The hypotensive effect of BMY 7378 is antagonized by a silent 5-HT(1A) receptor antagonist: comparison with 8-hydroxy-dipropylamino tetralin

BACKGROUND: Stimulation of central 5-HT(1A) receptors produces bradycardia and diminishes blood pressure in conscious or anesthetized rats. Our objective was to investigate the effects on blood pressure and heart rate of the partial 5-HT(1A) receptor agonist and selective alpha1D-adrenoceptor antagonist BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl] ethyl]-8-azaspiro [4.5] decane-7,9 dione hydrochloride) compared to the full 5-HT(1A) receptor agonist 8-OH-DPAT (8-hydroxy-dipropylamino tetralin) in adult anesthetized rats. METHODS: Male Wistar rats of 6 months of age were exposed intravenously (i.v.) to increasing doses of BMY 7378 or 8-OH-DPAT in the absence and presence of WAY 100635. Blood pressure and heart rate were continuously recorded. RESULTS: BMY 7378 induced a decrease in blood pressure with no apparent change in heart rate compared to basal values, while 8-OH-DPAT decreased both hemodynamic parameters. BMY 7378 hypotensive effect was antagonized by the selective, silent 5-HT(1A) receptor antagonist WAY 100635 (N-[2-[4-(2-methoxyphenyl)-1-piperazinyl] ethyl]-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride). However, a remnant yet significant hypotensive effect was not blocked by the antagonist. In contrast, 8-OH-DPAT actions were completely blocked by WAY 100635. CONCLUSIONS: Data suggest that BMY 7378 cardiovascular effects are related to activation, as a full agonist, of central 5-HT(1A) receptors in adult rats; however, participation of other systems such as vascular alpha1-adrenoceptors in cardiovascular function is suggested.     

Vascular alpha 1D-adrenoceptor function is maintained during congestive heart failure after myocardial infarction in the rat

BACKGROUND: During congestive heart failure, desensitization of beta-adrenoceptors is related to a lower adrenergic responsiveness in the heart; little is known about alpha 1-adrenoceptors in the vasculature under this condition. We evaluated alpha 1D-adrenoceptor response in aorta and carotid arteries in a model of congestive heart failure (CHF) post-myocardial infarction. METHODS: Noradrenaline-elicited contraction was determined in endothelium-denuded arterial rings from young (10-week-old) Wistar rats in the absence and presence of the alpha 1D-adrenoceptor antagonist BMY 7378 (8-(2-(4-(2-methoxyphenyl)-1-piperazinyl) ethyl)-8-azaspiro(4,5)decane-7,9-dione dihydrochloride) in sham-operated rats and in rats that developed CHF 4 weeks or 7 months after myocardial infarction. RESULTS: In the thoracic aorta, BMY 7378 displaced noradrenaline effect to the right with pA2 values of: sham, 8.58 +/- 0.12; CHF, 8.36 +/- 0.13, and sham, 8.56 +/- 0.10; CHF, 7.99 +/- 0.13 at 4 weeks and 7 months after myocardial infarction, respectively. While in carotid arteries, the pA2 values were: sham, 8.43 +/- 0.19; CHF, 8.81 +/- 0.19, and sham, 8.35 +/- 0.18; CHF, 8.29 +/- 0.08 at 4 weeks and 7 months after myocardial infarction, respectively. When adult (7-month-old) rats were subjected to myocardial infarction, CHF was not installed and pA2 values were similar and high in both sham and infarcted rats. CONCLUSIONS: These results indicate that alpha 1D-adrenoceptors remained as the main receptors involved in contraction in aorta and carotid arteries, irrespective of CHF duration.     

8-OH-DPAT对新生鼠离体延髓脑片呼吸节律性放电的影响

目的 探讨激活5-HT1A受体对延髓基本节律性呼吸放电的影响.方法 制备20只新生SD大鼠(0～3 d)离体延髓脑片标本,以改良的Kreb's液恒温灌流,稳定记录到与之相连的舌下神经的呼吸节律性放电活动(RRDA)后,随机分成Ⅰ～Ⅳ组(每组n=5).Ⅰ～Ⅳ组给予5-HT1A受体的特异性激动剂( /-)-8-hydroxy-2-(di-N-propylamino)tetralin hydrobromide(8-OH-DPAT),浓度分别为1、5、10、20 μmol/L持续灌流10 min,观察给药后1、3、5 min时舌下神经的呼吸节律性放电活动的变化.结果 给药前后不同时间点之间呼吸周期(RC)有显著性差异(F=181.219,P＜0.001),各浓度在给药前RC最小,给药后逐渐延长,5 min时达到最大.各浓度之间有显著性差异(P＜0.001),给药后各时间点1 μmol/L的RC最小,给药浓度增大,RC延长,20 μmol/L时RC最大.给药前后和不同浓度之间存在交互效应(P＜0.001).给药前后不同时间点之间积分幅度(IA)有显著性差异(P＜0.001),在10 μmol/L和20μmol/L浓度组中给药前后不同时间点之间有显著性差异(P=0.017和0.001).各浓度之间有显著性差异(P＜0.001),给药后各时间点1μmol/L的IA最大,给药浓度增大IA减小,20μmol/L的IA最小.给药前后和不同浓度之间存在交互效应(P=0.002).结论 (1)8-OH-DPAT长效抑制吸气活动,对新生大鼠离体延髓脑片标本呼吸周期具有剂量依赖性延长作用,对频率和积分幅度具有剂量依赖性抑制作用.(2)5-HT1A受体参与了哺乳动物基本呼吸节律的产生和调节.     

