大鼠脑冷冻伤后脑组织NOS活性的变化

Alteration of brain NOS activity after cerebral cold-induced injury

目的研究大鼠脑组织冷冻伤后一氧化氮合酶（ＮＯＳ）活性的变化规律。方法利用液氮杯硬膜外冷冻大鼠顶叶脑组织复制冷冻伤模型，测定大鼠脑冷冻伤后不同时间脑组织ＮＯＳ活性。结果大鼠冷冻伤后３０ｍｉｎ局部脑组织ＮＯＳ活性增加（Ｐ＜０．０５），６０ｍｉｎ达较高水平（Ｐ＜０．０１），２ｈ有所下降（Ｐ＜０．０５），６ｈ左右再次升高，直至１２ｈ仍维持高水平（Ｐ＜０．０１）。结论表明大鼠脑组织冷冻伤后ＮＯＳ活性增高。

Objective To study the alteration of brain NOS activity after cerebral coldinduced injury in mice.Methods The rat model was induced by application of a liquid nitrogen copper cup on the intact dura of left parietal region for 10 seconds. We measured brain NOS activity of different time after cold injury.Resaults Compared with control group,the NOS activity of injured brain was increased as early as 30 min after cold injury(P<0.05),and reached a higher level at 60 min(P<0.01),decreased at 2h (P<0.05),then increased again at 6h and maintained at a high level at 12h(P<0.01).Conclusion The brain NOS activity was increased after cerebral coldinduced injury. Nitric oxide was an important factor in cold brain edema.