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11.
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目的研究吗啡依赖和戒断时大鼠杏仁核中神经甾体和氨基酸递质水平的变化。方法连续7天给予大鼠盐酸吗啡建立吗啡依赖模型。使用纳洛酮(2mg/kg)催促戒断,观察戒断症状并进行评分。将大鼠断头处死后,剥离大脑并分离出杏仁核,用液-液萃取和固相萃取法提取游离型和结合型神经甾体。神经甾体(包括脱氢表雄酮、孕烯醇酮、别孕烯醇酮、脱氢表雄酮硫酸酯和孕烯醇酮硫酸酯)的含量使用高效液相色谱-质谱法测定。甘氨酸、谷氨酸和γ-氨基丁酸的含量采用柱前OPA衍生-电化学检测-高效液相色谱法测定。结果与盐水对照组相比,吗啡依赖大鼠杏仁核中的脱氢表雄酮水平降低33 %(P<0·01)。与戒断对照组比较,吗啡戒断大鼠杏仁核中的孕烯醇酮和别孕烯醇酮水平分别升高45 %和42 %(P<0·05) ,γ-氨基丁酸水平降低18 %(P<0·01)。与吗啡依赖组比较,吗啡戒断组大鼠杏仁核中的孕烯醇酮和孕烯醇酮硫酸酯水平分别升高60 %和40 %(P<0·05) ,甘氨酸水平降低14 %(P<0·05)。结论吗啡依赖大鼠杏仁核中的脱氢表雄酮可能参与吗啡依赖的形成而与吗啡戒断症状的表达无关。其他神经甾体(包括孕烯醇酮、别孕烯醇酮和孕烯醇酮硫酸酯)则可能参与吗啡的戒断而与依赖的形成无关。纳洛酮催促戒断时,大鼠杏仁核中抑制性氨基酸递质的合成和释放受到抑制。表明大鼠杏仁核中的各种神经甾体和氨基酸递质在吗啡依赖和戒断时发生了不同的变化。 相似文献
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J. Viac C. Goujon L. Misery V. Staniek M. Faure D. Schmitt A. Claudy 《Photodermatology, photoimmunology & photomedicine》1997,13(3):103-108
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response. 相似文献
15.
J. Carleson P. Kogner I. Bileviciute E. Theodorsson A. Appelgren B. Appelgren S. Kopp N. Yousef T. Lundeberg 《Archives of oral biology》1997,42(12):869-876
Temporomandibular joint (TMJ) arthritis was induced in female Lewis rats by unilateral injection of a suspension of heat-killed Mycobacterium butyricum in paraffin oil into the TMJ. Control rats received paraffin oil by the same route. Arthritic and control rats were pretreated either with capsaicin or denervation of the mandibular branch of the trigeminal nerve. Tissues were collected for neuropeptide extraction and analysed by radioimmunoassay and reverse-phase high-performance liquid chromatography. In all groups, the levels of substance P- (SP), calcitonin gene-related peptide- (CGRP) and neuropeptide Y- (NPY) like immunoreactivity (LI) were higher in the trigeminal ganglia than in the TMJs. In control rats, capsaicin significantly lowered the levels of SP-LI in the trigeminal ganglia and TMJ, but not CGRP-LI and NPY-LI. In the arthritic rats, capsaicin pretreatment significantly lowered the SP-LI and CGRP-LI in the trigeminal ganglia and TMJ, but not the NPY-LI. In the trigeminal ganglia the unilateral denervation significantly lowered SP-LI in control rats, and in arthritic rats SP-LI and CGRP-LI. On the denervated side of the arthritic TMJ, NPY-LI, SP-LI and CGRP- LI were significantly lowered as compared to the arthritic control rats and to the contralateral side. In this rat model, pretreatment with capsaicin and surgical denervation decreased the neuropeptide content in the trigeminal ganglia and the TMJ. The results clearly demonstrate a close interaction between increased neuropeptide release from sensory and sympathetic neurones after induction of arthritis in the rat. 相似文献
16.
Jim Orford Lorna Templeton Asmita Patel Richard Velleman Alex Copello 《Drugs (Abingdon, England)》2007,14(2):117-135
Background: This is the second of two papers using qualitative methods from a study of an intervention for family members affected by close relatives' substance misuse problems.
Participants: 168 primary healthcare professionals (PHCPs: GPs, practice nurses and health visitors) working in general practices in two areas of England, and who took part in the study.
Data sources: Recruitment and post-session forms completed by PHCPs; telephone interviews with each PHCP 12 weeks after recruitment of a family member; interviews with PHCPs at the end of the study.
Results: At the end of the project PHCPs were overwhelmingly positive about the family member intervention and about primary care as the appropriate site. Difficulties were encountered, however, in identifying and engaging affected family members, who were often excluded on grounds of the complexity of their problems or the level of their distress. Shortage of PHCP time and other practice-related factors added to the difficulty. Active work by a PHCP was often necessary in order to make the link between presenting symptoms of physical or mental ill-health and the existence of a family substance misuse problem. When family members were identified and recruited, PHCPs were usually positive about what was achieved. Nearly all were in favour of an approach that combined giving a self-help manual with some follow-up contact with a family member as needed.
