致敏大鼠脑皮层和肺气道中干扰素—γ和白介素—4相关性的变化

目的:探讨致敏大鼠抗原攻击后脑皮层和肺气道中干扰素-γ(IFN-γ)和白介素-4(IL-4)出现的相关性变化.方法:观察致敏大鼠吸入抗原诱导的支气管肺灌洗液(BALF)和肺组织切片炎症变化,用ELISA法测定BALF和脑皮层IFN-γ和IL-4水平变化.结果:抗原攻击组BALF中的炎症细胞数目明显高于对照未攻击组(P<0.05).地塞米松(DXM,0.5mg/kg,ip)明显减少BALF中的白细胞总数,几乎完全抑制嗜酸性粒细胞(EOS)和淋巴细胞的聚集,但增加中性粒细胞数目.抗原攻击组的组织学检查积分(EOS浸润、粘膜水肿和上皮损伤)也明显高于对照未攻击组(P<0.05).DXM(0.5 mg/kg,ip)减少支气管和细支气管的EOS数目,改善粘膜水肿和上皮损伤.致敏大鼠抗原攻击后,BALF中的IFN-γ水平降低伴随IL-4升高导致了IFN-γ/IL-4比例下降.与此同时,脑皮层匀浆中也出现相似的改变.DXM(0.5mg/kg,ip)能反转BALF和脑皮层匀浆中的IFN-γ/IL-4比例下降.结论:致敏大鼠抗原攻击后脑皮层和肺气道中的IFN-γ和IL-4出现相关性变化.     

咯利普兰对脂多糖诱导的小鼠急性肺损伤的抑制作用

目的探讨磷酸二酯酶4(PDE4)抑制剂治疗急性肺损伤的作用机制。方法气道内滴入脂多糖3 mg.kg-1制备小鼠急性肺损伤模型,10 min后一次性ip不同剂量咯利普兰或地塞米松;同时设假手术和模型组。给药6 h后处死小鼠,观察肺湿重/干重比值和肺组织的病理改变;用细胞形态学方法计数支气管肺泡灌洗液(BALF)中白细胞和中性粒细胞;考马斯亮蓝法测定BALF总蛋白含量;髓过氧化物酶(MPO)活性测定试剂盒测定肺组织匀浆MPO活性;ELISA法测定肺组织匀浆肿瘤坏死因子α(TNF-α)含量;高效液相色谱法测定肺组织匀浆中cAMP-PDE和PDE4活性。结果小鼠气道内滴入脂多糖6 h后,与假手术组比较,模型组肺湿重/干重比值明显升高;肺组织病理观察可见肺血管和气道周围有大量中性粒细胞浸润;BALF中白细胞和中性粒细胞增多,蛋白含量增加;肺组织MPO活性、TNF-α水平、cAMP-PDE和PDE4活性升高。与模型组比较,咯利普兰(0.1,0.3及1.0 mg.kg-1)和地塞米松(0.5 mg.kg-1)可降低肺组织湿重/干重比值,降低BALF中白细胞总数、中性粒细胞数目和蛋白含量,改善肺组织病理变化,肺组织中MPO活性、TNF-α含量、cAMP-PDE和PDE4活性亦明显降低。结论咯利普兰治疗急性肺损伤的作用机制可能与抑制PDE4活性、抑制中性粒细胞黏附和趋化及降低TNF-α水平有关。     

