曲马多抑制大鼠神经病理性痛和脊髓背角NR2B表达

目的:研究曲马多对神经病理性痛(neuropathic pain,NP)大鼠的镇痛作用及对脊髓背角N-甲基-D-天门冬氨酸(N-Methyl-D-Aspartate,NMDA)受体NR2B亚基表达的影响.方法:雄性wistar大鼠,随机分为3组(每组10只):假手术组(Sham operation,SO组)、NP模型组(NP组)、曲马多处理组(Tramadol组,T组).NP模型采用慢性坐骨神经压迫损伤的方法制作.各组大鼠分别于术前和术后3、7、10、14d测术侧后爪机械缩足阈值(mechanical withdrawal threshold,MWT)和热缩足潜伏期(thermal withdrawal latency,TWL).T组于术后3d开始腹腔注射曲马多注射液(20 mg/kg),术后14d取大鼠脊髓背角用免疫荧光法与RT-PCR方法检测NR2B蛋白和mRNA表达水平.结果:与SO组比较,NP组术后痛阈明显降低,NR2B表达水平明显升高(P＜ 0.05).与NP组比较,T组术后痛阈升高,NR2B表达水平明显降低(P＜0.05).T组和SO组比较,痛阈和NR2B表达水平差异无统计学意义.结论:曲马多可反转NP模型脊髓背角的NR2B表达上调并具有镇痛作用.     

外周电刺激对脊髓损伤后慢性中枢性疼痛的抑制作用

目的 探讨外周电刺激抑制脊髓损伤后中枢性疼痛的可能机制。方法 将脊髓损伤后中枢性疼痛的雄性SD大鼠24只随机分成不插入不锈钢针组（A组）、在相应穴位插入不锈钢针而不行外周电刺激（PES）组（B组）、在相应穴位插入不锈钢针行PES组（C组），每组8只，另选取正常大鼠8只作为对照组（D组）。通过机械性痛敏压力阈值（PWPT）和热痛敏潜伏期（PWL）对其伤害性刺激的痛觉过敏进行评价，同时观察其自发痛行为现象（包括自噬、搔抓等），然后，经后肢和背部标准穴位插入不锈钢针对中枢性疼痛大鼠行PES，通过免疫组化检测脊髓背角N-甲基-D-天门冬氨酸（NMDA）受体亚单位表达的变化。结果 与其他两组相比，C组大鼠中枢性疼痛得以缓解，PWPT及PWL显著增高（P〈0．01），且NR—1表达显著降低（P〈0．01），3组大鼠脊髓背角NR—1表达比正常大鼠明显增多（P〈0．01）。结论 外周电刺激对脊髓损伤后中枢性疼痛具有抑制作用。     

电针镇痛与神经病理性疼痛大鼠脊髓大麻素2受体表达

目的:观察电针对慢性坐骨神经缩窄性损伤(CCI)模型大鼠的镇痛效果及脊髓背角、背根神经节大麻素2受体(CB2)表达,探讨电针镇痛可能的机制.方法:健康SD雄性大鼠共40只,随机分为CCI假手术组(n=10);CCI对照组(n=10);CCI假电针组(n=10);CCI电针组(n=10).所有大鼠均在术前、术后第9、11、13、15、16d进行机械性痛阈测定;各组大鼠于术后第16d,采用Western blot法测定脊髓背角、背根神经节CB2受体蛋白表达.结果:CCI对照组、CCI假电针组和CCI电针组大鼠在治疗前机械性痛阈较术前明显下降,与同一时间段CCI假手术组大鼠比较差异有统计学意义(P＜0.05).治疗后6d,CCI电针组机械性痛阈较治疗前有一定改善(P＜0.05);CCI电针组与CCI假电针组和CCI对照组比较脊髓背角、背根神经节CB2的表达有下降的趋势,但差异无统计学意义(P＞0.05).结论:本研究观察到电针治疗能够在一定程度上改善CCI模型大鼠的机械性痛阈,起到一定的镇痛效果,但是本研究结果未能提示其镇痛机制有脊髓背角、背根神经节CB2的参与.     