脑室内注射5,7-双羟色胺对内侧前额叶皮层锥体神经元5-HT1A受体敏感性的影响

目的：探讨脑室内注射5,7-双羟色胺（5,7-DHT）对内侧前额叶皮层（mPFC）锥体神经元5-羟色胺-1A(5-HT1A)受体敏感性的影响,阐明5-HT1A受体对锥体神经元电活动的作用。方法：36只雄性SD大鼠随机分为假手术组（n=21）和5,7-DHT损毁组（n=15）。损毁组大鼠脑室内注射5,7-DHT,假手术组大鼠脑室内注射同等剂量生理盐水,2组大鼠静脉注射不同剂量(0.5～128.0 μg•kg^-1)5-HT1A受体激动剂8-OH-DPAT,采用体细胞外电生理学方法观察mPFC中锥体神经元放电频率的变化,并静脉注射5-HT1A受体拮抗剂WAY100635,观察损毁组大鼠对5,7-DHT激动剂和拮抗剂的敏感性,并与假手术组进行比较。结果：在假手术组中,不同剂量（0.5～128.0 μg•kg^-1） 8-OH-DPAT对大鼠锥体神经元的放电频率均产生兴奋-抑制式的影响,这些神经元在低剂量（0.5～32.0 μg•kg^-1）时被兴奋,放电频率增加(P<0.05);而在高剂量（128.0 μg•kg^-1）时则被抑制,放电频率减少。在损毁组中,不同剂量（0.5～128.0 μg•kg^-1）8-OH-DPAT剂量依赖性地抑制大鼠锥体神经元的电活动（df= 5,F=3.44,P =0.003）,即放电频率减少,未见兴奋-抑制效应;WAY10035可以反转8-OH-DPAT的抑制作用。结论：脑室内注射5,7-DHT可使大鼠mPFC锥体神经元5-HT1A受体敏感性降低。     

5-羟色胺及其突触后1A受体对慢性应激大鼠情绪和认知的影响

目的:研究5-羟色胺(5-HT)及其突触后1A受体(5-HT1A)在应激适应中的作用.方法:使用对氯苯丙胺(p-PCA)将大鼠体内5-HT耗竭,并使用5-HT1A受体激动剂8-OH-DPAT及拮抗荆WAY100635,研究慢性应激、5-HT及其突触后5-HT1A受体等对大鼠在高架十字迷宫、强迫游泳和水迷宫测试中行为的影响.结果:应激后5-HT耗竭大鼠比正常大鼠在高架十字迷宫实验中开臂停留时间较少,闭臂停留时间较多;强迫游泳实验中不动时间较长;在水迷宫测试的第3,4天,逃离潜伏期明显增加,测试时在目标象限停留时间和穿越原平台位置次数明显减少.8-OH-DPAT能显著减少5-HT耗竭大鼠及5-HT耗竭应激大鼠焦虑和抑郁水平,上述作用则能被WAY100635阻断.在水迷宫实验中,8-OH-DPAT及WAY100635对大鼠找到平台的平均潜伏期、在目标象限的时间和穿越平台的次数无明显影响.结论:5-HT耗竭大鼠应激时更容易产生抑郁和焦虑症状,并易导致学习、记忆等认知功能受损,时应激适应能力下降.突触后5-HT1A的激活能够缓解5-HT耗竭及5-HT耗竭应激大鼠的焦虑和抑郁症状,促进对慢性应激的适应,但其对大鼠的学习记忆等认知功能无明显影响.     