吡拉米司特在大鼠急性肺损伤模型中降低PDE4活性与TNF-α/IL-10平衡有关

目的观察PDE4活性与TNF-α/IL-10平衡在脂多糖(LPS)诱导的大鼠急性肺损伤模型(ALI)中相互关系,探讨选择性磷酸二酯酶4抑制剂吡拉米司特(piclamilast)对ALI的作用及机制。方法脂多糖(LPS)诱导大鼠ALI模型,设对照组、模型组、吡拉米司特组(1、3、10mg.kg-1)和地塞米松组(1mg.kg-1),常规细胞形态学检测肺泡灌洗液(BALF)和肺组织中中性粒细胞的浸润情况,比色法测定BALF中超氧阴离子自由基(O2.)和中性粒细胞髓过氧化酶(MPO),ELISA法检测肺组织中TNF-α和IL-10含量,高效液相(HPLC)法测定肺组织中PDE4活性。结果①吡拉米司特(1、3、10mg.kg-1)灌胃给予能够抑制BAL中MPO、O2.的增加,改善LPS诱导的大鼠ALI模型BALF中的炎症细胞聚集和肺水肿程度,②吡拉米司特可抑制LPS诱导的大鼠ALI肺组织TNF-α上升(P<0.05～0.01),并能明显提高LPS引起的大鼠ALI肺组织IL-10分泌下降,③大鼠ALI模型肺组织中PDE4活性明显上升(P<0.01),吡拉米司特预处理可抑制PDE4活性的上升,而且其对PDE4活性抑制性变化与TNF-α/IL-10比值的变化基本一致。地塞米松1mg.kg-1也能降低TNF-α和升高IL-10水平,调节TNF-α/IL-10平衡关系,但DXM不能抑制PDE4活性的升高。结论TNF-α/IL-10可能是ALI病理生理学的一对重要的平衡性细胞因子。吡拉米司特可能通过抑制PDE4活性,调节TNF-α/IL-10平衡改善LPS诱导的大鼠ALI。     

致敏大鼠大脑皮层和肺组织中白三烯B4含量一致性升高

目的:检测大鼠哮喘模型脑皮层和肺组织中白三烯(LT)的含量变化,以及抗哮喘药物对该变化的影响。方法:卵白蛋白致敏大鼠,观察支气管肺泡灌洗液(BALF)和肺组织及脑组织切片的炎症性变化,同时用反向高效液相(RP-HPLC)方法检测肺组织及大脑皮层匀浆LT的含量变化。结果:哮喘大鼠BALF内炎症细胞数量和组织学检查评分显著高于正常对照组(P<0.05),地塞米松(DXM,0.5mg/kg)和富马酸酮替芬(KF,5mg/kg)减轻这些炎症变化,RP-HPLC发现在哮喘大鼠肺组织及大脑皮层匀浆中LTB_4含量比正常大鼠显著升高(P<0.05),DXM和KF均可减低肺组织及大脑皮层匀浆液中的LTB_4水平,LTC_4在哮喘大鼠肺组织匀浆液中的含量较正常组显著升高(P<0.05),脑皮层内的含量无变化,DXM和KF均可降低哮喘大鼠肺组织匀浆液中LTC_4的水平(P<0.05)。结论:哮喘大鼠抗原攻击后脑皮层和肺组织中的LTB_4含量都一致性升高,DXM和KF可抑制这种变化。     

川芎嗪调控Gαs/cAMP/PKA信号通路改善哮喘模型大鼠气道炎症的作用研究

目的 探讨川芎嗪对卵蛋白(ovalbumin, OVA)致敏并攻击的幼龄哮喘大鼠Gαs/cAMP/PKA信号活性的影响。方法 通过OVA致敏、攻击复制哮喘大鼠模型,观察川芎嗪干预后哮喘大鼠的气道高反应(airway hyperresponsiveness, AHR)、肺组织病理学变化,检测血清中IL-4、IL-5、IL-13、TNF-α的水平、血浆及肺组织中cAMP水平、肺组织PKA表达、肺组织Gαs、GRK2、CREB基因和蛋白表达。结果 与对照组相比,哮喘大鼠肺阻力增加、肺顺应性降低(P<0.05),肺组织病理改变明显,外周血IL-4、IL-5、IL-13、TNF-α水平明显升高(P<0.05);血浆及肺组织cAMP含量下降,肺组织PKA和CREB表达下调(P<0.01),肺组织中Gαs表达明显下调,而GRK2表达明显上调。与哮喘模型组相比,川芎嗪能够抑制AHR发生,降低哮喘大鼠的肺阻力(P<0.05),并增加肺顺应性,抑制大鼠肺组织炎症细胞浸润以及杯状细胞、纤维增生,明显降低哮喘大鼠外周血IL-4、IL-5、IL-13、TNF-α水平(P<0.01)...     

