| BackgroundMultifidus muscles is located in the innermost of spine and the area of the largest parspinal muscles,which also to maintain the spinal biomechanical balance and keep the stability of intervertebral joint segmental important pillar.And the multifidus muscles of the lumbosacral segment is particularly developed,especially in the multifidus muscles of L4-5 segments playing an more than 80%important role in keeping the dynamic stability of the lumbar spine.Once the lumbar multifidus muscles injuried,atrophy and function disordered,it is possible to cause lumbar instability and lead to low back pain.Acupuncture treatment of low back pain has a long history and curative effect affirmation."weizhong"(BL40)is a classic and effective acupuncture point of treatment of low back pain.Previous research has found that electroacupuncture at BL40 can improve the microcirculation after skeletal muscle injury,and the inflammatory response is an important node that affects the microcirculation after skeletal muscle injury,which plays an important role in the internal stablity of the damaged micro-environment.The degree of inflammation reponse is an important factor affecting cell injury,autophagy,apoptosis,necrosis and repair.It affects pathological trend and development directon of musle injury,which is very important for the repair of muscle injury.In this experiment,on the one hand,from the perspective of anatomy and histomor-phology to observe the morphological characterristics of the lumbar multifidus muscles;on the other hand,from the the perspective of the relationship between the inflammatory response and the steady state in microenvironment of the injury to observe and evaluate the effect of electroacupuncture at BL40 for the injury of multifidus muscle and part of the repair mechanism.Objective1.From the angle of anatomy to observe the morphological characteristics of multifidus muscles.And from the histomorphology of lumbar multifidus muscles injury after local fixed-point injected in 5%bupivacaine to observe the degree of muscle injury and the time course of musle recovery in rats.2.From the quantitative expression of IL-17 and LIF to investigate the effect of electro-acupuncture at "weizhong"(BL40)and "shenshu"(BL23)on the inflammatory response and repair process of lumbar multifidus muscles in rats and to discuss the possible mechanism of muscle tissue repair.MethodsExperiment 1:Sprague-Dawley rats multifidus muscles morphological anatomical observation.2 male SD rats(320-350g),only 10%chloral hydrate(350 mg/kg,ip)after injection of anesthetic rats,perfusion fixed,fixed satisfaction after exposed anatomical region,peel back fascia,blunt separation of adjacent muscle clearance,then walk along the muscle load-point and fiber line direction to blunt dissection,exposed multifidus muscles anatomical morphology,and high definition camera tracking for each segment crack more muscle anatomy,for morphological observation.Experiment 2:To observe the fixed point injection of lumbar multifidus muscles injury of rats model.18,male SD rats were randomly divided into:blank group,saline group,bupivacaine group,each group of six.Bupivacaine group rats,10%chloral hydrate anesthesia(350 mg/kg,ip),select the four points on both sides of the L4,L5 spinal level,the use of disposable syringeneedles(4)from 0.5%bupivacaine solution,the needle is 45 angle close to the spine to the torn muscle into more,come into contact with the joints and spine bone surface after back to the suction casing 1 mm bloodless,suggests that the needle has reached multifidus muscles,injection of bupivacaine 400 ml solution(4 points,per point about 100 ml),the time should not be less than 3 seconds,to facilitate the absorption of drugs.A single injection of bupivacaine to complete the building.Physiological saline injection method with the bupivacaine group.The blank group will not take any measures.After the completion of the building from the general behavior,the Angle of gait analysis and HE and Masson staining observation after building.Experiment 3:96 male SD rats(320-350g)were randomly divided into:the blank group(24),model group(24),electroacupuncture at "weizhong" group(24),electroacupuncture at"shenshu" group(24),each group and then were randomly divided into day 1,day 3,day 7 three subgroups,each subgroup 8 rats.10%chloral hydrate(350 mg/kg ip)after anesthesia,0.5%of bupivacaine solution(BPVC)by 100μl per point injection in the model group,"weizhong"group,"shenshu" group rats with bilateral level of L4-5(4)the lumbar multifidus muscles.Don’t make any deal with blank group.After the completion of the building,"weizhong" group