarya and nerve fibers, were distributed throughout the intestinal wall and showed quantitative variations in the various regions.

The immunohistochemical localization of synaptophysin protein (p38) in the gastro-entero-pancreatic (GEP) system of reptiles.

The gastro-entero-pancreatic (GEP) system of four reptilian species: turtle (Emys orbicularis), lizards (Lacerta viridis and Lacerta agilis) and snake (Natrix natrix) has been investigated immunohistochemically for the presence and topographic distribution of synaptophysin. Among the studied reptiles, only in turtles were neural, glial and neuroendocrine elements labelled for this marker protein. Semi-quantitative evaluation of the immunolabelled neural structures distributed throughout the gastroenteric wall revealed, with two exceptions, highly significant mean differences between the successive gut segments.

Serotonin (5-hydroxytryptamine, 5-HT) immunoreactive endocrine and neural elements in the chromaffin enteropancreatic system of amphibians and reptiles.

The diffuse chromaffin enteropancreatic system of nine species of amphibians (newts, frogs) and reptiles (turtles, lizards, snakes) was investigated immunohistochemically for the presence and topographic distribution of serotonin (5-hydroxytryptamine, 5-HT). The study revealed various numbers of serotonin-producing cells in the pancreas and intestinal epithelium and also immunolabelled nerve profiles in the villi of all species studied. In addition, two different morphological populations of serotonin cells ("open" and "closed") were localized in the functional segments of the intestines in the representative species of all the taxa investigated.

Granin proteins (chromogranin A and secretogranin II C23-3 and C26-3) in the endocrine pancreas of amphibians.

The occurrence and cellular distribution of chromogranin A (CgA) and of two synthetic secretogranin II (SgII)-fragments (termed C23-3 and C26-3) has been investigated immunohistochemically in the endocrine pancreas of five amphibian species. Immunoreactivity for CgA was detected only in specimens of the genus Rana, whereas for SgII it was found in all the urodeles and anurans studied. Either CgA or the SgII-fragment displayed its own cellular distribution patterns in the endocrine pancreas of a given species.

Granin proteins (chromogranin A and secretogranin II C23-3 and C26-3) in the endocrine pancreas of reptiles.

The endocrine pancreas of four reptile species belonging to the turtles, lizards and snakes was investigated immunohistochemically for the occurrence and cellular distribution of chromogranin A (CgA) and of two synthetic secretonin II (SgII)-peptides (C23-3 and C26-3). CgA-immunoreactivity was found only in the turtle pancreas, whereas that for SGIIC23-3 appeared both in the turtle and snake. None of the species studied displayed immunoreactivity for SgIIC26-3.