侧脑室注射组胺对大鼠哮喘样反应可能有调节作用

目的观察组胺侧脑室注射对抗原攻击致敏大鼠引起的支气管收缩反应及气道炎症的影响。方法致敏大鼠侧脑室注射组胺后测定抗原激发前后的气道阻力和肺动态顺应性。计数支气管肺泡灌洗液(BALF)中白细胞总数和分类计数。病理切片观察肺组织炎症细胞浸润情况。结果组胺(0.1μg.只-1)侧脑室注射明显抑制抗原攻击致敏大鼠所致的气道阻力升高和肺动态顺应性的降低,也明显降低BALF内的白细胞总数、嗜酸性粒细胞和中性粒细胞的数量(P<0.01,P<0.01),减少气道粘膜下和血管周围的嗜酸性粒细胞浸润。结论组胺侧脑室注射能抑制大鼠支气管收缩反应及气道炎症,提示中枢组胺水平升高可能对大鼠哮喘样反应有调节作用。     

砒石对哮喘小鼠胞质型磷脂酶A2基因表达及白三烯C4的影响

目的:探讨胞质型磷脂酶A2(cPLA2)mRNA表达、白三烯C4(TLC4)在哮喘发病中的作用及其相互关系,以及砒石对哮喘的治疗作用。方法:建立小鼠卵蛋白哮喘模型,砒石灌胃给药,用逆转录聚合酶链反应方法检测肺组织中cPLA2mRNA表达;ELISA方法检测支气管肺泡灌洗液(BALF)中LTC4含量;微量滴定法测定BALF中PLA2活性。应用新航YP200型压力换能器及Medlab生物信号采集系统检测小鼠肺功能Pmax和T呼T总。结果:哮喘小鼠肺组织cPLA2基因表达水平、BALF中PLA2活性、LTC4水平均较对照组显著升高。0.625、1.25、2.50及5.00mg·kg-1剂量的砒石可下调哮喘小鼠cPLA2mRNA表达,抑制哮喘小鼠BALF中PLA2活性和降低LTC4水平,改善哮喘小鼠肺功能。结论:支气管肺组织中cPLA2基因表达上调、PLA2活性和LTC4水平增高在卵蛋白(OVA)致敏小鼠哮喘发病中起着重要作用。砒石可显著抑制哮喘小鼠肺组织中cPLA2基因的表达,降低哮喘小鼠PLA2活性和降低LTC4水平,改善哮喘小鼠肺功能,具有抗哮喘活性。     