氯胺酮对甲醛致痛诱导大鼠脊髓背角神经元兴奋性的抑制

背景：氯胺酮是否可通过影响脊髓水平的伤害性信息的传递而发挥抗伤害作用尚不清楚；一氧化氮在脊髓水平主要参与痛觉过敏的形成和发展，可诱导Fos表达，但其是否参与了氯胺酮对痛信号的转导或调控的机制不明。 目的：观察大鼠脊髓对甲醛痛刺激的反应及氯胺酮的影响。 设计：均衡随机的动物实验。 单位：徐州医学院附属医院麻醉科和江苏省麻醉学重点实验室。 材料：实验于2000-01／03在徐州医学院江苏省麻醉学重点实验室进行。取SD大鼠30只，用均衡随机方法分为6组。甲醛组6只，甲醛＋氯胺酮组6只，氯胺酮＋甲醛组6只，氯胺酮组6只。甲醛＋生理盐水组3只，生理盐水组3只，各组雌雄比例相同。 方法：④甲醛组：体积分数为0．05的甲醛200μL一侧前爪掌心皮下注射，刺激1h。②甲醛＋氯胺酮组：甲醛痛刺激10min后腹腔注射100mg／kg氯胺酮1h。③氯胺酮＋甲醛组：腹腔注射氯胺酮10min，后再行甲醛痛刺激1h。④氯胺酮组：腹腔注射同等剂量氯胺酮1h。⑤甲醛＋生理盐水组：甲醛痛刺激10min后腹腔注射等容（10mL／kg）的生理盐水1h。⑥生理盐水组：腹腔注射等容生理盐水1h。 主要观察指标：①各组大鼠行为学表现。②取脊髓切片，用c-fos基因免疫组化法和NADPH-d组化技术染色，观察大鼠脊髓背角4层（Ⅰ～Ⅱ层，Ⅲ～Ⅳ层，Ⅴ～Ⅵ层，Ⅶ～Ⅹ层）切片Fos样免疫阳性神经元（FLI）和FLI／NOS双标记神经元的数目变化。 结果：30只大鼠全部进入结果分析。①行为学变化：甲醛组及甲醛＋生理盐水组大鼠注射甲醛后，出现痛反应；注射氯胺酮的大鼠，注射后数分钟内翻正反射消失，无明显的痛行为表现，而呈持续睡眠状态。至灌注时翻正反射仍未恢复。②FLI神经元表达：甲醛组及甲醛＋生理盐水组大鼠注射侧脊髓背角出现大量FLI阳性神经元，主要分布在脊髓背角Ⅰ～Ⅱ层；氯胺酮＋甲醛组、甲醛＋氯胺酮组大鼠脊髓FLI细胞的分布与甲醛组及甲醛＋生理盐水组基本相似，但FLI阳性细胞数量显著减少（P〈0．01）；氯胺酮组和生理盐水组大鼠脊髓未见或偶见FLI阳性细胞。③FLI／NOS双标记神经元表达：氯胺酮＋甲醛组、甲醛＋氯胺酮组脊髓背角Ⅰ～Ⅱ层双标记神经元数目显著少于甲醛组及甲醛＋生理盐水组[（1&;#177;1），（1&;#177;1），（7&;#177;3），（8&;#177;3）个／切片，P〈0．01]，氯胺酮组和生理盐水组无表达。 结论：同侧相应脊髓节段的某些神经元参与了化学性致痛信息的传导和调控，氯胺酮通过抑制这些神经元的活动而产生抗伤害作用；此作用与抑制脊髓内一氧化氮合酶阳性神经元的活性有关。     

兔坐骨神经火器伤后腰段脊髓脂质过氧化反应及意义

目的：探讨脂质过氧化反应在兔坐骨神经火器伤后腰段脊髓细胞凋亡中的意义。方法：火器伤组靶点为兔右后肢外侧坐骨神经体表投影线中；切割伤组在同一致伤水平切断坐骨神经。用DNA电泳，TUNEL染色技术对腰段脊髓细胞进行凋亡定性检测，用流式细胞术进行定量检测，同时测腰段脊髓超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量，结果：火器伤组1周和2周时，腰段脊髓神经元和胶质细胞发生凋亡，切割伤组仅在4周时有少量运动神经元发生凋亡，火器伤组1d时，MDA含量显著下降（P＜0．01），3d,1周，2周时，MDA含量显著升高（P＜0．01），切割伤组MDA含量变化不明显，结论：火器伤组细胞凋亡发生时间早，数量多，脂质过氧化反应是其发生的原因之一。     

