Effect of vasopressin on hippocampal injury in a rodent model of asphyxial cardiopulmonary arrest.

The effect of vasopressin on the neuronal injury following the restoration of spontaneous circulation (ROSC) in cardiac arrest (CA) is not yet fully understood. The present study was conducted in order to investigate the effect of vasopressin alone, or in combination with epinephrine, on the ROSC and hippocampal injury in a rat model of asphyxial CA. Asphyxial CA was induced in 144 rats by clamping the tracheal tube, and animals were allocated equally into the following three groups: Treatment with vasopressin (0.8 U/kg); epinephrine (0.2 mg/kg); or vasopressin (0.8 U/kg) plus epinephrine (0.2 mg/kg). An additional 48 rats underwent a sham surgical procedure without asphyxial CA and cardiopulmonary resuscitation. Hippocampal tissue was harvested at 1, 3, 6 and 12 h post-ROSC, and the levels of p38 mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) p65 were determined using immunohistochemistry. In comparison with rats treated with epinephrine alone, higher ROSC success rates were observed in rats treated with vasopressin, or vasopressin plus epinephrine. In addition, treatment with vasopressin attenuated hippocampal injury and reduced hippocampal p38 MAPK and NF-κB expression more efficiently compared with epinephrine alone. In conclusion, treatment with vasopressin exhibits a protective effect in patients experiencing CA, and this may be attributed to the inhibition of p38 MAPK and NF-κB expression.