1,8-桉油精对卵白蛋白致哮喘豚鼠的气道高反应性和炎症的抑制作用

目的探讨1,8-桉油精(1,8-cineol)对哮喘豚鼠肺功能的改善作用及其机制。方法豚鼠第0天和第7天ip给予0.5ml含卵白蛋白(OVA)20μg的氢氧化铝凝胶致敏,28d后OVA攻击制备哮喘模型。观察豚鼠OVA攻击后1h,1,8-桉油精10,30和100mg.kg-1对豚鼠吸入OVA后1,2,3,4,10,20和30min时气道阻力(Raw)和肺顺应性(Cdyn)变化及支气管肺泡灌洗液(BALF)中白细胞数和细胞分类的影响,并测量豚鼠肺组织中嗜酸细胞阳离子蛋白(ECP)、白细胞介素4(IL-4)、IL-8和肿瘤坏死因子α(TNF-α)的含量。观察豚鼠OVA攻击后17h再吸入乙酰甲胆碱(MCh)后,1,8-桉油精10,30和100mg.kg-1对Raw和Cdyn及BALF中白细胞数和细胞分类的影响,并测量豚鼠肺组织中ECP,IL-4,IL-8和TNF-α的含量。结果与正常对照组比较,豚鼠OVA攻击后1h,在4min时模型组Raw达到高峰;与模型组比较,1,8-桉油精30和100mg.kg-1明显抑制Raw增加(P<0.05);在3min时模型组Cdyn达到高峰,与模型组比较,1,8-桉油精10,30和100mg.kg-1均能明显抑制Cdyn降低(P<0.05);模型组豚鼠肺组织ECP,IL-4和TNF-α含量明显高于正常对照组(P<0.05);1,8-桉油精100mg.kg-1组ECP,IL-4和TNF-α含量均明显低于模型组(P<0.05),模型组与正常对照组豚鼠肺组织IL-8含量无明显差异。与模型组比较,1,8-桉油精100mg.kg-1能明显减少BALF中白细胞数和嗜酸性粒细胞比例(P<0.05)。致敏豚鼠OVA攻击17h后,模型组豚鼠Raw与正常对照组比较显著升高(P<0.05),模型组豚鼠Cdyn与正常对照组比较有显著性差异(P<0.01),1,8-桉油精100mg.kg-1对MCh引起的Raw的增加有明显的抑制作用,1,8-桉油精10,30和100mg.kg-1对MCh引起的Cdyn降低有明显的改善作用;与模型组相比,1,8-桉油精100mg.kg-1能明显减少BALF中白细胞数和中性粒细胞比例,降低肺组织ECP,IL-8和TNF-α含量(P<0.01);模型组与正常对照组豚鼠肺组织IL-4含量无明显差异;1,8-桉油精30mg.kg-1也能降低哮喘豚鼠肺组织中ECP和TNF-α含量(P<0.01)。结论在哮喘急性发作时,1,8-桉油精通过减少嗜酸性粒细胞,下调嗜酸性粒细胞的活性,从而抑制了哮喘的急性发作。在哮喘迟发相阶段,1,8-桉油精可通过下调IL-8水平,降低TNF-α活性,从而抑制或改善由IL-8水平升高导致的中性粒细胞聚集于支气管肺泡而直接引起的哮喘加重和持续状态。     

隐孔菌多糖对肺组织释放白三烯的影响

目的　观察发酵隐孔菌多糖 (以下称隐孔菌多糖 )对豚鼠肺组织释放白三烯及气管Schultz Dale反应的影响。方法　采用生物检定法和反相高效液相色谱法 (RP HPLC)测定致敏豚鼠肺组织抗原攻击释放过敏性慢反应物质 (SRS A)和正常豚鼠肺组织A2 3187攻击释放白三烯D4(LTD4) ,以及用致敏豚鼠气管Schultz Dale法检测隐孔菌多糖的抗变态反应活性。结果　隐孔菌多糖明显减少抗原攻击致敏豚鼠肺组织SRS A释放量和A2 3 187攻击正常豚鼠肺组织LTD4释放量 ;抑制致敏豚鼠气管Schultz Dale反应 ,IC50 =0 4 9g·L-1。结论　隐孔菌多糖有抑制肺组织释放白三烯和抗变态反应作用     