氯胺酮对神经病理性疼痛大鼠脊髓P2X_4受体mRNA表达的影响

目的:研究氯胺酮对神经病理性疼痛大鼠脊髓P2X_4受体mRNA表达的影响.方法:雄性SD大鼠45只,体重180～220g,随机分为假手术组(S组)、对照组(C组)和氯胺酮Ⅰ、Ⅱ、Ⅲ组(KⅠ、Ⅱ、Ⅲ组),每组9只.S组大鼠仅分离坐骨神经但不结扎,其余组建立坐骨神经慢性压迫性损伤(CCI)模型,K Ⅰ、Ⅱ、Ⅲ组分别于CCI后3d开始至取材点每天腹腔注射氯胺酮5mg/kg、10mg/kg、20mg/kg;S组和C组注射相同体积的生理盐水.各组大鼠分别于术前1d,术后3d、7d、14d、21d测定大鼠机械性痛觉过敏(MWT)和热痛觉过敏(TWL).各组均分别于CCI术后7d、14d、21d取3只大鼠,测定痛阈后处死,取L_(4～5)脊髓组织,用逆转录PCR(RT-PCR)方法测定P2X_4受体mRNA表达水平.结果:与术前及S组比较,C组、K Ⅰ、Ⅱ、Ⅲ组术后3d开始热痛阈及机械痛阈显著降低(P＜0.05).与C组比较,K Ⅰ、Ⅱ、Ⅲ组术后7d,14d,21d热痛阈及机械痛阈显著升高(P＜0.05).与S组比较,C组、K Ⅰ、Ⅱ、Ⅲ组大鼠脊髓P2X_4受体表达在术后7d、14d、21d均显著增加(P＜0.05);与C组大鼠比较,K Ⅰ、Ⅱ、Ⅲ组脊髓P2X_4受体表达明显减少(P＜0.05).结论:腹腔注射氯胺酮可抑制慢性神经痛大鼠痛觉过敏,该作用可能是通过作用于P2X_4受体介导的.     

慢性坐骨神经痛大鼠脊髓和海马组织脑源性神经生长因子表达的改变

目的:探讨慢性坐骨神经挤压损伤(chronicconstrictioninjujry,CCI)大鼠脊髓和海马组织中脑源性神经生长因子(brain-derivedneurotrophicfactor,BDNF)表达的改变。方法:雄性SD大鼠12只,随机分为2组,按Bennett和Xie法制作CCI模型,以von-Freyfilament和冰水测定触痛及冷水阈值,采用免疫组化法测定CCI大鼠脊髓和海马组织中BDNF表达。结果:术后14d,CCI大鼠脊髓背角(手术侧)BDNF免疫阳性表达增加153.3%,双侧海马CA3区锥体细胞BDNF表达均有增加,手术同侧增加65.7%,手术对侧增加203.8%。结论:慢性坐骨神经损伤后,脊髓和海马CA3区BDNF表达增加,提示内源性BDNF可能参与了慢性坐骨神经痛的发病过程。     

JAK/STAT通路介导脓毒症大鼠肝组织高迁移率族蛋白B1 mRNA表达的研究

目的：探讨Janusk激酶／信号转导和转录激活子（JAK／STAT）通路对盲肠结扎穿孔术（CLP）所致脓毒症大鼠肝组织高迁移率族蛋白B1（HMGB1）mRNA表达和急性肝损害的影响。方法：采用CLP模型，大鼠随机分为正常对照组、CLP脓毒症组、JAK2激酶抑制剂AG490和STAT抑制剂雷帕霉素（RPM）处理组。采用逆转录多聚酶链式反应测定肝HMGB1 mRNA，全自动生化分析仪测定肝功能指标。结果：与正常对照组相比，CLP后6－48h HMGB1 mRNA表达显著升高（P＜0．01）；血清天冬氨酸转氨酶（AST）在6－48h增高明显（P＜0．05），丙氨酸转氨酶（ALT）、AST在24h升高非常显著（P＜0．01）。与CLP组相比，AG490预处理组24h HMGB1 mRNA和ALT水平显著下降（P均＜0．01），24h和48h AST亦明显降低（P均＜0．01）；同样，RPM干预后HMGB1 mRNA表达在6h 和24h显著抑制（P＜0．05和P＜0．01），ALT、AST在24h和48h均不同程度下降（P＜0．01和P＜0．05）。结论：抑制JAK／STAT通路活化可明显下调肝组织HMGB1 mRNA表达，并有助于减轻CLP所致急性肝损伤。     

