EFFECTS OF STRESS ON THE GROWTH OF A FIBROSARCOMA IN NU-NU AND CONVENTIONAL MICE

BALB/c mice subjected to water stress twice daily, between 3 and 7 min at each exposure 3 days before, 5 days after, or 3 days before and 5 days after intradermal Meth A tumour transplantation, showed an increase of tumour size and tumour growth rate compared with that of home cage control (HCC) mice. However, BALB/c mice subjected to water stress 3 days before and 6 days after tumour transplantation showed a decrease of tumour size and tumour growth rate compared with HCC mice. BALB/c mice subjected to 2 min of handling stress daily on days 1 through 5, but not BALB/c mice subjected to handling stress on days 1 through 7 or on days 6 through 7 of tumour growth, showed an increase in tumour size relative to HCC mice. On the other hand, BALB/cBy mice handling stressed on days 1 through 7, but not BALB/cBy mice handling stressed on days 1 through 5 or days 6 through 7 after tumour transplantation, showed a decreased tumour size compared with HCC mice. No effect of stress could be observed when nu/nu BALB/c mice were subjected to water stress 3 days before and 6 days after tumour transplantation. However, BALB/c nu/nu mice pre-injected intraperitoneally with spleen cells from conventional mice had a decreased tumour size and growth rate of the tumour when stressed 3 days before and 6 days after tumour transplantation.