磷酸二酯酶4B在博来霉素诱导的肺纤维化小鼠肺组织中的表达与作用

目的观察博来霉素诱导的小鼠肺纤维化过程中磷酸二酯酶4B(PDE4B)mRNA和蛋白表达随时间的变化,初步探究PDE4B在小鼠肺纤维化过程中的作用。方法采用气道滴入博来霉素2.5 mg·kg-1制备肺纤维化模型,在造模后第3,7,14,21和28天进行支气管肺泡灌洗并留取肺组织。应用细胞形态学方法计数支气管肺泡灌洗液(BALF)中白细胞总数和分类;ELISA法测定BALF中巨噬细胞炎症蛋白2(MIP2)、白细胞介素6(IL-6)、IL-1β和转化生长因子β1(TGF-β1)含量;胶原试剂盒测定法测定肺组织胶原含量;髓过氧化物酶(MPO)活性测定试剂盒测定组织匀浆液中MPO活性;实时荧光定量PCR方法检测小鼠肺组织中PDE4B mRNA表达;免疫组织化学法检测PDE4B的分布。结果博来霉素气道滴入诱导的肺纤维化随时间持续加重,第28天最明显,可见肺组织明显实质化。BALF中白细胞总数、IL-1β和IL-6在造模后第3天达峰值,分别为正常对照组的22.0,2.0和2.8倍;MPO和TGF-β1在第7天达峰值,分别为正常对照组的1.9和5.5倍;胶原含量、MIP-2和PDE4B mRNA表达从造模后呈持续增长趋势,分别为正常对照组的1.6,2.7和2.6倍。免疫组织化学法检测结果表明,PDE4B分布于炎症细胞和纤维化的肺组织。结论PDE4B在肺纤维化中发挥重要作用,可能是一个特异性的药物作用靶点。     

Effects of ciclamilast, a new PDE 4 PDE4 inhibitor, on airway hyperresponsiveness, PDE4D expression and airway inflammation in a murine model of asthma

PDE4 (phosphodiesterase-4) plays a critical role in pathogenesis of allergic asthma and chronic obstructive pulmonary disease (COPD). PDE4 inhibitors are presently under clinical development for the treatment of asthma and/or COPD. Ciclamilast, a new PDE4 inhibitor, is a piclamilast (RP 73401) structural analogue, but has a more potent inhibitory effect on PDE4 and inflammation in the airway tissues and less side effects than that of piclamilast. In this study, we elucidate primarily on the roles of compound on PDE4 enzyme in physiological and pathological processes in a mouse model of asthma. The sensitized/challenged mice were reexposed to ovalbumin and airway response to inhaled methacholine was monitored. Orally administration of ciclamilast, in a dose-dependent manner, significantly inhibited changes in lung resistance and lung dynamic compliance, as well as upregulation of cAMP-PDE activity, increase of PDE4D mRNA expression, but not PDE4B from lung tissue in the murine model. In addition, the compound dose-dependently reduced mRNA expression of eotaxin, tumor necrosis factor (TNF)-alpha and interleukin (IL)-4, but slightly increased mRNA expression of interferon (IFN)-gamma from lung tissue. Further, levels of eotaxin, TNF-alpha and IL-4, and eosinophil and neutrophil accumulation in bronchoalveolar lavage fluid were also significantly reduced. Pathological examination, goblet cell hyperplasia and inflammatory cells infiltration in lung tissue were suppressed by treatment with ciclamilast. A significant correlation was observed between the increases in PDE4D mRNA expression and airway hyperresponsiveness. These studies confirm that inhibitory effect of ciclamilast on airway hyperresponsiveness includes its inhibiting PDE4D mRNA expression, down-modulating PDE4 activity, anti-inflammation and anti-mucus hypersecretion, and ciclamilast may have therapeutic potential for the treatment of asthma.     

Inhibitory effect of acetamide-45 on airway inflammation and phosphodiesterase 4 in allergic rats

