The rapid cooling contracture in myocardial protection is getting more and more attention. Rapid cooling contracture is referred to as the undepolarized myocardial contracture induced by rapid cooling, which is related with the sudden increase of Ca2+. The Ca2+ released from sarcoplasmic reticulum subsequently causes myocardial contracture through the myofilaments sliding. Its deleterious effects include: more energy consumption, impaired cardiac function, Ca2+ overload, et al. And some investigators have put forward some principals to prevent the bad influences of rapid cooling contracture.

Objective To explore the inhibitory effect of L-arginine on cardiac allograft vasculopathy (CAV) and its possible mechanisms.Methods The rat cardiac allograft model was used. In the control group (n=26), L-arginine was not administered after heterotopic cardiac transplantation, and the other 21 rats (experimental group) received administration of L-arginine ( 800?mg/kg every day, in drinking water) after heart transplantation. CAV score was evaluated and plasma nitric oxide (NO) was measured at 2 and 3 months after transplantation. Results Graft survival rate 2 months after transplantation was significantly (P