Cyclosporine in transplantation of the liver in the dog.

Orthotopic hepatic transplantation was performed upon 29 dogs. Four dogs received no immunosuppressant, 12 received cyclosporine and 13 received azathioprine. Dogs treated with cyclosporine at a dose of 20 milligrams per kilogram yielded histologic and functional data indistinguishable from those of the dogs in the sham transplant group. Histologic evidence of rejection consistently appeared when the dose was decreased to 10 milligrams per kilogram but was reversed upon resuming the administration of the higher dosage. Serum levels of bilirubin and hepatic enzymes, serum glutamic-oxalacetic transaminase, serum glutamic-pyruvic transaminase and alkaline phosphatase did not correlate with the development or resolution of histologic evidence of rejection in dogs receiving cyclosporine. Dogs receiving cyclosporine for 60 days had a prolonged survival when the drug was stopped, whereas the dogs receiving such therapy for less than 60 days did not have a prolonged survival period.