The pharmacology of immunosuppressant drugs in skin transplant rejection in mice and other rodents.

1. Skin transplantation in rodents is a convenient, widely used method, particularly in mice. It is used as much as an indicator of immune responsiveness as for pharmacological studies. 2. Many differences exist in experimental protocols, both for transplantation and drug administration and in this review, the increase in graft survival time with respect to control times is used to indicate drug effects, in an attempt to account for these differences. 3. The mechanisms underlying skin graft rejection in rodents are described, emphasising the crucial role of both helper and effector T cells. 4. The pharmacology of clinically-used immunosuppressants, including CsA, FK506, rapamycin and purine or pyrimidine synthesis inhibitors, in rodent models of skin transplantation is reviewed. 5. The effects of other potential immunosuppressants and compounds modulating immune responses are described, including the effects of UV light and involvement of platelet-derived factors, prostaglandins and thromboxanes.