For many years, toxicological investigations have shown that the sensitivity of kidney to xenobiotics evolves depending on the stage of life. The increasing requirement for information on the potential nephrotoxic effect of drugs during human embryonic development, childhood, adulthood and senescence has potentiated toxicological studies in vivo. Rodents, specifically rats, are the primary animal models used in toxicology testing. Despite the popularity of this approach, there are a number of doubts about the appropriateness of rats for the examination of changes in toxicological responses during different stages of life. This perspective tackles the issue of evaluating whether rats fail to adequately mimic the human kidney response to xenobiotic agents through a critical analysis of the literature. We conclude that rats constitute a good model for toxicological investigations during embryonic development, youth and adulthood. However, senescent rats frequently undergo spontaneous kidney degeneration caused by chronic progressive nephropathy, making them a poor model for the study of kidney responses to xenobiotics.