电针治疗对神经病理性疼痛中嘌呤能受体的影响及其作用机制研究

目的 观察电针对CCI大鼠脊髓背角小胶质细胞激活和P2X4受体表达的影响，并进一步探讨同时干预CCPA特异性作用受体A1受体与P2X4受体是否在电针痛觉调制中存在强化镇痛效应。 方法 选取成年清洁级健康Sprague-Dawley（SD）雄性大鼠40只，体重150~180 g。按随机数字表法分为假模组、CCI模型组、电针组、腺苷A1受体激动剂2-氯环戊腺苷(CCPA)组和电针CCPA组，每组大鼠8只。CCI模型组、电针组、CCPA组和电针CCPA组均建立大鼠CCI模型，假模组仅暴露坐骨神经。造模成功后，CCPA组和电针CCPA组均行足三里和阳陵泉两穴位注射CCPA 20 μl，0.1 mm/L；电针组和电针CCPA组（穴位注射后）则接受电针治疗；假模组和CCI模型组不做CCPA和电针干预。于造模前和造模成功20 d后，对5组大鼠进行痛阈测定，包括机械缩足反射阈值（MWT）和热缩足反射潜伏期（TWL）。于痛阈测定结束后，即刻处死大鼠，取出L4～L6脊髓段，采用双标免疫组织化学染色法分析5组大鼠每个P2X4R、OX42阳性细胞的平均荧光强度。OX42和P2X4受体的荧光密度与痛阈差值的相关性采用Spearman秩相关系数进行分析。 结果 造模成功20 d后，CCI模型组大鼠的MWT值和TWL值均显著低于假模组、电针组、CCPA组和电针CCPA组，差异均有统计学意义（P<0.01）。造模成功20 d后，CCI模型组大鼠脊髓组织中P2X4和OX42的表达显著高于假模组、CCPA组、电针组和电针CCPA组，差异均有统计学意义（P<0.01）。通过分析OX42和P2X4受体的荧光密度与痛阈差值的相关性，确定OX42和P2X4受体的荧光密度与痛阈差值呈明显的正相关，相关系数分别为0.907、0.717，差异均有统计学意义（P<0.01）。 结论 CCI后大鼠痛觉过敏与脊髓背角P2X4受体表达和小胶质细胞的活化相关，CCPA和电针治疗均可降低P2X4受体的表达，抑制小胶质细胞的活化，同时干预CCPA作用受体A1受体和P2X4受体可增强电针的镇痛效应。     

鞘内注射右美托咪定对坐骨神经慢性缩窄性损伤大鼠脊髓背角肿瘤坏死因子α蛋白表达的影响

目的探讨鞘内注射右美托咪定（ DEX）对坐骨神经慢性缩窄性损伤（ CCI）大鼠脊髓背角肿瘤坏死因子α（ TNF-α）蛋白表达的影响。方法成年Sprague-Dawley雄性大鼠44只随机分为四组（ n＝11）：假手术组（ sham组）,坐骨神经慢性缩窄性损伤组（ CCI组）,生理盐水组（ CCI＋NS组）和右美托咪定组（ CCI＋DEX组）。采用von Frey纤毛分别测定了sham组和CCI组术前及术后1、3、5、7、14 d,以及CCI＋NS组和CCI＋DEX组术后第7天鞘内给药前和给药后1、2、3 h的机械刺激抬腿反应阈值（ PWT）。 sham组和CCI组在术后第7天,CCI＋NS组和CCI＋DEX组在术后第7天鞘内给药后1 h时间点分别余5只大鼠处死取脊髓背角,采用Werstern blot法测定TNF-α蛋白表达。结果与sham组相比,CCI组PWT自术后第3天开始出现下降,并持续至第14天（ P＜0.001）;与CCI＋NS组相比,CCI＋DEX组在给药后1 h即出现明显镇痛作用,且持续至给药后2 h（P＜0.01或P＜0.001）。 Werstern blot结果显示,和sham组比较,CCI组和CCI＋NS组大鼠脊髓背角TNF-α蛋白表达上调（ P＜0.05）;与CCI＋NS组比较,CCI＋DEX组TNF-α蛋白表达下调（ P＜0.05）。结论鞘内注射右美托咪定可通过抑制CCI大鼠脊髓背角TNF-α蛋白表达减轻神经病理性疼痛。     

ON THE PHYSICOCHEMICAL REGULATION OF THE GROWTH OF TISSUES : THE EFFECTS OF THE DILUTION OF THE MEDIUM ON THE GROWTH OF THE SPLEEN.

