Homograft reaction in mice: effect of urethane and sublethal x-radiation.

Combined treatment of mice with urethane (a nucleic acid antagonist and mitotic inhibitor) plus sublethal x-radiation (500 rad) suppresses the homograft response to a degree considerably greater than that observed with this dose of x-rays alone. Thus, LAF(1) mice receiving two injections of urethane plus 500 rad of x-radiation prior to grafting retained C(3)H mouse skin grafts for periods up to 60 days, with a mean graft survival time of 40 days, as compared with 18 days for mice exposed to 500 rad only.