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BACKGROUND:Mesencephalon-derived neural stem cells(NSCs)differentiate into dopaminergic neurons in hypoxia and transgenic condition with body culture morphology and function of adequate maturity of dopamine neurons.Mesencephalon-derived NSCs become ideal seed cells for the treatment of Parkinson's disease with the rapid development of stem cell transplantation in the past few years.OBJECTIVE:To review research progress of mesencephalon-derived NSCs transgene for treating Parkinson's disease.METHODS:PubMed database was retrieved in computer(1992-01/2006-12),with the key words of "Neural Stem Cell(NSC),Mesencephalic Neural Stem Cell(M-NSC),Neural Stem Cell Transplant,Parkinson's Disease(PD)".Simultaneously,China Journal Full-Text Database(2003-01/2008-12)was retrieved with the same key words.RESULTS AND CONCLUSION:The NSCs and in the basic research of M-NSCs and M-NSCs transplantation in the treatment of PD-related documents were selected.A total of 83 documents were collected.Following reading titles and abstracts,14 studies with irrelative objectives and contents,16 studies with repetitive contents and 53 articles of Meta analysis were excluded.Totally 47 literatures were included.The main pathologic changes of Parkinson's disease are a dopaminergic neuron degeneration of necrosis in the brain substantia nigra.Using genetically modified neural stem cells in treatment of Parkinson's disease is the most recognized as the most promising treatment.In the hypoxia conditions,transgenic culture of brain-derived neural stem cells can be effectively induced to differentiate into dopaminergic neurons,provide experimental basis for in vitro sufficient amount of dopamine neuron transplantation in the treatment of PD.Basic research of neural stem cells have achieved certain results,but clinical and experimental study of neural stem cell transplantation in the treatment of PD is still stuck in the laboratory stage.Mesencephalic neural stem cell biological characteristics,isolation,proliferation and differentiation are subject to further study.In addition,biological safety problems using mesencephalic neural stem cells in the human body gradually attracted the attention of the people.In vitro neural stem cells of many passages would occur,and will bring certain side effects,and tumorigenicity remains in further exploration.
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BACKGROUND: The effect of external application of capsaicin in the treatment of superficial pain has been recognized, but its effect against trigeminal neuralgia by direct action on the nerve ending or nerves in the hypodermis or deep tissues awaits intensive investigation.OBJECTIVE: To observes the effect of subcutaneous injection of capsaicin on calcitonin gene-related peptide (CGRP) and nitric oxide synthase(NOS)-positive nerve fibers in rat facial skin.SETTING: Teaching and Research Division of Anatomy, Xianning Medical College, and Department of Neurobiology, Tongji Medical College of Huazhong University of Science and Technology.MATERIALS: This experiment was conducted in the Laboratory of Neurobiology, Tongji Medical College, between October and December 2003.Twenty healthy Wistar rats of either sex with body mass of 120-170 g were used.METHODS: The rats received subcutaneous injection of capsaicin for treatment of the suborbital branch of the trigeminal nerve on the right side,with the left side serving as the control side. According to the doses of capsaicin applied, the rats were divided into 4 groups, namely 20, 30, 50and 100 μL capsaicin groups with 5 rats in each group. Twenty-four hours after the injections, samples were obtained and cut into slices for microscopic observation and the expressions of CGRP and NOS were examined immunohistochemically.MAIN OUTCOME MEASURES: [1] Changes of CGRP and NOS-positive nerve fibers on the experimental side and image analysis of the mean absorbance of CGRP and NOS; [2] changes of characteristic behaviors and body signs of the rats.RESULTS: Totally 20 rats entered the result analysis. [1] Behavioral change: A few minutes after subcutaneous injection of capsaicin, the rats exhibited a series of characteristic behavioral and symptomatic changes,which gradually diminished or even vanished with the increase of the doses. [2] Microscopic changes: On the experimental side, no obvious difference was noted in the expression of CGRP and NOS-positive nerve fibers between the groups. [3] Imaging analysis of the mean absorbance of CGRP and NOS: For CGRP, the mean absorbance was 0.984±0.056 on the control side and 0.947±0.025, 0.852±0.042, 0.756±0.028 and 0.730±0.016 in 20,30, 50 μL and 100 μL capsaicin groups, respectively. As for NOS, the mean absorbance was 0.151±0.009 on the control side, and was 0.148±0.007,0.132±0.012, 0.111±0.067 and 0.107±0.006 in 20, 30, 50 μL and 100 μL capsaicin groups. Analysis of variance revealed significant differences between the groups (P ＜ 0.01).CONCLUSION: CGRP and NOS participate in the processing of nociceptive information and modulate pain and analgesia. Capsaicin executes analgesic effect by exhausting massive neurotransmitters.
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0.05).Conclusion CAP infiltration at trigeminal nerve infraorbital branch region in rats can produce stronger analgesic effect,it related to the dosage,concentration,using dosage, time and intermission.