Behavioral parameters in rats and mice bearing tumors, carcinogens and inflammatory agents in the brain.

Walker tumor cells and carcinogens were implanted into the brains of rats and L1210, P388 and Ehrlich ascites tumors, in addition to inflammatory agents and hydrocarbons, injected cortically into mice. Behavioral changes were followed in such animals by several psychological criteria, a discriminated lever-press task in rats and an exploratory task, the poke test, in rats and mice. An activity wheel was also employed for further amplification of mouse behavior. No definite changes could be discerned by these tests between rats bearing tumor or carcinogen and the respective controls as was also the case with levels of activity in the mouse. In marked contrast, mice administered tumors or kaolin cortically demonstrated significant reductions in the mean number of pokes, especially with the higher numbers of cells injected and where neurological symptoms were evident. Behavioral changes, if any, were minimal in mice with cortically implanted carcinogens.