[Acupoints specificity in promoting the plasticity of cat spinal lamina II with acupuncture-quantitative EM study]

Our previous studies have shown acupoints stimulation might promote the plasticity of spinal cord. In order to explore the acupoints specificity of the effects we used ten cats with unilateral dorsal partial rhizotomy (L1-S2, except L6). The rhizotomy sides of five cats received acupuncture stimulation (acupoints stimulation group) at Zusanli (St36), Xuanzhong (GB 39), Futu (St32) and Sanyinjiao (Sp 6) in the innervated areas of L6 spinal nerve for two courses, 10 days per coure. The rest cats were subjected to needling at the areas adjacent to the acupoints (nonacupoints stimulation group). Quantitative EM method was applied to detect (the population of synaptic terminals in lamina II 30 days postoperation. According to the number of synaptic contacts between synaptic terminal and postsynaptic element, synaptic terminals were divided into two types: the simple terminal (ST) coming from spinal and descending tract, and the complex terminal (CT) from dorsal root. The average numbers of the two types' synaptic terminals per photo were compared directly because the acupoints and nonacupoints groups' transverse areas of lamina II showed no significant difference. The results showed: (1) There was no significant difference for ST number between two groups. Associated with our previous study that acupoints stimulation did not influence ST number, the present result indicated that nonacupoints stimulation had no effect on ST number, (2) The complex terminal numbers were statistically different (P < 0.05). The percentage of CT in the nonacupoints group was only 53% of that in the acupoints group. This result was similar to two other nonacupuncture groups in our laboratory (the percentages were 59% and 62% respectively). It indicates that the effect of nonacupoints stimulation is similar to that of nonneeding, i.e. nonacupoints stimulation does not promote the plasticity of spinal lamina II or there might be acupoints specificity in promoting the plasticity of spinal laminal II.