Stress and murine sarcoma virus (Moloney)-induced tumors.

Stable stress-responsive models have been established in murine (Moloney) virus sarcomas, which lend themselves to further study of intervening immunological mechanisms. Maximum tumor size was increased in sex-segregated male BALB/c mice at 6 and 9 months of age and in females subjected to 3 days of electric shock stress following virus inoculation. Reduction in maximum tumor size was found in females shocked for 3 days prior to virus inoculation. Similarly, females that spontaneously showed fighting behavior developed smaller tumors. Possible endocrine and immunological factors contributing to these varied stress effects are discussed.