Cadherins, being responsible for selective cell recognition and normal tissue integrity in adults, regulate morphogenesis in a variety of organs during development. In this study, anti-rat pan-cadherin antibody, specific to all subgroups of the cadherin family, was used to map the distribution of the pan-cadherin immunoreactivity in adult rat organs. Pan-cadherin immunoreactivity positive tissues were: secretory cells of the adenohypophysis, autonomic nerve, corneal epithelium, oesophageal nerve plexus, stomach and pyloric glandular cells, epithelium of the ileum and its nerve plexus, alveolar cells of the lung, proximal convoluted tubules of the kidney, islet cells of Langerhans, and the acinar cells of the exocrine pancreas. For the first time, positive pan-cadherin immunoreactivity was demonstrated in the epithelial cells of the corpus ciliaris and in the nerve plexus of corpus cavernosum of the penis. In conclusion, our results suggest that cells in many tissues and organs of the adult rat synthesize cadherins. (C) 2002 Elsevier Science Ltd. All rights reserved.