Influence of L-arginine on hypoxia-ischemia brain injury in dogs after circulatory arrest and resuscitation / 解放军医学杂志

ABSTRACT

Objective To study the effects of deep hypothermia and L-arginine(NO precursor) pretreatment on cerebral protection after circulatory arrest and resuscitation in a canine model. Methods Ten healthy adult dogs of both sexes, weighing 14.45?2.3kg, were randomly divided into two groups(n=5): sham treatment group and L-arginine pretreatment group. Extracorporeal circulation was established routinely,circulatory arrest was induced when the nasopharyngeal temperature was reduced to 18℃, then the animals were resuscitated 90min later with extracorporeal circulation. SjvO2 was measured at 30min before circulatory arrest, 0min, 45min, 90min after circulatory arrest and at 60minutes after resuscitation. The ultrastructure changes in cerabral cortex were observed with transmission electron microscope (HITACHI 7500). The brain water content was also determined after the dogs were sacrificed. Results SjvO2 had decreased obviously after circulatory arrest, attaining the lowest level in CA 90min.After resuscitation it increased again in both groups. The levels of SjvO2 in dogs of L-arginine pretreatment group were markedly higher than that of control group at 45min and 90min after circulatory arrest (P