The effects of different protective methods with DHCA on neuron apoptosis in hippocampus / 中华胸心血管外科杂志

ABSTRACT

Objective: This study is to examine the effects of different protective methods with DHCA on neuron injury of hippocampus. Methods: Sixteen pigs (22-25 kg) were divided randomly into four groups. Group I DHCA; group II ACP; group III RCP; group IV RCP+Nim. All animals were under deep hypothemia (18℃) and total circulatory arrest for 90 minutes, and then rewarmed 120 minutes until the pharyneal temperature to 36℃. End of the study, left hippocampi were removed and then dissociated. These dissociated cells were stained with Annexin V-FITC and then measured with flow cytometry to analyze neuron apoptosis. The morphological changes were examined by electron microscope. Results: Normal cell percentage was the lowest in group I. Compared with group III, normal cell percentage was higher in group II. There were no significant differences between group II and group IV, or group III and group IV. Early apoptotic cell percentage was higher in group I than that in the other three groups, and it is higher in group II than that in group III. There were no significant differences between group II and group IV, or group III and group IV. Both necrotic cell percentage and dead cell percentage were higher in group I than that in the other three groups and there was no significant difference between the other three groups (P=0.05). Conclusion: Apoptosis, necroses and death of neuron after DHCA is the main cause of postoperative nervous dysfunction. ACP has better protective effect on neuron by decreasing cell apoptosis and death. RCP could also reduce cell apoptosis and death but the effect is not as good as that of ACP. Nimodipine depresses partly calcium influx by blocking up VDCC and its protective effect is slight.