Centuries of interest in rats

Rats and mice are both rodent species; however, even though these two species have a similar appearance, there are significant differences between rats and mice as disease models. The primary focus of rat research is the species Rattus norvegicus which likely originated in Asia. The history of rats in biomedical research is quite extensive.  For over 150 years scientists have employed rats as models for many topics. In fact, the first domesticated laboratory mammal is believed to be the rat. 

Rat as a laboratory model system

Standardized animals for laboratory studies developed in a parallel way to that of mice. Henry Donaldson, a champion of rat research, created the initial stocks of albino rats with his team at the Wistar Institute and produced fundamental research using rat as a model system. Helen Dean King began inbreeding Donaldson’s rats in 1909. The first strain is known today as the King Albino or PA strain. Direct descendants of the Wistar collection rats continue to be available to researchers today.

Rats have certain advantages as models of disease, and they are one of the most widely used organisms in medical research.  Because rats are larger than mice, there are many areas of investigation for which they are easier to use than mice; for example, blood pressure measurements and serial blood samples are more readily obtained in rats than in mice.  Other crucial work in pharmacology, toxicology, nutrition, behavior and numerous other topics has been accomplished with rats.  The data from these various research initiatives form an excellent foundation and framework for many types of investigations of the impacts and treatments of cancer. 

Cancer research using rats as a model can be traced to the establishment of the Crocker Institute (later part of Columbia University) as early as 1912. Other institutes began to use the rat as a model for cancer studies as well. Subsequently numerous inbred rat strains were developed and actively used in cancer research.  A major long-term project employing rodents as a bioassay model for potential carcinogens has provided a wealth of data. The National Toxicology Program (NTP) has evaluated many compounds and agents of interest for the public health.

Rats on the leading edge

The National Cancer Institute, or NCI, has been supporting and developing resources for the investigation of cancer process, and exploration of therapeutic agents, using rat models for decades.  Ongoing projects such as the major CaBIG® initiative continue to provide a framework for employing animal models as one component of the translation of discovery to the clinic. Utilizing the resources and support provided by the NCI can benefit researchers by increasing the efficiency and effectiveness of their research.