and"shenshu" group were electroacupuncture therapy Respectively by optical microscope after HE staining groups of the lumbar multifidus muscles injury of rats in day 1,day 3,day 7 histomorphology changes;Using the immune-histochemical method and Elisa to detect each group rats the expression of IL-17 and LIF in day 1,day 3,day 7 after multifidus muscles injury,including comparison electroacupuncture at BL40 and electroacupuncture at BL23 on the model rats after injury of the role of inflammation and injury microenvironment steady state,including preliminary discussion including "weizhong" point and "shenshu" point the function of repair after lumbar multifidus muscles injury.Results1.From the result of general anatomical observations,the SD rats multifidus muscles has a lot of similarities with people multifidus muscles,both multifidus muscles in the spine most inside,and is one of the largest vertebral side muscle adhesion area,similar to a "Wire rope"from top to bottom lock the bony structure of the spine,to maintain spinal biomechanical balance,especially for spinal cord segmental stability play an important role.And cross L4,L5 segment of the longest length,the largest diameter,and have a tough membrane protection,powerful functions,for the proneness,after stretching and rotating motion of the lumbar spine and play an important role in maintaining the dynamic stability of lumbar spine.2.From the results of HE and Masson staining,the muscle fibers of the blank group were neat and uniform in size,and one or several nuclei were distributed in the muscle gap.After injection of saline,occasional mesenchymal cells slight edema,cell gap can be seen a small amount of damaged cells,less local inflammatory cell infiltration,but the muscle fiber arrangement is still neat,no obvious abnormal shape.And after injection of BP VC solution 24 hours later,we can see muscle cells have broken necrosis,atrophy,and the size of different,uneven arrangement,muscle gap with a large number of damaged cell debris,collagen fiber scattered distribution,and a large number of inflammatory cells were focal distribution.3.The effects of electroacupuncture at BL40 and BL23 on the expression of IL-17 and LIF after the rat’s multifidus muscle injury induced by the injection of BP VC.Compared with blank group at day 1,day 3,day 7,the expression of IL-17 in model group were higher than blank group(p<0.01);Compared with model group at day 1,day 3,day 7,the expression of IL-17 were decreased in "weizhong" group and "shenshu" group,and there are significant differences(p<0.01);the expression of IL-17 in "weizhong" group was lower than "shenshu"group at day 1(p<0.05),day 3(p<0.05),day 7(p<0.01);Blank group of LIF expression level is lower,after building,the expression of LIF levels was rised rapidly in model group,"weizhong"group and "shenshu" group;Compared with model group,"weizhong" group and "shenshu"group of LIF expression level increased at day 1,the difference was statistically significant(P<0.05,P<0.01);Compared with "shenshu" group,"weizhong" group expression level was increased at day 1(P<0.05);the expression of LIF was higher in "weizhong" group and"shenshu" group at day 3(P<0.05,P<0.01);Compared with "shenshu" group,the expression of LIF in "weizhong" group was increased(P<0.01);Compared with model group,the expression of LIF was higher in "weizhong" group and "shenshu" group at day 7(P<0.01,P<0.05);Compared with "shenshu" group,the expression of LIF in "weizhong" group was higher at day 7(P<0.05).Conclusions1.Across the L4-5 segmental multifidus muscles in SD rats,the length is the longest and diameter of the most and have a tough membrane protection,play an important role in maintaining the dynamic stability of the lumbar spine.2.The local fixed point injection of 5%bupivacaine can be copied successfully rat lumbar muscle damage model.Appeared after building local muscle fiber fracture,degeneration,necrosis,such as morphological changes,and in the micro damage to local environment with a large number of inflammatory cells infiltration,the degree of the inflammatory response in a timely manner is one of the important nodes affect skeletal muscle injury and repair pathologycal outcomes.3.Electroacupuncture on BL40 and BL23 could promote the morphological recovery of injuried multifidus muscle tissue.It is thanks to the onset time is earlier,the regulation is stronger and the action is longger,electroacupuncture on BL40 can promote early benign repair of multifidus muscle,which may be related to Electroacupuncture on BL40 could down-regulated the excessive expression of IL-17 and keep the moderate expression of LIF. |