AIM: To determine the effects of acetamide-45 on respiratory function, airway inflammation, and the activity of phosphodiesterase 4 (PDE4) in allergic rats. METHODS: Rats were sensitized by a single intramuscular injection with ovalbumin (OVA) and were challenged with ovalbumin applied by using an aerosol repeatedly for 7 d after 2 weeks. Acetamide-45 at concentrations of 5, 10, or 30 mg/kg was then administered by intraperitoneal injection. Changes in dynamic lung compliance and lung resistance, the accumulation of inflammatory cells in bronchoalveolar lavage, PDE4 activity, and the concentration of interleukin-4 in rat lung tissue were determined. RESULTS: Seven days of treatment with acetamide-45 prevented eosinophil accumulation in allergic rats. At doses of 5, 10, and 30 mg/kg, acetamide-45 decreased lung resistance to 0.20+/-0.04, 0.25+/-0.07, and 0.22+/-0.05 cmH2O.s(-1).mL(-1), respectively (P<0.05 vs OVA), and it also increased dynamic lung compliance to 0.41+/-0.07, 0.39+/-0.06, and 0.42+/-0.09 mL/cmH2O (P<0.05 vs OVA). After being treated with different doses of acetamide-45, the PDE4 activities in lung tissue were 281+/-55, 273+/-57, and 238+/-36 nmol.g(-1).min( -1) (P<0.05 vs OVA), and the concentrations of interleukin-4 in lung tissue were 6.22+/-1.13, 5.95+/-1.20, and 5.68+/-2.20 microg/protein (P<0.05 vs OVA). CONCLUSIONS: Acetamide-45 was found to improve respiratory function and inhibit airway inflammation in this animal model, and the PDE4 activity of lung tissue was obviously inhibited. Acetamide-45 was an effective anti-inflammatory agent in respiratory inflammation, and the mechanism of its action might depend on inhibition of PDE4.     

地龙注射液对哮喘大鼠肺功能的影响

目的观察腹腔注射地龙注射液对哮喘大鼠肺通气功能和气道阻力的影响。方法应用随机分组的方法将大鼠分为实验4周、8周和12周组,每组又分别分为哮喘组、地塞米松干预组、地龙干预组和对照组,每个小组8只动物。用卵蛋白(OVA)腹腔注射致敏加雾化吸入诱喘的方法制成哮喘模型,地龙和地塞米松干预组诱喘前分别给予地龙注射液腹腔注射和地塞米松雾化吸入,应用Maclab数据系统记录分析大鼠肺通气功能和气道阻力。结果实验4周组,各组间肺顺应性差异无统计学意义,哮喘组与其余3组比较,气道阻力明显增高(P<0.01)、每分通气量降低(P<0.01)、呼吸频率增快(P<0.01);实验8周和12周,哮喘组气道阻力明显增加,每分通气量降低,肺顺应性下降,呼吸频率增快(P<0.01或0.05),而地龙组和地塞米松组与对照组比较,气道阻力增高(P<0.05)、呼吸频率增快(P<0.05)、每分通气量降低(P<0.01)、肺顺应性下降(P<0.05);地龙组与地塞米松组间各项肺功能指标差异均无统计学意义。结论地龙注射液可缓解哮喘大鼠支气管痉挛,降低气道阻力,改善肺功能。     

The inhibition of antigen-induced eosinophilia and bronchoconstriction by CDP840, a novel stereo-selective inhibitor of phosphodiesterase type 4.