Conclusions: Taken in conjunction with statistical outcome findings of significant reductions in symptoms and changes in ways of coping, plus qualitative analysis of the views of family members, the present results encourage the view that a flexible form of this intervention should be developed for use in primary healthcare, and that further work should build on existing strengths and attempt to overcome weaknesses identified. 相似文献
Participants: 168 primary healthcare professionals (PHCPs: GPs, practice nurses and health visitors) working in general practices in two areas of England, and who took part in the study.
Data sources: Recruitment and post-session forms completed by PHCPs; telephone interviews with each PHCP 12 weeks after recruitment of a family member; interviews with PHCPs at the end of the study.
Results: At the end of the project PHCPs were overwhelmingly positive about the family member intervention and about primary care as the appropriate site. Difficulties were encountered, however, in identifying and engaging affected family members, who were often excluded on grounds of the complexity of their problems or the level of their distress. Shortage of PHCP time and other practice-related factors added to the difficulty. Active work by a PHCP was often necessary in order to make the link between presenting symptoms of physical or mental ill-health and the existence of a family substance misuse problem. When family members were identified and recruited, PHCPs were usually positive about what was achieved. Nearly all were in favour of an approach that combined giving a self-help manual with some follow-up contact with a family member as needed.
Conclusions: Taken in conjunction with statistical outcome findings of significant reductions in symptoms and changes in ways of coping, plus qualitative analysis of the views of family members, the present results encourage the view that a flexible form of this intervention should be developed for use in primary healthcare, and that further work should build on existing strengths and attempt to overcome weaknesses identified. 相似文献
17.
本文试图阐明不同情期大鼠血浆神经降压素含量的变化。血浆神经降压素以无水乙醇提取后采用放射免疫分析法测定。间情期、动情前期和动情期大鼠血浆内神经降压素样免疫活性物质的含量依次分别为92.1±7.7ng/L,118.0±9.4ng/L 和144.3±10.2ng/L。动情期大鼠血浆神经降压素样免疲活性物质的含量较间情期大鼠有极显著差异(P<0.01)。 相似文献
18.
目的探讨胶质细胞活化对慢性前列腺炎/慢性盆腔疼痛综合征(chronic prostatitis/chronic pelvic pain syndromes,CP/CPPS)大鼠脊髓背角P物质的影响。方法完全福氏佐剂和3%角叉菜胶前列腺内注射造成CP/CPPS模型,脊髓插管给药胶质细胞活化抑制剂Propentofylline干扰CP/CPPS模型大鼠,免疫组织化学方法观察正常组、疼痛模型组、药物干扰组脊髓节段(L6和S1)背角的胶质细胞的活化和P物质的定性定位,并用放射免疫的方法观察三组脊髓背角P物质的变化。结果脊髓背角胶质细胞活化阳性细胞数疼痛组明显增加,药物干扰组明显减少;P物质主要表达于脊髓背角且疼痛模型组明显增多,药物干扰组明显减少。结论胶质细胞活化是CP/CPPS大鼠脊髓背角P物质变化的重要原因,胶质细胞活化抑制剂的应用将是治疗CP/CPPS的新亮点。 相似文献
19.
目的:探讨背根神经节(DRG)内P物质(SP)、降钙素基因相关肽(CGRP)免疫阳性神经元与阴茎包皮系带感觉信息传递之间的关系。方法:通过荧光金(FG)逆行标记对大鼠阴茎包皮系带内神经末梢的来源作追踪定位,并结合SP、CGRP免疫荧光标记法,研究大鼠DRG内FG标记阳性神经元中SP、CGRP免疫阳性神经元的形态和分布。结果:FG逆行标记结果发现,大鼠阴茎包皮系带内的神经末梢起源于第6腰髓对应的背根神经节(L6-DRG)和第1骶髓对应的背根神经节(S1-DRG)的神经元。对这些神经元分别作SP、CGRP免疫荧光标记后发现,标记细胞大小不等,分别呈深红色和深绿色,沿神经束成行排列或散在分布。FG/SP、FG/CGRP双标记阳性细胞均为中小型,其数量分别占FG逆行标记阳性细胞总数的1/3和1/2,FG/SP/CGRP三标记阳性细胞占FG逆行标记阳性细胞总数的1/5。结论:大鼠L6-DRG和S1-DRG内的SP、CGRP免疫阳性神经元可能参与阴茎包皮系带感觉信息的传递。 相似文献
20.
目的:探讨P物质抑制剂-辣椒素及bFGF抗体单独或联合使用对体外培养的人体增生性瘢痕成纤维细胞增殖的影响。方法:体外培养12例增生性瘢痕组织的成纤维细胞,分别加入不同浓度的辣椒素或/和bFGF抗体,培养24h后观察细胞形态学变化,并用MTT法检测细胞增殖抑制率。结果:所有不同浓度的辣椒素(2.5,5,20,40,60,80mg/L)均能使细胞皱缩、坏死,抑制细胞增殖,其抑制作用随剂量增大而增加。中高浓度bFGF抗体(40,80mg/L)也可促使细胞皱缩、坏死,抑制细胞增殖,其抑制作用也随剂量增大而增加。辣椒素与bFGF抗体联合应用对成纤维细胞抑制作用较单独使用效果更显著(P﹤0.05)。结论:辣椒素及bFGF抗体可抑制增生性瘢痕成纤维细胞增殖,其抑制作用随浓度增加而增加,两者联合使用有协调作用,本研究结果可能在增生性瘢痕的治疗提供新的思路和手段。 相似文献