蛋白酶抑制剂对内毒素致大鼠急性肺损伤的保护作用

目的:静脉应用蛋白酶抑制剂以了解其对内毒素所致的大鼠肺损伤的保护作用及其机制.方法:雄性Wistar大鼠32只,体重(250～270 g),分为对照组(C,n=8)、内毒素组(A,n=8)、大剂量治疗组(U,n=8)及小剂量治疗组(V,n=8),除对照组外,其他组均给予内毒素(5 mg/kg),治疗组同时给予内毒素和乌司他丁注射(U组100 000 u/kg,V组50 000 u/kg).2 h后测定血清内皮素,进行动脉血气分析,取肺组织观察大体标本形态和光镜下的组织病理形态,测定肺组织血管通透性变化、湿/干质量比值、髓过氧化物酶活性、脂质过氧化产物[丙二醛(malonaldehyde,MDA)和共轭二烯(conjugated-diene,C-diene)].结果:光镜下可见对照组肺组织学正常,内毒素组肺间质弥漫性出血,肺泡腔内可见大量粒细胞聚集、浸润,并可见弥漫性肺泡间隔增厚,而乌司他丁治疗组上述病理表现明显减轻.肺组织湿/干质量比值和每克肺组织伊文思蓝含量在内毒素组分别为(5.41±0.06)和(27.64±2.48)μg,对照组分别为(4.95±0.08)和(12.99±2.83)μg,组间比较差异有统计学意义;U组为(5.0±0.05)和(19.47±2.09)μg;V组为(4.98±0.06)和(21.44±3.12)μg,明显低于内毒素组,U组和V组间差异无统计学意义.血清内皮素及髓过氧化物水平内毒素组分别为(948.23±103.45)u/g和(152.90±8.41)u/g,高于对照组的(729.38±88.64)u/g和(54.62±15.49)u/g,U组为(633.27±93.27)u/g和(119.40±11.32)u/g,V组为(671.87±105.45)u/g和(129.55±9.57)u/g,则低于内毒素组,U组和V组间差异无统计学意义.肺组织脂质过氧化产物水平内毒素组[(MDA(73.95±4.62)nmol/g;C-diene(10.96±0.81)nmol/g]明显高于对照组[MDA(39.65±6.21)nmol/g;C-diene(3.34±0.51)nmol/g],治疗组[U组:MDA(51.26±5.56)nmol/g,C-diene(7.59±0.84)nmol/g;V组:MDA(59.87±4.62)nmol/g,C-diene(8.79±0.45)nmol/g]则较内毒素组明显降低,MDA水平U组低于V组.结论:乌司他丁明显降低肺组织的炎症反应,减轻肺组织的损害,对内毒素所致大鼠肺损伤具有一定的保护作用.     

PSD-95信号通路介导5-HT1A受体激动剂改善大鼠病理性攻击行为的调控机制

目的 探索突触后致密物-95(postsynaptic density-95,PSD-95)信号通路是否参与并介导5-HT1A受体激动剂对大鼠病理性攻击行为的改善作用及调控机制.方法 将成功构建的24只病理性攻击大鼠按照抽签法分为4组,分别为8-OH-DPAT组、8-OH-DPAT+ZL006组、ZL006组、NaCl组,5-HT1A受体激动剂(8-OH-DPAT)以1 mg/kg每日腹腔注射并持续2周、PSD-5阻断剂(ZL006)以1mg/kg每隔3天腹腔注射并持续2周.分别在给药前、给药1周后及给药2周后用居住-入侵实验测试大鼠病理性攻击行为变化,且每次居住-入侵实验前取大鼠眼眶后静脉血.取前额叶皮层、大鼠海马及下丘脑组织,用Western blot检测各脑区五羟色胺1A受体(serotonin 1A receptor5-HT1AR)、PSD-95及糖皮质激素受体(glucocorticoid receptor,GR)的表达,并采用ELISA试剂盒检测血清糖皮质激素含量.结果 8-OH-DPAT组大鼠攻击总数、攻击持续时间及攻击要害部位比在给药1周及2周后均有明显下降(P＜0.05);8-OH-DPAT+ ZL006组大鼠仅在给药1周后有降低(P＜0.05).Western blot检测结果显示8-OH-DPAT组、8-OH-DPAT+ ZL006组前额叶皮层及海马5-HT1A受体表达均高于其余两组(P＜0.05);8-OH-DPAT组大鼠前额叶皮层及海马PSD-95表达高于其余3组(P＜0.05);且该组海马GR表达低于其余3组(P＜0.05);各组大鼠下丘脑5-HT1AR、PSD-95表达差异无统计学意义(P＞0.05).ELISA结果显示:给药2周后8-OH-DPAT组血清糖皮质激素浓度有明显上升(P＜0.05),而其余3组在干预前后血清糖皮质激素无明显变化(P＞0.05).结论 PSD-95信号通路参与并介导了5-HT1A受体激动剂(8-OH-DPAT)对大鼠病理性攻击行为的改善作用,可能是通过对血清糖皮质激素的调控而发挥作用.     

慢性应激抑郁模型大鼠海马5-HT1A受体的变化

目的 :探讨慢性不可预见性应激抑郁模型大鼠海马 5 -HT1A受体 (5 -HT1AR)的变化以及三环类抗抑郁剂 (TCAs)阿米替林和 5 -羟色胺再摄取抑制剂 (SSRI)氟西汀对其影响。方法 :将 2 4只SD雄性大鼠随机均分为 4组 ,即对照组、抑郁组、阿米替林治疗组、氟西汀治疗组。应用 [3H]8-OH -DPAT作为放射性配基 ,使用放射性配体受体结合法测定大鼠海马 5 -HT1AR的特异性结合。结果 :与对照组相比 ,抑郁组大鼠海马 [3H ]8-OH -DPAT特异性结合下降 2 8.10 % (P <0 .0 5 )。阿米替林治疗 2 1d ,抑郁大鼠海马的 [3H]8-OH -DPAT特异性结合明显提高至 (2 6 .6 3±5 .5 0 )fmol/mgprotein ,与抑郁组 (18.78± 5 .6 2 )fmol/mgprotein比较有显著性差异 (P <0 .0 5 ) ,与对照组 (2 6 .12± 5 .5 2 )fmol/mgprotein比较无显著性差异 (P >0 .0 5 ) ;氟西汀治疗 2 1d ,抑郁大鼠海马的 [3H]8-OH -DPAT特异性结合无显著变化 (P >0 .0 5 )。结论 :①抑郁大鼠海马 5 -HT1AR特异性结合下降可能与抑郁症病因相关。②海马 5 -HT1AR可能是阿米替林发挥抗抑郁作用的环节。③氟西汀可能不通过影响海马突触后膜的 5 -HT1AR发挥抗抑郁作用     

