Potentiating effect of beta-aminopropionitrile on the DNA synthesis induced by isoproterenol

Young mice chronically treated with beta-aminopropionitrile (BAPN) were subsequently given injections of graded doses of isoproterenol, and the response of various tissues to IPR in synthesizing DNA was analyzed. The results indicate that chronic administration of BAPN potentiates the effect of IPR for inducing DNA synthesis in the parotid, submandibular gland, kidney, and urinary bladder. The effect of BAPN was most pronounced in the submandibular gland. Namely, acinar cells in the submandibular gland normally respond less to IPR than do those in the parotid but respond more when mice have been treated with BAPN. It was suggested that the structural modification of collagen may counteract the blockage of events leading to DNA synthesis in epithelial cells in vivo.