It may be concluded that the degree of dilution of the culture medium has a marked influence on the rate of growth of splenic tissue. The maximum acceleration was obtained in a medium composed of three volumes of normal plasma and two volumes of distilled water. The growth in this hypotonic plasma was very much larger than in normal plasma. On the contrary, the growth of the spleen in hypertonic plasma was always less than in normal plasma. In other experiments, we found that in diluted plasma there was also an acceleration of the growth of the skin, the heart, and the liver of chickens. The skin of adult frogs also grew more actively in this plasma. The optimum degree of dilution varied according to the nature of the tissues and to the species of the animals. While the plasma containing two fifths distilled water produced the largest growth of splenic tissue, a slightly less diluted medium was more favorable for the liver and the heart, and generally for the skin also. The action of hypertonic plasma varied also in a large measure. While the spleen did not grow at all in the medium containing 0.0124 and 0.0144 sodium chlorid, the skin, on the other hand, could stand a high concentration of the sodium chlorid. Even its growth was activated in media containing 0.0094 and 0.0124 sodium chlorid and was greater than with normal plasma. The spleen of kittens was very easily affected by the changes of the dilution of the plasma, while the skin of the frog presented its best growth in plasma containing one half distilled water. Marked variations in the sensitiveness of tissues to hypertonic and hypotonic media will probably be observed in animals of different species. From these experiments, three conclusions can be drawn: namely, that certain laws of growth, discovered by Loeb, in lower organisms are true also for higher organisms; that normal plasma is not the optimum medium for the growth of tissue; and that each tissue has probably its optimum medium. The growth of the spleen is, without doubt, considerably modified by the variations of the dilution and perhaps of the osmotic tension of the plasma. It is possible then that the influence of osmotic tension, discovered by Loeb, in the growth of certain organisms, is a general law applicable as well to higher forms of life— frogs, cats, and chickens—as to lower organisms—tubularia and sea-urchins. In placing tubularia in different dilutions of sea-water and distilled water, Loeb found that the greatest rate of regeneration was observed when two volumes of distilled water were added to three volumes of sea-water. But fertilized eggs of sea-urchins were more sensitive to the action of hypertonic plasma, and they all died in a dilution of sea-water with two fifths distilled water. If only one fifth distilled water was added to the sea-water they developed normally. We found that the cells of certain tissues of the chicken follow a similar rule, since the maximal growth of the spleen is obtained in plasma containing two fifths distilled water, while other tissues grow better in a less hypotonic medium. Normal plasma is certainly not the ideal medium for the growth of tissues, since slight modifications of the tension, the alkalinity, or the addition of certain inorganic salts to normal plasma, increase the rate of the growth of tissues.     

THE PATHOGENESIS OF THE HEMORRHAGIC DISEASES OF THE NEW-BORN

Those conditions of the new-born characterized by a hemorrhagic tendency, icterus, and fatty changes, are probably all syndromes which may occur as the result of a number of toxic agents. All of them, however, have been produced, in these experiments, by the action of a single experimental agent. Thus, a picture indistinguishable from that called Buhl''s disease has been obtained by the use of chloroform, as have also the pictures known as Winckel''s disease, melæna neonatorum, etc. Chloroform is not held to be the only substance that has this power. It stands rather as one member of a group of agents, the effects of which in general and in individual organs are similar to those caused by lack of oxygen. The essential features of these conditions have also been produced by direct asphyxiation of the fetus. The suggestion is therefore made that underlying all these symptoms and pathological complexes, there is a deficiency of oxidation, general, local, or selective, thus bringing this group of diseases into the general category of acute yellow atrophy of the liver, eclampsia, pernicious vomiting, cyclic vomiting, phosphorus poisoning, etc. In human beings, chloroform and asphyxia must, in many instances, be the determining causes. There remain, however, other cases in which different factors are to be sought.     