Serotonin (5-HT1c) receptors in pig choroid plexus.

It is very important to find suitable reaction conditions to attain a high specific binding (specific/total binding) in the receptor binding study. Membrane homogenates of pig choroid plexus are known to have exclusively serotonin (5-hydroxytryptamine, 5-HT) receptor of the subtype 5-HT1c. In this study, we used the membrane preparation of pig choroid plexus tissue and the specific binding of [3H]5-HT was 72-84% to serotonin receptor subtype 5-HT1c, as defined by the inhibition of 1 uM 5-HT, when a radioligand concentration of 0.5 nM of [3H]5-HT was used in the assay. Analysis of the properties of specific [3H]5-HT binding in pig choroid plexus tissue membrane preparation revealed linear Scatchard plots. In Tris-HCl buffer without CaCl2, pargyline or ascorbic acid, high average of affinity dissociation constant (Kd) of 1.3 +/- 0.2 nM (SEM, n = 4) and also a high average of receptor density (Bmax) of 284 +/- 12 fmol/mg of protein were found. Pig choroid plexus proves to be a good material for 5-HT1c receptor binding study.     

ROS-mediated ERK activation in delayed protection from anoxic preconditioning in neonatal rat cardiomyocytes

Background The activation of extracellular signal-regulated kinase1/2 (ERK1/2) has been shown to be important signaling pathway in the ischemic preconditioning (IPC) response. Recently, some studies suggest a key role for the mitochondrial ATP-sensitive potassium channel (mKATP) as both a trigger and an end effector of acute and delayed protection of IPC. Hence, this study was undertaken to elucidate the relationship between mKATP and ERK1/2 in the delayed protection mechanism of anoxic preconditioning (APC). Methods An APC model was established using cultured neonatal rat cardiomyocytes. Pharmacological agents ［diazoxide, 5-hydroxydecanoate (5-HD), 2-mercaptopropionylglycine (MPG), and PD98059］ were used to modulate mKATP and ERK1/2 activation. Cellular injury was evaluated by measuring cellular superoxide dismutase (SOD) activity, cell viability, and lactate dehydrogenase (LDH) release. The generation of cellular reactive oxygen species (ROS) and the activation of ERK1/2 were determined at different time points starting from the beginning of preconditioning with anoxia or diazoxide (an mKATP opener). Results Cell viability and SOD activity in the APC ［(81.9±11.4)%, （13.6 ± 3.7） U/L］ and diazoxide ［(79.2±12.4)%, （16.5±4.6） U/L］ groups were significantly higher than in the anoxia/reoxygenation (A/R) ［(42.2±7.3)%, （8.8±2.8） U/L］ group (all P&lt;0.01). LDH activity in the APC group ［(101.9±18.9) U/L］ and diazoxide group ［(97.5±17.7) U/L］ was significantly lower than in the A/R group ［(250.5±43.6) U/L］ (all P&lt;0.01). Both APC and diazoxide simultaneously facilitated intracellular ROS generation and rapid ERK1/2 activation. But the effects of APC and diazoxide were remarkedly attenuated by 5-HP (an mKATP blocker) and by MPG (a free radical scavenger). In addition, the ERK1/2 inhibitor PD98059 also abolished the cellular protective effects induced by diazoxide. Conclusion mKATP may mediate ERK1/2 activation during anoxia preconditioning by generating ROS, which then triggers the delayed protection of APC in rat cardiomyocytes.     

5-HT1A受体激动剂（8-OH-DPAT）对大鼠弥漫性轴索损伤神经保护作用的实验研究

目的探讨8-OH-DPAT[8-hydroxy-2-（di-n-propylamino）tetralin]对大鼠弥漫性轴索损伤（DAI）的降低脑温及神经保护作用。方法选用SD大鼠30只,建立大鼠DAI模型。模型制成后,将大鼠随机分为三组,A组（对照组）：10只,伤后15 min腹腔给予等量生理盐水;B组（恒定体温组）：10只,维持体温恒定,伤后15 min腹腔给予8-OH-DPAT;C组（实验组）：10只,伤后15min腹腔给予8-OH-DPAT。记录相应时点各组大鼠脑红蛋白（NGB）、热休克蛋白70（HSP70）表达量变化及脑温度值。结果与A组比较C组于给药后15 min即可引起脑温下降,至90 min达到高峰,3 h 25 min脑温恢复至A组水平。相应时点B、C组与A组比较NGB、HSP70的表达均有不同程度增高。结论 8-OH-DPAT具有降低DAI大鼠脑温的效果,伤后早期增强NGB及HSP70的表达起到神经保护的作用,且8-OH-DPAT降低脑温作用和神经保护作用是相辅相成的。     

