针刺对脊髓Clarke核突触性终末可塑性的影响

用单侧后肢备用根猫,针刺手术侧(实验组)与不针刺者(对照组)各5只,于30天时在电镜下比较腰3段Clarke核的终末数。结果实验组和对照组的非手术侧三类突触性终末的数量差别无显著性,表明针刺对对侧无明显影响;实验组手术侧背根来源的巨大终末较对照组明显增多,并恢复到非手术侧水平,而非背根来源的两类终末数与对照组差别无显著性,表明针刺对完好背根,主要为备用背根粗髓纤维的侧枝出芽与突触重建的可塑性变化有明显地促进作用,而对非背根的神经纤维却无明显影响。

The Effect of Acupuncture on Plasticity of Spinal Clarke's Nucleus Synaptic Terminals

Ten unilateral spared rootcats with sectioned L_1-S_2 dorsal root gan-glia, except L_6, were used to explore theeffect of acupuncture on plasticity of spi-nal Clarke's nucleus synaptic terminals.Five of the cats were needled on the ope-rated hind limb for two courses (ten daysas a course), and the other five werekept for control. Two pairs of acupointslocated in the innervated area of L_6 spinalnerve were used. The number of synapticterminals per photo in neuropil of L_3Clarke's nucleus was compared directly,because there was no significant changein the area of Clarke's nucleus and itsneuropil on the operated side of bothgroups. No significant difference was foundin the number of three types of synapticterminals between the unoperated sides oftwo groups, suggesting that acupuncturemay not influence the contralateral side.In the control group, the number of giantaxonal terminals from dorsal root of theoperated side decreased to 75% of the un-operated side; however, in the experimen-tal group, it recovered to contralateralor normal level of the operated side andwas significanly higher than that of thecontrol group's operated side, denoting.that acupuncture may promote the plasti-city such as collateral sprouting and syn-aptic reinnervation of coarse myelinatedfibers from intact dorsal root, L_6 mainly.The number of other two types of termi-nals from spinal interneurons showed nosignificant difference between the operatedsides of two groups, indicating that acu-puncture may not enhance the plasticityof nondorsal root nerve fibers.