1. The novel tri-aryl ethane CDP840, is a potent and selective inhibitor of cyclic AMP phosphodiesterase type 4 (PDE 4) extracted from tissues or recombinant PDE 4 isoforms expressed in yeast (IC50S: 4-45 nM). CDP840 is stereo-selective since its S enantiomer (CT 1731) is 10-50 times less active against all forms of PDE 4 tested while both enantiomers are inactive (IC50S: > 100 microM) against PDE types 1, 2, 3 and 5. 2. Oral administration of CDP840 caused a dose-dependent reduction of interleukin-5 (IL-5)-induced pleural eosinophilia in rats (ED50 = 0.03 mg kg-1). The eosinophils in pleural exudates from CDP840-treated animals contained higher levels of eosinophil peroxidase (EPO) than cells from control animals, suggesting a stabilizing effect on eosinophil degranulation. CDP840 was approximately equi-active with the steroid dexamethasone in this model and was 10-100 times more potent than the known PDE 4-selective inhibitors rolipram and RP73401. The activity of CDP840 was not influenced by adrenalectomy, beta-sympathomimetics or beta-sympatholytics. 3. Antigen-induced pulmonary eosinophilia in sensitized guinea-pigs was reduced dose-dependently by CDP840 (0.01-1 mg kg-1, i.p.) and intracellular EPO levels were significantly higher. CDP840 was more potent in these activities than CT1731 or rolipram and comparable in potency to RP73401. 4. Rolipram or CDP840 were less active than dexamethasone in preventing neutrophil accumulation, or exudate formation in carrageenan-induced pleurisy in rats and thus do not exhibit general anti-inflammatory activity. 5. In sensitized guinea-pigs, aerosols of the antigen ovalbumin caused a dose-dependent bronchoconstriction demonstrated by an increase in pulmonary inflation pressure. Administration of CDP840 (0.001-1.0 mg kg-1, i.p.), 1 h before antigen challenge, resulted in dose-dependent reduction in response to antigen. This activity was not due to bronchodilatation since higher doses of CDP840 (3 mg kg-1) did not significantly change the bronchoconstrictor response to histamine. Rolipram was approximately 10 times less active than CDP840 in preventing antigen-induced bronchoconstriction. 6. These results confirm the observations that selective PDE 4 inhibitors reduce antigen-induced bronchoconstriction and pulmonary eosinophilic inflammation. CDP840 is more potent than rolipram in inhibiting native or recombinant PDE 4. Unlike the recently described potent PDE 4 inhibitor RP73401, CDP840 is more active than rolipram in the rat IL-5 model following oral administration. The novel series of tri-aryl ethanes, of which CDP840 is the lead compound, could be the basis of an orally active prophylactic treatment for human asthma.     

茶多酚对奥氮平诱导肥胖大鼠的减肥作用及其机制

目的探讨茶多酚对奥氮平诱导肥胖大鼠的减肥作用及其机制。方法 SD雌性大鼠50只,随机分为正常对照组(10只)和奥氮平诱导肥胖模型组(40只)。肥胖模型组于黑暗时相前1h奥氮平1.2 mg·kg~(-1)·d~(-1)灌胃,正常对照组给予等容量蒸馏水,连续2 wk。于wk 3开始,再将肥胖模型大鼠随机分为4组:模型组、西布曲明(2.5 mg·kg~(-1)·d~(-1))组、茶多酚低(150 mg·kg~(-1)·d~(-1))剂量组和茶多酚高(300 mg·kg~(-1)·d~(-1))剂量组,每组10只。连续给药5 wk。观察大鼠体重、肾和子宫周围脂肪湿重,计算Lee's指数和脂肪系数,测定血清瘦素、脂联素水平以及超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。结果与正常对照组相比,模型组大鼠体重和脂肪湿重及Lee's指数和脂肪系数均增加,血清瘦素水平升高,脂联素水平降低(P<0.05)。与模型组比较,茶多酚低、高剂量组大鼠体重和脂肪湿重降低,Lee's指数、脂肪系数降低,SOD活性增加,MDA含量减少(P<0.05)。与模型组比较,茶多酚高剂量组血清脂联素水平升高(P<0.05),瘦素水平无显著差异(P>0.05)。结论茶多酚对奥氮平诱导的肥胖大鼠有减肥作用,其作用机制可能与增强脂联素的调节和提高抗氧化能力有关。     

Effects of inhibition of PDE4 and TNF-alpha on local and remote injuries following ischaemia and reperfusion injury