内源性一氧化碳在糖尿病大鼠股动脉舒张反应障碍中的作用

目的:探讨一氧化碳(carbon monoxide,CO)对糖尿病(diabetes mellitus,DM)大鼠动脉血压和股动脉血管反应性的影响.方法:监测大鼠尾动脉血压,测定股动脉环对10-8～10-4mol/L乙酰胆碱(acetylcholine,ACh)累计舒张反应,检测血液CO含量.结果:大鼠复制DM模型4周后体重降低[(249.38±7.58)g],血糖和血压升高分别为[(20.28±0.35)mmol/L,(118.75±8.33)mm Hg,l mm Hg=0.133 kPa],较对照组饲养4周后[(345.83±12.14)g,(5.56±0.19)mmol/L和(108.43±4.18)mm Hg]差异均有统计学意义(P＜0.05);DM 8周和12周体重进一步降低,血糖无明显改变,动脉血压进一步上升分别为[(132.43±10.98)mm Hg和(139.0±10.41)mm Hg],较对照组差异有统计学意义(P＜0.01);DM大鼠4周血液中COHb含量较对照组明显降低[(1.50%±0.21%)vs(2.50%±0.61%),P＜0.05],8～12周时恢复至对照组水平;DM大鼠4～12周股动脉对ACh的累积舒张反应均明显降低,分别为(63.46%±2.48%,37.7%±5.65%,52.41%±2.31%),较对照组(96.81%±3.15%)差异有统计学意义(P＜0.01);应用正铁血红素后大鼠体重,血糖和血压无明显改善,可显著提高DM大鼠血液COHb水平(3.20%±0.73%,P＜0.01),并可明显改善血管舒张反应障碍(69.76%±7.60%,P＜0.01);而给予锌原卟啉后检测到体重降低[(218.33±9.28)g],血糖和血压升高[(24.2±2.28)mmol/L,(130.84±8.56)mm Hg,P＜0.05],血液COHb含量进一步降低(0.93%±0.35%,P＞0.05),并有加重动脉舒张反应障碍的趋势(27.73%±4.74%,P＜0.01).结论:DM大鼠早期内源性CO合成减少与股动脉舒张反应障碍密切相关,是引起DM高血压的重要机制之一.     

5-HT1A受体激动剂对青春期大鼠病理性攻击行为和前额叶皮质、海马内脑源性及胶质细胞源性神经营养因子的影响

目的 探索5-羟色胺1A(5-HT1A)受体激动剂8-OH-DPAT对青春期大鼠病理性攻击行为及对前额叶皮质、海马内脑源性神经营养因子(BDNF)和胶质细胞源性神经营养因子(GDNF)的影响.方法 出生后21 d的雄性SD大鼠42只随机分为6组(n=7):模型组、正常组、模型+药物组、模型+生理盐水(NS)组、正常+药物组、正常+NS组.模型组、模型+药物组及模型+NS组采用早年慢性应激建立病理性攻击模型,余3组正常饲养.建模成功后对模型+药物组、正常+药物组及模型+ NS组、正常+NS组分别行2周的8-OH-DPAT(0.5mg/kg)或生理盐水(2 mL/只)腹腔注射.用居住-入侵实验检测大鼠攻击行为,蛋白质印迹分析检测大鼠脑前额叶皮质及海马内BDNF、GDNF蛋白表达水平.结果 与正常组比较,模型组攻击潜伏期缩短(P＜0.01)、攻击持续时间及攻击总数增加(P＜0.01).模型+药物组攻击潜伏期较模型+NS组延长(P＜0.05);模型+药物组攻击持续时间较正常+药物组增加(P＜0.05);药物干预后攻击总数组间比较差异无统计学意义(P＞0.05).模型组前额叶皮质、海马内BDNF及GDNF表达水平均低于正常组(P＜0.01),模型+NS组较正常+NS组降低(P＜0.05,P＜0.01),模型+药物组较模型+NS组升高(P＜0.05,P＜0.01).结论 前额叶皮质及海马内BDNF、GDNF可能与早年慢性应激所致青春期大鼠病理性攻击行为的发生有关.5-HT1A受体激动剂可上调前额叶皮质及海马内BDNF、GDNF的蛋白表达,并在一定程度上减轻早年慢性应激所致青春期大鼠病理性攻击行为.     

