Immunodetection of cocaine- and amphetamine-regulated transcript in bovine pancreas.

This study was aimed at identifying and determining the configuration of structures which contain the cocaine- and amphetamine-regulated transcript peptide (CART) in the bovine pancreas. The study material was collected from 20 animals. The distribution of CART in the bovine pancreas was investigated, by an immunohistochemical evaluation. CART peptide in the normal pancreas has been identified in intrapancreatic ganglia, nerve fibres and in endocrine cells of Langerhans islets and exocrine pancreas. CART immunoreactive nerve fibres innervate the exocrine and endocrine regions and the intrapancreatic ganglia, where they form a moderate number of networks, encircling the cell bodies. The few CART-immunoreactive endocrine cells, that appear in the bovine pancreas, are not limited to the islet cells, where they form a subpopulation of CART-containing cells, but are also individually distributed in the exocrine region. Furthermore, CART has been visualized in nerve fibres, innervating pancreatic outlet ducts and blood vessels. CART plays a physiological role in the integrated mechanisms that regulate both endocrine and exocrine pancreatic secretion. These results are consistent with the hypothesis that CART expression in nerve fibres and intrapancreatic ganglia is a common feature of the mammalian pancreas, whereas its expression in endocrine cells appears to be restricted to single cells of the bovine pancreas.