1,6-二磷酸果糖镁对异丙肾上腺素所致大鼠心肌损伤的保护作用

研究 1 ,6-二磷酸果糖镁 ( FDP- Mg)对异丙肾上腺素 ( Iso)所致心肌损伤的保护作用 .大鼠 sc Iso( 8mg· kg-1· d-1,3d)造成心肌损伤模型 ,测定心肌组织和血清肌酸激酶 ( CK) ,乳酸脱氢酶( LDH) ,超氧化物歧化酶 ( SOD)活性及丙二醛( MDA) ,Mg2 ,P和 K 含量 .结果 :每天给予 Iso的同时给予 FDP- Mg( 2 50 - 1 0 0 0 mg· kg-1· d-1,3d)能明显降低血清 CK,LDH水平 ,抑制心肌组织中 CK,LDH释放 ,提高血清和心肌 SOD活性 ,降低MDA水平 ,提高心肌及血清 Mg2 和 P含量 ,降低血清 K 浓度。综合了 FDP- Na2 ( 530 mg· kg-1·d-1,3d)和硫酸镁 ( 1 50 mg· kg-1· d-1,3d)的作用特点。结果表明 ,FDP- Mg对 Iso所致大鼠心肌损伤具有保护作用 ,与其抗氧化及改善心肌代谢有关 .     

内皮素受体阻断剂CPU0213改善糖尿病大鼠心肌病由抑制NADPH氧化酶所介导

目的:研究糖尿病大鼠心肌病中由激活的NADPH氧化酶导致的损害,可由内皮素受体拮抗剂CPU0213逆转。方法:SD大鼠一次i.p.链脲佐菌素60mg/kg造成大鼠糖尿病模型,治疗组在后4周给予CPU0213(100mg/kg,p.o.)和氨基胍(100mg/kg,p.o.)治疗,连续4周。结果:CPU0213与氨基胍降低血糖效应不明显,但可改善心肌肥厚、降低心肌内皮素-1(ET-1)和氧化应激水平。CPU0213和氨基胍明显抑制高糖温孵的心肌细胞NADPH氧化酶p22phox和p67phox亚基的mRNA和蛋白过表达。结论:内皮素受体拮抗剂CPU0213和氨基胍改善糖尿病大鼠心肌病,由抑制心肌中NADPH氧化酶过表达所介导。     

越桔原花青素对大鼠心肌纤维化作用的影响

目的探讨越桔原花青素(procyanidin from Vaccini-um,PC)对大鼠心肌纤维化作用的影响及其机制。方法体内实验以异丙肾上腺素(isoprenaline,Iso)5 mg.kg-1.d-1背部皮下注射,构建大鼠心肌纤维化模型,同时以灌胃方式给予PC 100、200、400 mg.kg-1.d-1,分光光度法检测左心室心肌组织中羟脯氨酸(hydroxyproline,Hyp)、丙二醛(ma-londialdehyde,MDA)含量和超氧化物歧化酶(superoxide dis-mutase,SOD)活性;电镜观察心肌超微结构变化。体外实验采用细胞培养技术以血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)建立新生大鼠心肌成纤维细胞(cardiac fibroblast,CFb)增殖模型,给予25、50和100 mmol.L-1的PC干预。采用四唑盐(MTT)比色法测定细胞增殖;ELISA法测定Ⅰ、Ⅲ胶原及转化生长因子β1(TGF-β1)蛋白的含量。结果PC可剂量依赖性地降低心肌组织中Hyp、MDA含量、增强SOD活性,同Iso组比较差异有统计学意义(P<0.05或P<0.01),电镜结果显示:PC可缓解Iso所导致的心肌损伤。体外实验部分PC(25、50和100 mg.L-1)可抑制AngⅡ诱导的CFb增殖、胶原合成增加及TGF-β1蛋白含量增多,与AngⅡ组比较差异具有统计学意义(P<0.05或P<0.01)。结论PC可通过抗氧化作用,抑制CFb的增殖及胶原的合成,进而抑制大鼠心肌纤维化,对心肌具有一定的保护作用。     