1. The effects of phosphodiesterase (PDE)4 and TNF-alpha inhibition were assessed on the local and remote injuries following intestinal ischaemia and reperfusion (I/R) injury in rats. 2. The PDE4 inhibitor rolipram dose-dependently (1 - 10 mg kg(-1)) suppressed the local (intestine) and remote (lung) increases in vascular permeability and neutrophil recruitment following mild I/R injury. SB207499 (ariflo), a structurally-distinct PDE4 inhibitor, also suppressed the injuries following mild I/R injury. 3. In a severe model of I/R injury, treatment with rolipram (10 mg kg(-1)) partially reversed the local and remote increases in vascular permeability, neutrophil recruitment, intestinal haemorrhage and intestinal LTB(4) concentrations. The anti-TNF-alpha anti-serum was more effective than rolipram at inhibiting local and remote injuries and prevented the lethality associated with severe I/R. 4. Rolipram and anti-TNF-alpha prevented the increase in the concentrations of TNF-alpha in the lung and intestine, but rolipram only partially inhibited the elevation of this cytokine in serum. Rolipram had little effect on the increases of IL-1 beta concentrations in lung and serum, whereas treatment with anti-TNF-alpha markedly increased the concentration of this cytokine. Concentrations of IL-10 rose significantly in the lung and serum and these increases were blocked by rolipram or anti-TNF-alpha. 5. The capacity of PDE4 inhibitors to block the recruitment of neutrophils into tissues, the production of LTB(4) and of the pro-inflammatory cytokines TNF-alpha, IL-1 beta and IL-6 appear to underlie their anti-inflammatory effects in our model of I/R injury. Overall, PDE4 inhibition was less effective than inhibition of TNF-alpha for protection against I/R injury.     

Inhibition of Antigen-induced Pulmonary Eosinophilia and Neutrophilia by Selective Inhibitors of Phosphodiesterase Types 3 or 4 in Brown Norway Rats

Summary: Rolipram, a phosphodiesterase type 4 (PDE4)-selective inhibitor, has been demonstrated to inhibit antigen-induced pulmonary eosinophilia in guinea pigs and monkeys, suggesting that PDE4-selective inhibitors could be useful for treating asthma. Although the rat is used extensively in preclinical drug development, a pulmonary antiinflammatory effect of PDE4 inhibition has not been demonstrated in this species. Therefore, we examined the effects of rolipram, CI-930 (PDE3-selective inhibitor), zaprinast (PDE5-selective inhibitor) and aminophylline on antigen-induced pulmonary inflammatory cell influx in Brown Norway rats. Two weeks after sensitization rats were exposed to aerosolized ovalbumin and 24 h later bronchoalveolar lavage (BAL) was performed for determinations of total cell counts and cell type differentials. The resulting 10-fold increase in total cell counts was due primarily to an increase in eosinophils (from 0.06 to 11.0 × 10⁶) and neutrophils (from 0.02 to 12 × 10⁶). Rolipram, CI-930 and aminophylline, given p.o. before and after antigen challenge, each completely inhibited eosinophil influx, with B.I.D. ED₅₀ values of 0.5, 0.4 and 39 mg/kg, respectively. Rolipram, CI-930 and aminophylline each completely inhibited neutrophil influx as well, with B.I.D. ED₅₀ values of 0.1, 0.5 and 20 mg/kg, respectively. Denbufylline and milrinone (10 mg/kg p.o.) also inhibited eosinophil and neutrophil influx, consistent with PDE4 and PDE3 inhibition as the mechanisms of action of rolipram and CI-930, respectively. In contrast, zaprinast was inactive at 0.3-30 mg/kg. However, the β₂ agonist salbutamol greatly inhibited antigen-induced pulmonary eosinophilia and neutrophilia, with p.o. B.I.D. ED₅₀ values of 2.1 and 2.3 mg/kg, respectively, indicating that drugs which increase intracellular cAMP levels by one of several mechanisms can inhibit antigen-induced pulmonary inflammation in rats. In conclusion, these results demonstrate that PDE4 inhibitors produce pulmonary antiinflammatory effects in rats. Furthermore, these results suggest that PDE3 inhibitors also can produce pulmonary antiinflammatory effects in vivo.