THE INDUCED SUSCEPTIBILITY OF THE GUINEA-PIG TO THE TOXIC ACTION OF THE BLOOD SERUM OF THE HORSE

Following the divisions before used, the results presented in the preceding pages may be briefly stated. I. The particular method of sensitization and the place where the test injection is made have an important bearing on the results obtained by various workers. Comparing the results obtained by the various methods, we may conclude that the incubation period of the hypersensitive reaction is not sharply limited, but that there is a progressive increase in sensitiveness from the sixth day, and presumably before that, extending over a period of several weeks. It seems very probable that the degree of hypersensitiveness attained where the sensitizing dose consists of a mixture of diphtheria toxin and serum is greater than when a single dose of the same small quantity of serum is given alone. II. Our early experiments, the first in this field, are in thorough agreement with those first reported by Otto, and shortly after him by Rosenau and Anderson. III. This hypersensitive reaction is transmissible from mother to offspring. The transmission is probably not equally effective in all cases, and individual young guinea-pigs probably vary greatly in the rate with which they lose their ability to react. As a result not all of the young of a hypersensitive mother react to a subcutaneous dose of five cubic centimeters of serum given when they are four or five weeks old. The reaction in the young animals differs quite markedly from that in those actively sensitized. These differences are such as to indicate that in the mother there is a considerable localization of the reaction in tissues and organs whose destruction does not cause sudden death. This local reaction is a protective factor and is not transmitted to the same degree as the factors involved in the fatal acute reaction. IV. The hypersensitive reaction to horse serum depends on the development of a special anti-body during the incubation period, which anti-body may be passively transferred to a fresh animal. If the dose of hypersensitive serum be sufficient, and the intoxicating injection be given directly into the circulation, this passive hypersensitiveness may be enough so that the animal will die when tested. There is also in the serum of hypersensitive guinea-pigs an uneliminated horse serum element or "rest," which is distinct from this antibody, and probably without influence on the course of the acute reaction. V. The anti-body on which the hypersensitive reaction depends may be entirely neutralized by horse serum without causing symptoms. The gradual introduction of increasing doses over a total period of twenty-four hours suffices for this. The animal is then, properly speaking, neither immune nor refractory, but is essentially in the condition of a normal animal which has recently had a large dose of horse serum. This rapid neutralization is made possible by the great binding power which the subcutaneous and other relatively unimportant tissues have for the toxic element of the serum. The so-called "Phenomenon of Arthus" is probably the same reaction for the rabbit that we have here dealt with in the guinea-pig. The fact that the manifestation is more prominently a local one depends on racial differences. I have encountered cases in the guinea-pig in which the conditions in the rabbit are closely simulated.     

THE EXTENT OF THE CAPILLARY BED OF THE HEART

By means of injections made into the coronary arteries of beating hearts it has been possible to determine the number of capillaries in the normal heart muscle. This study has shown a very rich blood supply with an average of approximately one capillary for each muscle fibre in the ventricular walls and papillary muscles, and a less abundant supply in the auricular muscle and Purkinje system. The number of capillaries per sq. mm. of ventricular wall or papillary muscle is about twice that found by Krogh in skeletal muscle. Capillaries were not found constantly in the valves of hearts in which there was apparently a complete injection of the capillary bed. The method described for injecting the capillaries of the heart also provides a means of studying the blood supply to the muscle, valves and aortic wall in pathological hearts.     

THE INFLUENCE UPON THE SPLEEN AND THE THYROID OF THE COMPLETE REMOVAL OF THE EXTERNAL FUNCTION OF THE PANCREAS

The complete removal of the function of the pancreas concerned in digestion is followed by marked changes in the spleen and in the thyroid apparatus. Second, the spleen shows an extreme simple atrophy. Third, the thyroid apparatus exhibits a constant change shown by the macroscopic transparency of the gland, by the microscopic increase in the amount of colloid, by the chemical increase of the iodine content of the gland, and by the functional test of the delayed appearance of tetany after the complete removal of the thyroid apparatus.     

学生健康体检结果分析

在校学生进行健康体检,对常见病患病率进行统计分析,提议在体检 中应加入血液流变学指标。