谷胱甘肽复方注射液对免疫性肝纤维化大鼠肝组织MMP-13及TIMP-1表达的影响

目的:研究谷胱甘肽复方注射液(CGII)对猪血清所致免疫性肝纤维化大鼠肝组织中基质金属蛋白酶-13(MMP-13)以及组织抑制剂-1(TIMP-1)mRNA和蛋白表达的影响。方法:猪血清腹腔注射8周,复制大鼠免疫性肝纤维化模型。将雄性Wistar大鼠随机分为正常组(N组)、模型组(M组)、还原型谷胱甘肽(GSH)组、CGII高(CH,10.8 mg·kg-1)、中(CM,5.4 mg·kg-1)、低(CL,2.7 mg·kg-1)剂量组,第6周末取大鼠肝组织行病理切片,苏木素-伊红(HE)染色,观察病理学改变;用实时荧光定量PCR和Western Blot检测大鼠肝组织中MMP-13以及TIMP-1 mRNA和蛋白的表达。结果:病理结果显示,与模型组相比,CH,CM和CL各组大鼠肝纤维化程度均有明显改善,大鼠肝组织内TIMP-1 mRNA及蛋白水平显著降低,MMP-13 mR-NA和蛋白表达水平明显升高。结论:CGII可明显减轻免疫性大鼠肝纤维化程度,其机制可能与下调TIMP-1 mRNA及蛋白水平,上调MMP-13 mRNA及蛋白水平,改善肝纤维化中MMP-13/TIMP-1的不平衡表达有关。     

淫羊藿苷抑制TGF-β1/Smad2信号通路改善压力超负荷所致的大鼠心肌纤维化

目的 观察淫羊藿苷(icariin,Ica)对大鼠压力超负荷所诱导的心肌纤维化的干预作用,并研究其作用机制是否与Ica影响左心的转化生长因子β1(transforming growth factor-β1,TGF-β1)、Smad2的表达有关.方法 SD大鼠(n=5)随机分为假手术组、心肌纤维化模型组、Ica低、高剂量干预模型组.用腹主动脉缩窄术致压力超负荷心肌纤维化模型,Ica低、高剂量组造模后次日给予Ica 40、80 mg·kg-1(ig,qd),持续50 d.期间观察大鼠的一般情况,d 51检测左心指数;用Masson染色法观察心肌间质纤维化情况,用PCR和免疫组化法分别检测心肌TGF-β1、Smad2的mRNA和蛋白表达变化.结果 压力超负荷组大鼠左室心肌纤维化程度明显,并伴左心指数增高,左室TGF-β1、Smad2 mRNA和蛋白表达均明显上升.而Ica能明显改善上述病理改变,降低TGF-β1、Smad2 mRNA和蛋白的表达.结论 Ica具有抗压力超负荷所致大鼠心肌纤维化的作用,其机制至少部分与其抑制TGF-β1/Smad2信号通路有关.     

环孢菌素A对大鼠血压的影响

目的 研究环孢菌素A(CsA)对大鼠血压的影响及机制。方法 用离体血管环技术研究CsA对5-羟色胺(5-HT)受体介导的肠系膜动脉平滑肌收缩功能的影响，用蛋白质印迹法检测5-羟色胺受体以及5′-腺嘌呤核苷酸依赖的蛋白激酶和丝裂原活化蛋白激酶(AMPK/MAPK)信号通路相关蛋白的表达水平。将SD大鼠随机分为3组：正常对照组、CsA 15 mg·kg^-1组和CsA 25 mg·kg^-1组，CsA组皮下注射不同剂量的CsA,每天1次，连续21 d,正常对照组皮下注射等体积大豆油。每周测量大鼠的收缩压与舒张压。给药3周后，用离体血管环技术观察动脉收缩量效曲线的变化，用蛋白质印迹法检测5-羟色胺受体蛋白的表达水平。结果 CsA可以增强5-羟色胺引起的血管收缩并使5-羟色胺受体蛋白的表达增加，AMPK通路激活剂AICAR和MAPK通路抑制药U0126、SP600125、SB203580可以抑制环孢菌素A诱导的血管收缩反应并降低5-羟色胺受体以及p-ERK1/2、p-JNK1/2、p-P38蛋白的表达。动物实验结果表明，皮下注射CsA 3周后，正常对照组...     

内皮素受体拮抗剂CPU0213对异丙肾上腺素心肌病SERCA2a表达的改善作用

目的：研究异丙肾上腺素心肌病模型心肌细胞肌浆网钙ATP酶（sarco-endoplasmic reticulum ATPase 2a,SERCA2a）表达的改变,以及新型内皮素受体拮抗剂CPU0213的治疗作用。方法：雄性SD大鼠皮下给予异丙肾上腺素（2mg·kg^-1·d^-1）10d,治疗组动物在第6到第10天皮下给予CPU0213（30mg·kg^-1·d^-1）。各组动物颈动脉插管记录心功能指标：左心室收缩压（LVSP）,左心室舒张末期压（LVEDP）,和左心室压力变化最大速率（±dp/dtmax）。左心室心肌组织SERCA2a的mRNA及蛋白表达分别用逆转录聚合酶链反应（RT-PCR）和蛋白免疫印迹法（Western blotting）测定。结果：异丙肾上腺素引起左心室收缩和舒张功能明显下降,同时SERCA2a的mRNA及蛋白表达均显著下调（P〈0.05）。CPU0213显著提高SERCA2a表达（P〈0.05）,明显改善心功能（P〈0.05）。结论：CPU0213可通过逆转肌浆网钙调控蛋白SERCA2a的表达下调,使异丙肾上腺素引起的心功能下降得以恢复。本实验证明SERCA2a是β受体过度激活引发心衰过程中的重要靶点。内皮素受体介导了β受体过度激活状态下SER-CA2a的表达下调,是内皮素受体拮抗剂治疗心衰的重要依据之一。     

