旋磁场对大鼠脑缺血再灌注时TXA_2-PGI_2和自由基代谢的影响

Effects of Rotating Magnetic Field on Metabolism of Free Radicals and TXA 2 PGI 2 during Cerebral Post ischemic Reperfusion in Rats

用四血管阻断法造成大鼠全脑缺血０５ｈ后，再灌注０５ｈ时，大鼠脑组织和血浆过氧化脂质（ＬＰＯ）、血栓素Ｂ２（ＴＸＢ２）含量及ＴＸＢ２／６ｋｅｔｏ前列腺素Ｆ１α（６ｋｅｔｏＰＧＦ１α）比值明显增高，而６ｋｅｔｏＰＧＦ１α含量却无明显变化。如在大鼠脑缺血０５ｈ后开始再灌注时，用００８Ｔ、２５００ｒ／ｍｉｎ的旋磁场作用于双侧颈动脉区２０ｍｉｎ，大鼠脑组织和血浆ＬＰＯ含量、ＴＸＢ２／６ｋｅｔｏＰＧＦ１α比值明显降低，但ＴＸＢ２和６ｋｅｔｏＰＧＦ１α含量无明显变化。脑急性缺血再灌注损伤中自由基增多，血栓素Ａ２－前列环素（ＴＸＡ２－ＰＧＩ２）代谢平衡失调，ＴＸＡ２作用较ＰＧＩ２相对增强。旋磁场能降低自由基水平，调节ＴＸＡ２－ＰＧＩ２代谢平衡，对防治脑急性缺血再灌注损伤有一定作用。

The complete cerebral ischemia (CCI) models were made by 4 vessel occlusion in Wistar rats. By 30 min recirculation after 30 min CCI in rats, brain tissue and plasma levels of lipid peroxidation (LPO) and thromboxane B 2 ( TXB 2,metabolite of thromboxane A 2 ) increased ( both P<0.05), and the ratio of TXB 2/6 keto PGF 1α (6 keto PGF 1α , metabolite of prostacyclin) also increased (P<0.05), but the change of 6 keto PGF 1α was not significant (P>0.05).At the beginning of reperfusion in brain tissues after 30 min CCI in rats,rotating magnetic field ( RMF, 0.08T,2500r/min) was used by placing it on bilateral carotid areas for 20 min. RMF could decrease LPO levels and TXB 2/6 keto PGF 1α ratio in brain tissues and plasma (all P<0.05), but had no significant effects on values of TXB 2 and 6 keto PGF 1α ( all P>0.05). During acute cerebral post-ischemic reperfusion, free radicals(FR) values increased, the balance of TXA 2-PGI 2 broke,effects of TXA 2 is stronger than that of PGI 2. Because the effects of RMF can decrease FR levels and make TXA 2 PGI 2 balance,It is concluded that RMF has protective effects on brain from post ischemic reperfusion injury.