Ultraviolet light-induced DNA repair synthesis in hepatocytes from species of differing longevities.

The DNA repair capabilities of cultured hepatocytes derived from five mammalian species in response to a broad range of ultraviolet light exposures were measured. Differences in the induction of DNA repair synthesis and the proportion of responding cells were noted only for the lowest fluences. These differences appeared to be positively correlated with the potential lifespans of the species involved; mouse and rat hepatocytes displayed less repair than those from guinea pig or rabbit. At higher fluence levels, however, there were no differences in the amount of repair induced. Thus the maximal repair potential of hepatocytes derived from the rat, mouse, hamster, guinea pig and rabbit were the same.