| IntroductionNeurofilament(NF) which is complicated and special is a kind of intermediate filament of cytoskeleton. Axon cytoskeleton is consisted of NF mostly, while soma cytoskeleton is consisted of Microtubule (MT) and NF. It is different from other interfilaments because it exists with Microtubule closely. Not only does it support the shape of the cells, but also takes part in the activities, such as the transportation of the substance, energy exchanging, cell differentiation, cell conversion, distribution of the organelles and the signal conduction etc. All these are very important to the cells. Nerofilament contacts with the plasma membrane, the nucleus surface and the nucleus stroma, also with the microtubule, microfilament and the organelles, just like a whole net system spreading in the plasma.SDS electrophoresis shows that; NFPs fell into three groups; 200KD,160KD,68KD, called NF-H,NF-M,NF-L respectively. The recombination of the three kinds of proteins by immuno-EM has shown that P68 polymerizes the main stem, P200 and PI60 construct the side chains by twisting main stem in a spiry manner. The quantity of NF-H is ten times over the other two in axon, which is the factor to control the diameter of axon. From the point of developing biology, NF-L andNF-M are presented in nerve system firstly, after that is NF-H. NF-H indicates the neuron is mature. NF-H can strengthen the structure of the axon, because there are cross bridges between NFs or NF and MAPs. It is researched because of its representativeness.NLY has a close relationship with the functions of neuron. Because the substance can not be synthesized in axon, NLY takes charge of the task to make the neuron have sufficient nutrient by axoplasmic transmission. But the relations between NF and NLY and the functions of NF have not been understood clearly.Traditionally, researchers think NLY has relations with MT, but not with NF because NLY has been changed after using MT-depolyme-rization drug. But this kind of drug has also destroyed NF simultaneously. Somebody confirmed the structure of interfilament has been changed after using colchicine.In order to confirm that NF has effect on NLY, vanadate was used because it can depolymerize NF firstly. Vanadate is a kind of small molecule and easy to penetrate membrane. Low concentration of it acts as insulin in the second messenger aspect. Also it is a inhibitor of tyrosine phosphatase and a kind of drug used to treat the diabetes in clinical research. It can make NF over phosphorylated, depolymerize NF into small molecules and effect the whole structure.In this experiment, we observe the changes and the characteristics of NF-H from the beginning to the mature time. By using vanadate to observe the disorder of NF-H and the distribution of NLY, suspect the relationship between the depolymerization of NF-H, calcium iron and the process of signal transmission cross the membrane, and deduce the machanism.At present, researchers focUs their attentions on three-diMentionstructure of NF, model of DNA and gene structure. The function of NF nas not teen known clearly. If the integrity of NF has been confirmed important to substance transportation, especially about NLY, all these will throw light on the research about regressional diseases of nervous system.materials and method1. The developmental characteristics of NF-HWe used the newborn Wistar rats about 1 day for primary culture. Spinal cords were taken and were isolated by trypsin perfusion, cultivated in Dulbecco's modified Eagle's medium ( DMEM) supplemented with 10% fetal bovine serum, 100u/ml penicillin, 100ug/ml streptomycin, 10mM HEPES at 37T1 in 5% CO2-air atmosphere. The cells were allowed to adhere onto rat tail glue coated glasses or Tefulong diaphragm at a density of 10 x 105 cells/ml and cultivated for 5, 7, 9, 11, 13 days respectively before the experiment. Immunocytochemis-try; after rinsing the glass with Hank's fluid, fix it with cold acetone for 5 min, following it is 1% Triton X-100 for 10 min. Use norma...
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