不同时间变应原暴露对大鼠哮喘模型的影响

目的:研究幼年大鼠不同时间接触卵蛋白(ovalbumin, OVA)对成年后气道哮喘炎症的影响及机制.方法:新生SD(Sprague Dawley)大鼠随机分为哮喘组,出生后第3天、第7天、第14天变应原接触组,以及正常对照组.各变应原接触组分别于出生后第3天、第7天和第14天给予皮下注射OVA 1mg(含氢氧化铝凝胶5mg).大鼠饲养至6周龄后,除正常对照组外其他各组均经OVA致敏并激发为哮喘模型.观察大鼠肺组织病理改变,计数每个细支气管上皮中黏液细胞数量.检测脾及胸腺中CIM+ CD25+ T细胞比例和叉头框P3(forkhead box P3,Foxp3)转录因子mRNA表达水平.结果:出生后第3天组(2.29±0.49)、出生后第7天组(1.25 4±0.46)与哮喘组相比(3.50±0.76)黏液细胞数量减少(P<0.01),气道炎症明显减轻;而出生后第14天组黏液细胞数未见减少[(3.00±1.16) vs (3.50±0.76),P>0.05].出生后第3天组、第7天组脾中CD4+ CD25+ T细胞比例[(13.68±3.54)% vs (7.33±3.39)%,P<0.01;(16.65±4.91)% vs (7.33±3.39)%,P<0.01]和Foxp3 mRNA水平[(18.46±5.01)vs(5.49±1.99),P<0.01;(26.37±4.68) vs (5.49±1.99),P<0.01]与正常组比较均明显升高,且出生后第7天组胸腺中Foxp3 mRNA表达亦增高[(18.73±3.66)vs(11.13±1.75),P<0.01];但出生后第14天组脾CIM+ CD25+ T细胞比例及Foxp3 mRNA表达与正常组比较差异均无统计学意义[(11.04±2.88)% vs (7.33±3.39)%,P>0.05;(8.71±2.19) vs (5.49±1.99),P>0.05].结论:早期接触变应原对大鼠哮喘气道炎症的抑制作用存在"时间窗"现象,其发生机制可能与诱导产生调节性T细胞有关.     

长期雌激素替代治疗对血压及心肌IR和IRS-1表达的影响

目的：研究长期雌激素替代治疗对血压及心肌组织胰岛素受体（IR）和胰岛素受体底物-1（IRS-1）表达水平的影响。方法：将50只雌性SD大鼠随机分成3组，构建假手术、去势（去卵巢）和雌激素替代3组动物模型。手术前后,用尾套法测定大鼠的尾动脉收缩压，RT-PCR方法检测大鼠心肌IR和IRS-1的表达。结果：去势组血压［（118.75±2.77） mmHg］明显高于假手术组 ［（103.86±1.84）mmHg，P＜0.05］和替代组［（107.83±3.24）mmHg，P＜0.05］ 。去势组大鼠心肌IRS-1的相对表达量（1.2588±0.1045）显著低于假手术组（2.2089±0.0988, P＜0.05）和替代组(1.9100±0.1230，P＜0.05）。然而，替代组与假手术组间血压和IRS-1的表达无明显差异（P＞0.05）。假手术、去卵巢和替代组间心肌IR的表达差异无统计学意义（P＞0.05）。结论：长期雌激素替代治疗可降低血压、增加心肌细胞IRS-1的表达，从而一定程度上保护心血管。但血清雌激素水平对心肌细胞IR的表达影响不明显。     

新型气体信号分子二氧化硫对自发性高血压大鼠主动脉平滑肌细胞增殖和凋亡的影响

OBJECTIVE: To explore the effects of sulfur dioxide (SO2) on the proliferation and apoptosis of aorta smooth muscle cells in hypertension rats and possible mechanism thereof. METHODS: Sixteen 4-week-old male spontaneously hypertensive rats (SHRs) were randomly divided into 2 equal groups: control and Na2SO3/NaHSO3 (a SO2 donor)-treated group. Eight 4-week-old male WKY (Wistar Kyoto) rats were assigned for normal control group. Five weeks later, the pressure was measured. The rat aortas were dyed with Hart's method. The morphometric parameters were calculated by Leica workstation. The plasma level of SO2 was determined by HPLC method. VSMC apoptosis was measured by TUNEL technique. The expression levels of proliferating cell nuclear antigen (PCNA), Bcl-2, Fas and caspase-3 were detected by immunohistochemical assay. RESULTS: (1) Compared with those of the WKY rats, the blood pressure, ratio of media to lumen radius, and proliferation index (PI) of the SHRs were increased [(172 +/- 10) mm Hg vs (112 +/- 9) mm Hg, 0.073 +/- 0.004 vs 0.057 +/- 0.004, 0.32 +/- 0.06 vs 0.05 +/- 0.03, respectively], but the plasma level of SO2 and the apoptosis index (AI) were decreased in the SHRs [(6.4 +/- 1.5) micromol/L vs (11.3 +/- 1.0) micromol/L, 0.16 +/- 0.07 vs 0.30 +/- 0.19, respectively]. The expression of Bcl-2 was increased (0.209 +/- 0.007 vs 0.202 +/- 0.006), and the expression levels of Fas and caspase-3 of SHRs were both lower than those of the WKY rats (0.205 +/- 0.006 vs 0.211 +/- 0.005, 0.229 +/- 0.005 vs 0.244 +/- 0.010, respectively). (2) Compared with the SHR control group, the systolic blood and the ratio of media to lumen radius were decreased [(128 +/- 7) mm Hg, 0.066 +/- 0.002, respectively], but the plasma level of SO2 was increased [(8.3 +/- 1) micromol/L] for the SHR + Na2SO3/NaHSO3 group. PI was lower (0.14 +/- 0.03) and AI was higher (0.40 +/- 0.11) in SHR + Na2SO3/NaHSO3 group than those in SHR control group. The expression of Bcl-2 of VSMCs was down-regulated (0.199 +/- 0.006), but the levels of Fas and caspase-3 were up-regulated (0.218 +/- 0.003 and 0.251 +/- 0.011 respectively) in the SHR + Na2SO3/NaHSO3 group. CONCLUSION: SO2 may attenuate the structural remodeling through reducing the proliferation and enhancing the apoptosis of smooth muscle cells in SHRs. SO2 may modulate the process of apoptosis possibly through the downward regulation of the level of Bcl-2 and enhance the expression of Fas and caspase-3.     