地塞米松抑制慢性心衰大鼠心肌中内皮素信号通路的过度激活而改善心肌纤维化

目的：观察地塞米松对慢性心衰大鼠心肌中内皮素（ET）信号通路的过度激活与氧化应激的干预作用。方法：雄性SD大鼠,通过冠脉结扎6周造成慢性心衰模型。分为慢性心衰组、地塞米松组,另设假手术组作为阴性对照。地塞米松组动物在饮水中按1μg/mL的浓度给予地塞米松治疗。连续治疗6周后,取心脏进行Masson三色法染色,以检测心肌纤维化;RT-PCR法检测心肌组织中ETA受体、NF-κB和一氧化氮合酶（iNOS）的基因表达水平。结果：与假手术组相比,慢性心衰组大鼠心肌纤维化显著,地塞米松能有效改善心衰大鼠心肌组织的纤维化;心衰大鼠心肌组织中ETA受体、NF-κB和iNOS的基因表达水平明显上调,而地塞米松可使心衰大鼠心肌中ETA受体、NF-κB和iNOS的基因表达水平显著下调。结论：地塞米松通过下调ETA受体,抑制ET信号通路的过度激活和抗氧化作用,有效改善慢性心衰大鼠的心肌纤维化。     

果糖二磷酸锶改善糖尿病大鼠睾丸病变及对前原内皮素和内皮素转变酶表达的影响

目的:研究果糖二磷酸锶(FDP-Sr)对糖尿病睾丸病变的改善,与丙酸睾酮对比,并初步探讨其可能机制。方法:链脲佐菌素致糖尿病雄性大鼠8周,在后4周,分别每日灌胃FDP-Sr(50,100,200mg/kg)以及丙酸睾酮(4mg/kg,s.c.治疗),测血中睾酮、谷胱甘肽过氧物酶(GSHpx)、睾丸中内皮素-1(ET-1)系统中前原ET-1(前原内皮素,ppET-1)和ET转变酶(ECE)的mRNA表达,观察睾丸组织学改变。结果:糖尿病大鼠睾丸曲细精管萎缩明显,血中睾酮、GSHpx明显降低,ppET-1和ECE呈高表达。上述改变被FDP-Sr明显改善,丙酸睾酮作用不明显。结论:FDP-Sr治疗糖尿病睾丸病变优于丙酸睾酮,可能与抑制睾丸中内皮素系统的高表达相关。     

异丙肾上腺素致大鼠心肌肥厚时心肌细胞核Ca2+转运

目的观察异丙肾上腺素(Iso)致大鼠心肌肥厚模型心肌细胞核45Ca2+摄取、钙释放通道肌醇1,4,5-三磷酸(IP3)受体(IP3R)和ryanodine受体(RyR)的动力学变化,以探讨细胞核Ca2+的转运是否参与心肌肥厚发生.方法 Iso(sc 20、10和5 mg·kg-1剂量递减3 d,3 mg·kg-1维持7 d)制备大鼠心肌肥厚模型,用差速离心和蔗糖密度梯度离心提纯心肌细胞核,用45Ca2+同位素法测定细胞核钙摄取,用[3H]标记配体分析心肌细胞核IP3R和RyR的动力学特点.结果与对照组相比,Iso可导致大鼠心肌显著肥大,伴有显著心肌纤维化;心肌细胞核膜IP3R与其配体的最大结合容量(Bmax)减少23.4%(P<0.05),解离常数(Kd)无明显变化(P>0.05);细胞核RyR的Bmax增加59.9%(P<0.01),Kd无明显变化(P>0.05);45Ca2+摄取显著低于对照组(P<0.01),最大摄取与对照组相比降低62%(P<0.01),达半数最大摄取时[Ca2+]无显著变化.结论Iso导致大鼠心肌肥厚纤维化发生过程中,心肌细胞核45Ca2+摄取能力降低,核上RyR数目上调,而IP3R数目下调,受体亲和力无变化,提示心肌细胞核钙调节系统参与心肌肥厚的发生过程.     

