Effect on acute rejection reaction and survival of the heart with the addition of dextran 60 to conventional immunosuppressive therapy in an experimental model of heterotopic heart transplantation

Background. Rejection reaction is an important complication in heart transp lantation. Recent physiopathological findings suggest new immunosuppressive alternatives such as the use of substances that block interaction between leukocytes and endothelium or subsequent events, The objective of this work was to evaluate the effect of the combination of dextran 60 and convention al immunosuppressive therapy. Methods. We used Sprague-Dawley rats, both se xes, with mean weight of 317.3 +/- 31.3 g on which we carried out heterotop ic heart transplantation and then randomized into four groups. All groups r eceived cyclosporine (2 mg/kg/day) and prednisone (0.5 mg/day). Group I (n = 5) also received 0.5 cc/kg/day of dextran 60, group II (n = 5) 1.0 cc/kg/ day of dextran 60, group III (n = 5) 2 cc/kg/day, and group IV (n = 4) 0.9% saline solution 0.5 cc/kg/day. The incidence and severity of rejection rea ction was evaluated as survival of transplanted hearts. Results. Significan t differences were found between groups III and IV for incidence of rejecti on reaction (p = 0.039). However, there were no differences among groups (g rade 3A or 3B) in the magnitude of the rejection reaction. Survival of hear ts was better in all groups receiving dextran 60 (p = 0.031). Conclusion. I t was concluded that dextran 60 improves survival of transplanted hearts: a nd decreases incidence of rejection reaction. (C) 2000 IMSS, Published by E lsevier Science Inc.