结缔组织生长因子在肾切除大鼠肾脏中的表达和氟伐他汀的调节作用

目的　观察结缔组织生长因子 (CTGF)mRNA在 5 / 6肾切除大鼠肾皮质的表达特点和羟甲基戊二酰辅酶A(HMG CoA)还原酶抑制剂氟伐他汀的调节作用。方法　将 2 4只 5 / 6肾切除大鼠随机分为未治疗的 5 / 6肾切除组 (模型组 ,12只 )和氟伐他汀治疗的 5 / 6肾切除组 (治疗组 ,12只 ) ,另设6只假手术大鼠作为对照。氟伐他汀治疗 (7mg·kg-1·d-1) 13周后 ,检测尿蛋白排泄、血清尿素氮和肌酐含量 ,用RT PCR法检测肾皮质CTGFmRNA表达 ,免疫组织化学检测肾小球转化生长因子 β1(TGF β1)、IV型胶原和纤连蛋白的表达水平 ,并评价肾脏病变和肾小球硬化指数 (GSI)。 结果　实验终止时 ,模型组尿蛋白排泄 (30 5 4mg/ 2 4h)显著高于假手术组 (5 6mg/ 2 4h ,P <0 0 1) ,氟伐他汀治疗的大鼠尿蛋白排泄 (2 30 9mg/ 2 4h)明显低于模型组 (P <0 0 5 )。与假手术组相比 ,模型组血清尿素氮(P <0 0 1)和肌酐 (P <0 0 5 )水平均明显增高 ,氟伐他汀治疗使血清尿素氮和肌酐的含量明显降低。模型组GSI为 4 1 8± 11 5 ,明显高于假手术组 (2 2± 1 3,P <0 0 1) ,治疗组GSI(2 3 4± 6 1)明显低于模型组 (P <0 0 5 )。肾皮质CTGFmRNA表达水平约为假手术组的 3倍 (P <0 0 1) ,而在治疗组其表达水平减少 5 5 4 %。肾小球TGF     

生脉注射液对创伤失血性休克大鼠免疫功能的影响

目的探讨生脉注射液对创伤失血性休克大鼠T淋巴细胞及其亚群的影响,为揭示生脉注射液调理创伤后免疫功能紊乱机制提供依据。方法制作创伤失血性休克大鼠模型。将30只SD大鼠随机分为3组,分别为正常对照组（A组）、创伤失血性休克组（B组）、生脉注射液治疗组（C组）,每组各10只。3组大鼠分别于实验开始后第3天处死。全自动血液生化仪检测大鼠血常规,流式细胞仪检测T淋巴细胞及其亚群（CD3^＋、CD4^＋、CD8^＋）含量。结果大鼠创伤失血性休克后,机体出现过度的炎症反应和免疫功能低下状态,B组与A组比较,白细胞含量显著升高[（8.890±0.387）×10^9/L vs（4.230±0.856）×10^9/L,P=0],中性粒细胞比例显著升高[（26.15±2.97）%vs（16.00±4.53）%,P=0],淋巴细胞比例显著下降[（68.57±5.23）%vs（76.617±4.9）%,P=0.001]。应用生脉注射液治疗后,C组与B组比较,白细胞明显下降[（6.29±0.758）×10^9/L vs（8.89±0.387）×109/L,P=0],中性粒细胞比例显著下降[（20.29±3.09）%vs（26.15±2.97）%,P=0.001],同时,淋巴细胞比例显著上升[（74.85±4.12）%vs（68.57±5.23）%,P=0.007]。创伤失血性休克后,B组与A组相比,大鼠CD3^＋、CD4^＋T淋巴细胞数量显著降低[CD3＋：（31.17±4.00）vs（41.97±2.50）,P=0;CD4^＋：（10.49±1.42）vs（15.51±3.48）,P=0.003],CD4^＋/CD8^＋比值降低[（0.97±0.09）vs（1.19±0.07）,P=0],CD8＋含量变化差异无统计学意义[（17.75±5.94）vs（17.34±3.77）,P=0.997]。大鼠处于免疫功能抑制状态,在生脉注射液治疗后,C组与B组比较,CD3^＋、CD4^＋T细胞数量显著升高[CD3^＋：（36.64±5.73）vs（31.17±4.00）,P=0.001;CD4^＋：（10.49±1.42）vs（13.94±2.02）,P=0.008],CD4^＋/CD8^＋比值有所升高[（1.12±0.03）vs（0.97±0.09）,P=0.001]。结论创伤失血性休克大鼠出现炎症反应和T淋巴细胞免疫功能下降,应用生脉注射液能明显提高创伤失血性休克大鼠T淋巴细胞的免疫功能,降低炎症反应。     

