Expression Of CNTFmRNA In Spinal Cord Injury And Effects Of CNTF On Spinal Cord Neurons

spiual cord injury has a serious consequence and has a serious mind andeconomic burden to patients and 8ociety How to recover nervous function is a focalpoint which medical specialist8 pay cIose attention to after SCI. Ciliary neurotrophicfactor(CNTF) has been shown to premote the survival of a variety of neurenal celltypes has including sensory neurons, motoneurens, sympathetic ueuron8 andparasympatketic neurens in vitrO and vivo.In this study we are intended to elucidate two problems. (l) Is CNTF invohed inthe response to spinaI cord injury? How is the expressionaI change of CNTFmRNA?(2) Does CNTF support the survival of injured spinal neurens, what is its possiblemechanism? Our aim is to explore how CNTF pIay the role on injured spinaI neurensin expetheental rats and pmide experimentaI basis for clinical heahaent of SCI.The main results are as fonows:l. Establiskment of spinal cord injury modelThe present study investigated the neuroprotectwe effects of CNTF in an AlIenweight drop model of spinal cord injury. Sprague-DawIey rats sustained a l0-gweight-drep injury to tke thoracic spinal cord (T8) from 5 cm. Catheter was installedin cavity beIow aracknoid membranae witk Yakih's method. CNTF or saline wasinjected in the cavity at the same time with same voIume. All indexes weredetermined according to tke experimental sckeme.2. Expressional changes of CNTFmRNA in injured spinal cordRNA extraction and RT-PCR were determined according to the specification ofreagent kits. RT-PCR preducts were electrephoresed in 1.5% agarose gel and theirdensity was assayed with computer. The results showed that the expression ofCNTFmRNA significantly increased compared with conhol group after SCI.3. 1nfluence of CNTF on the numher of neuren8, content8 of AckE and ACPTke rc8ult8 8howed that the numher of neuron8 in 8pinal cord wa8 8ignfficantlydecreas.d after SCL Tbe content of AchE wa8 distinctly decreased and the content ofACP was notably increased compared witb conbol poup. Administration or CNTFcould notably jncrea8e the number of neuron8, increase the cont6nt of AckE anddecrease tke content of ACP compared with 8aline greup.'. lnnuence of cNTF on tke content of water and ions in 8pinal cordThe mult8 8uggested that after SCI tke content of waten Na+, Ca2+ signtheantlyincreased and the content of K' Mgl+ notahly decrea8ed. Admini8tration of CNTFcould amenorate the spinal cord edema and reduce the ckange amputode of ion8compand with saline grOup.From aU above result8, 1t wa8 fOund tbat exPm8ion of CmmRNA upregUIatedafter SCI, whick 8uggest6d that CNTF wa8 invoIved in the 8pinal cord injurpAdministration of CNTF couId notahly increase the number of neurons, increase thecont6nt of Acan and decrease the content of ACP compared with 8ahoe greup, wkichshowed that CNTF could promote the survival of injured neurons. Furtkerinvestigating sugge8ted tkat te might pretect neuron8 via stabling tke balance ofintracelluar ion8 and extr8cenu1ar ions.