caa a22 4500 475774418 CHVBK 20180406123627.0 cr unu---uuuuu 170329e20000801xx s 000 0 eng 10.1007/s004180000169 doi (NATIONALLICENCE)springer-10.1007/s004180000169 Development of hormonal peptides and processing enzymes in the embryonic avian pancreas with special reference to co-localisation [Elektronische Daten] [Benjamin B. Rawdon, Lars-Inge Larsson] Abstract.: Studies on the developing mammalian pancreas have suggested that insulin and glucagon co-exist in a transient cell population and that peptideYY (PYY) marks the earliest developing endocrine cells. We have investigated this in the embryonic avian pancreas, which is characterised by anatomical separation of insulin and glucagon islets. Moreover, we have compared the development of the endocrine cells to that of processing enzymes involved in pancreatic hormone biosynthesis. PYY-like immunoreactivity occurred in islet cells from the youngest stages examined: it increased in amount from approximately 5days of incubation and was co-localised with glucagon and to a lesser extent with insulin. Insulin and glucagon cells were numerous: co-existence of the two peptides in the same cells was but rarely observed. From the youngest stages examined, prohormone convertase (PC) 1/3-like immunoreactivity was detected in insulin cells and PC2-, 7B2- and carboxypeptidaseE-like immunoreactivity in both glucagon and insulin cells. We conclude that: (1) PYY-like immunoreactivity occurs in avian islet cells but generally in lesser amounts than in mammals at the earlier stages, (2) the paucity of cells co-expressing insulin and glucagon indicate that all avian insulin cells do not pass through a stage where they co-express glucagon and (3) the early expression of the enzymes responsible for the processing of prohormones suggests that this process is initiated soon after islet cells first differentiate. Springer-Verlag, 2000 Chick embryo Immunocytochemistry Islets of Langerhans Pancreatic development PeptideYY Prohormone convertases nationallicence Rawdon Benjamin B. Department of Anatomy and Cell Biology, Faculty of Health Sciences, University of Cape Town, Observatory, 7925, South Africa aut Larsson Lars-Inge Division of Cell Biology, Department of Anatomy and Physiology, Royal Veterinary and Agricultural University, Gronnegaardsvej 7, 1870 FrederiksbergC, Denmark aut https://doi.org/10.1007/s004180000169 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004180000169 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rawdon Benjamin B. Department of Anatomy and Cell Biology, Faculty of Health Sciences, University of Cape Town, Observatory, 7925, South Africa aut NATIONALLICENCE 700 1- Larsson Lars-Inge Division of Cell Biology, Department of Anatomy and Physiology, Royal Veterinary and Agricultural University, Gronnegaardsvej 7, 1870 FrederiksbergC, Denmark aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer