不同温度与持续时间下射频热凝对兔半月神经节的组织学影响

Effects of radiofrequency thermocoagulation on trigeminal ganglions in rabbits

目的研究不同温度与持续时间下射频热凝对兔半月神经节的组织学影响。方法利用R-2000B型温控热凝射频仪和外裸长50mm，直径0．4mm热敏电极，对80只兔半月神经节分别进行60、70和80℃温控热凝毁损实验，于术后第1、7、14和28天取出受损的半月神经节，HE染色阳性者，按石蜡切片热修复抗原实验程序行免疫组化检测，观察毁损后神经丝蛋白（NF200）、乙酰胆碱酯酶（ACHE）及毒蕈碱乙酰胆碱酯酶受体（M受体）表达情况。结果毁损半月神经节HE染色阳性表现为神经节细胞退变，神经纤维分布不均匀，髓鞘脱失。免疫组化结果为：NF200阳性表现为神经节细胞胞质和神经纤维细胞胞质内见深棕黄色颗粒，ACHE阳性表现为神经节细胞胞质和神经纤维细胞胞质内见深棕黄色颗粒，M受体阳性表现为神经节细胞胞质和神经纤维细胞胞质内见棕黄色颗粒。同一温度下，射频持续时间相同时，随术后时间的增加，NF200、ACHE、M受体三项指标的阳性表达率逐渐增高；而射频持续1min与3min比较，三项指标阳性表达率差异均无统计学意义（均P〉0．05）。射频持续时间相同时，70℃与60℃比较，三项指标阳性表达率均明显降低，差异均有统计学意义（均P〈0．05）；而70℃与80℃比较，三项指标阳性表达率差异均无统计学意义（均P〉0．05）。结论当射频毁损温度为70℃左右时，对半月神经节杀伤力最大，神经活性明显降低；这可能是半月神经节毁损的较适宜的温度。

Objective To study the histological effects of different temperatures and durations of radiofrequency on the trigeminal ganglions in rabbits. Methods Trigeminal ganglions of 80 rabbits were treated by R-2000B RF thermocoagulation at 60, 70, 80℃ respectively and the thermal electrode of 50 mm long and 0.4 mm in diameter. The treaded trigeminal ganglions were removed for HE （hematoxylin ＆ eosin） dying at Days 1,7, 14 and 28. And the expressions of neurofilament protein （ NF200）, acetylcholinesterase （ACHE） and muscarinic receptors （M-receptor） were observed after an immunohistochemical detection of HE positive samples. Results The positive manifestations of HE were degeneration of trigeminal ganglionic cells, the distribution of nerve fibers and a loss of myelinic membrane. The positive features of immunohistochemistry were as follows： NF200： dark yellow-brown particles within cytoplasm of ganglionic cells and nerve fibers ceils ; ACHE ： deep yellow-brown particles within cytoplasm of ganglion cells and nerve fibers cells; M-receptor： yellow-brown particles within cytoplasm of ganglionic cells and nerve fibers cells. The expressions of NF200, ACHE and M-receptor increased while the temperature and radio frequency time remained constant. There was no significant difference between the expression rates of NF200, ACHE, M receptor at the same temperature for 1 and 3 minutes （P 〉 0. 05）. When treated for the same time, the expressions of NF200, ACHE and M receptor decreased more significantly at 70℃versus 60 ℃ （ P 〈 0. 05）. However, there was no significant difference between 70 ℃ and 80 ℃ （P 〉 0. 05）. Conclusion 70 ℃ may be a suitable temperature at which radiofrequency causes the greatest harm to trigeminal ganglions so that nerve activity decreases significantly.