泼尼松对IL-8在COPD大鼠肺组织表达的影响

目的 研究IL-8在慢性阻塞性肺病(COPD)大鼠肺组织中的表达及泼尼松对其表达的影响.方法 Wistar大鼠24只随机分为:正常对照组(A组)、单纯熏烟组(B组)和熏烟 泼尼松组(C组),每组各8只.单纯熏香烟法建立COPD模型,C组于熏香烟前予泼尼松5 mg/kg隔日灌胃.模型建立后,行支气管肺泡灌洗,测定支气管肺泡灌洗液(BALF)中细胞数,酶联免疫吸附法(ELISA)测定BALF上清液和血清中的IL-8和TNF-α浓度,并对肺组织切片行苏木精-伊红(HE)染色观察形态学改变,采用图像分析系统定量测定肺平均内衬间隔(MLI)、平均肺泡数(MAN)和肺泡腔面积与总面积比(PAA).结果 B组MLI、PAA比A组增高,而MAN低于A组,C组与B组相比MLI、PAA降低,MAN升高,差异均有统计学意义(P＜0.01).与A组比较,B组BALF中IL-8、TNF-α、白细胞总数、中性粒细胞绝对计数和中性粒细胞百分比均增高(P＜0.05),C组较B组上述指标均下降(P＜0.05).B组血清中IL-8和TNF-α浓度亦比A组增高(P＜0.05),C组较B组下降,但IL-8的浓度差异无统计学意义.B组BALF中IL-8与中性粒细胞绝对计数、TNF-α呈正相关(r=0.735、0.987,P＜0.05);与血清中IL-8和TNF-α、血气分析的所有指标及形态学定量分析的任一指标均无相关性.血清IL-8与上述任一指标亦均无相关性.结论 BALF中的IL-8与COPD的气道炎症密切相关,IL-8与TNF-α相互作用,通过趋化激活中性粒细胞等炎性细胞共同参与COPD发病.泼尼松可能通过抑制IL-8的表达,从而减轻炎症介质和炎性细胞对气道的损害,延缓COPD的进展.     

氟伐他汀抗氧化改善心肌梗死大鼠心室重塑

目的:探讨氟伐他汀长期应用对SD大鼠心肌梗死(AMI)心室重塑过程的影响及其机制.方法:结扎雄性大鼠左冠状动脉前降支,复制心肌梗死模型,将大鼠分为2组,AMI组(n=7)以蒸馏水灌胃,氟伐他汀组(n=8)以氟伐他汀20 mg·kg-1·d-1灌胃;另设假手术2组,分别以蒸馏水和氟伐他汀灌胃.8周后心脏超声、血液动力学、心脏形态学分析;检测血浆总胆固醇(Tch)、一氧化氮(NO)、脂质过氧化物(LPO)、谷胱甘肽过氧化物酶(GPx)和心肌LPO水平;激光共聚焦显微镜检测超氧阴离子和NO的分布;RT-PCR、免疫组化检测诱导型一氧化氮合酶(NOS2)、p22phox的mRNA和蛋白水平表达.结果:与AMI组比较,氟伐他汀组左室舒张末压降低[(18.24±6.58 vs 10.74±4.71)mmHg,P<0.05]、右室相对重量减轻[(0.92±0.19 vs 0.71±0.13)g/kg,P<0.05]、左室后壁厚度减少[(3.04±0.28 vs 2.60±0.36)mm,P<0.05];AMI后射血分数无影响,但肺相对重量减轻[(5.79±2.92 vs 3.69±0.68)g/kg,P<0.05];血浆和心肌LPO水平降低[(8.64±0.59 vs 7.71±0.66)μmol/L,P<0.05;(3.12±0.38 vs 1.93±0.40)ng/μg.pro,P<0.01],NO的过度表达抑制和GPx水平增加[(436.87±47.22 vs 313.78±34.35)mg/dl,P<0.01;(66.13±8.31 vs 79.78±2.38)mg/dl,P<0.05].氟伐他汀干预后增加NOS2、p22phox mRNA和蛋白水平的表达均下降(P<0.01).血浆总胆固醇水平减低,但无显著性差异[(59.40±14.15 vs 48.30±8.83) mg/dl,P>0.05].结论:氟伐他汀参与了改善大鼠心肌梗死后心室重塑过程,其中可能包括抗氧化机制.