INHIBITION BY GALANIN OF EXPERIMENTAL CARCINOGENESIS INDUCED BY AZASERINE IN RAT PANCREAS

The effects of galanin on pancreatic carcinogenesis induced by azaseri ne and on the norepinephrine concentration in the pancreas were invest igated in male Wistar rats, Rats were given weekly injections of 10 mg /kg body weight of azaserine for 25 weeks and 8 mu g/kg body weight of galanin in depot form every other day for 62 weeks. Azaserine-induced pancreatic lesions were examined with hematoxylin and eosin and histo chemical techniques. In week 62, quantitative histological examination showed that prolonged administration of galanin significantly reduced the number and size (as percent of parenchyma) of adenosine triphosph atase-positive pancreatic lesions, which are correlated closely with t he ultimate development of pancreatic cancer. The number of pancreatic adenocarcinomas in rats treated with galanin was significantly less t han in controls. Galanin also significantly decreased the bromodeoxyur idine-labeling index of azaserine-induced pancreatic lesions and the n orepinephrine concentration in the pancreas. Our findings indicate tha t galanin inhibits pancreatic carcinogenesis and that such inhibition may be related to the suppression of sympathetic nervous system activi ty and subsequently to the inhibition of cell proliferation in neoplas tic lesions of the pancreas. (C) 1998 Wiley-Liss, Inc.