REINNERVATION OF PANCREATIC TISSUE AND ISLET GRAFTS BY AMINERGIC, CHOLINERGIC AND PEPTIDERGIC NERVES - A REVIEW

A brief history of the discovery of insulin and pancreatic tissue tran splantation was given including the events that led to the introductio n of pancreatic transplantation. This was followed by a detailed accou nt of the different sites used in pancreatic tissue fragment and islet transplantation, and the fate of the grafts. Reinnervation of these p ancreatic islet and tissue grafts have received little attention since pancreatic transplantation started in 1892 and it became apparent tha t only a couple of investigators have actually embarked on the systemi c studies of the presence of different neurotransmitters and neuromodu lators in the nerves reinnervating pancreatic islets and or fragments transplanted into different sites in the mammalian body. The nerves re innervating pancreatic tissue and islets can be grouped into intrinsic or extrinsic nerves. The intrinsic nerves are the intrapancreatic neu rons that survived and produced or stored neurotransmitters after tran splantation. The extrinsic nerves are novel to the transplant and orig inate from the mixed nerve plexuses of the site of transplantation. Th ese extrinsic nerves are carried into the transplant by the brood vess els revascularizing the pancreatic islet or tissue graft. The pattern of reinnervation by extrinsic nerves is depicted in diagrams.