大黄素对环孢素A在大鼠体内的药代动力学

目的评价中药成分大黄素对大鼠灌服环孢素A(CsA)的药代动力学。方法 60只雄性SD大鼠按体重进行随机分为5组,分别灌服CsA+60 mg.kg-1高剂量蒸馏水;CsA+30 mg.kg-1低剂量酮康唑;CsA+大黄素(60 mg.kg-1);CsA+大黄素(30 mg.kg-1);1～3 d大黄素,第4 d灌服CsA+大黄素。用HPLC-MS法测定全血中CsA的浓度,kinetica软件计算主要药代动力学参数,用SPSS17.00进行统计学分析。结果阳性对照组与空白对照组药代动力学参数除吸收速率外均有显著性差异;高剂量大黄素组使其较快达到峰浓度(P<0.05);低剂量大黄素组药代动力学参数与空白对照组比较无显著性差异;服用3 d大黄素后,最后1 d灌服CsA+大黄素组的吸收速率和峰浓度与空白对照组比较有显著性差异(P<0.05)。结论大黄素对CsA的生物利用度和代谢无明显影响。     

链霉素对大鼠连续灌服环孢素A后血药浓度及肾损伤的影响

目的:探讨链霉素对大鼠连续灌服环孢素A(CsA)后血药浓度及肾损害的影响。方法:取大鼠40只,随机分为空白组(灌服橄榄油)、模型组(灌服CsA 20mg·kg-1)、链霉素高剂量组(灌服CsA 20mg·kg-1+肌肉注射链霉素180mg·kg-1)、链霉素低剂量组(灌服CsA 20mg·kg-1+肌肉注射链霉素60mg·kg-1),给予相应药物,每天1次,连续6周,分别于给药前和给药后2、4h眼球后静脉丛采血,每7天采血1次,测定CsA血药浓度(c0、c2、c4),及生化指标血肌酐、血尿素氮,实验结束处死大鼠,进行肾间质损伤程度评定。结果:与模型组比较,链霉素高、低剂量组大鼠前3周的c0、c2、c4均降低(高剂量组降低显著,P<0.05或P<0.01或P<0.001),5周内血肌酐、血尿素氮无明显变化;同时肾损伤程度未加重。结论:CsA与链霉素联用时,应注意监测CsA的血药浓度及生化指标,适当调整给药剂量,并且密切关注患者肾功能变化。     

Selective angiotensin II type 1 receptor blockade ameliorates cyclosporine nephrotoxicity.

Nephrotoxicity associated with cyclosporine A (CsA) administration is characterized by marked renal vasoconstriction, interstitial fibrosis and arteriolar hypertrophy. The molecular mechanisms of CsA nephrotoxicity are not well characterized, but previous studies have demonstrated that angiotensin II (Ang II), the primary mediator of renin-angiotensin system (RAS) cascade plays a role in its pathogenesis. Recent studies also suggest an involvement of reactive oxygen species (ROS) in CsA nephrotoxicity. There is emerging evidence that Ang II induces oxidative stress in vitro and in vivo. The aims of this study were to investigate the role of Ang II-induced oxidative stress in CsA nephrotoxicity, and to examine the effects of the insurmountable Ang II type 1 (AT (1)) receptor antagonist, candesartan on CsA-induced nephrotoxicity in rats. Candesartan cilexetil (1.0 mg kg (-1), perorally (p.o.), once a day) was administered 24 h before and 21 days concurrently with CsA (20 mg kg(-1), subcutaneously (s.c.)). Tissue lipid peroxidation was measured as thiobarbituric acid reacting substances (TBARS). Renal function was assessed by estimating serum creatinine, blood urea nitrogen (BUN), creatinine and urea clearance. Renal morphological alterations were assessed by histopathological examination of Haematoxylin-Eosin, PAS and Mason's trichome stained sections of the kidneys. CsA (20 mg kg (-1), s.c.) administration for 21 days produced elevated levels of TBARS and deteriorated the renal function as assessed by increased serum creatinine, BUN and decreased creatinine and urea clearance as compared to vehicle treated rats. The kidneys of CsA-treated rats showed severe striped interstitial fibrosis, arteriolopathy, glomerular basement thickening, tubular vacuolisation and hyaline casts. Candesartan cilexetil (1.0 mg kg (-1)) markedly reduced elevated levels of TBARS, significantly attenuated renal dysfunction and morphological changes in CsA-treated rats. These results clearly demonstrate the pivotal role of Ang II-induced oxidative stress and the therapeutic potential of AT (1)receptor antagonists in ameliorating CsA-induced nephrotoxicity.     

Comparison of enalapril and valsartan in cyclosporine A-induced hypertension and nephrotoxicity in spontaneously hypertensive rats on high-sodium diet

1. We compared the effects of the angiotensin converting enzyme (ACE) inhibitor enalapril and the angiotensin AT(1) receptor antagonist valsartan in cyclosporine A (CsA)-induced hypertension and nephrotoxicity in spontaneously hypertensive rats (SHR). 2. SHR (8 - 9 weeks old) on high-sodium diet were given CsA (5 mg kg(-1)d (-1) s.c. ) for 6 weeks. The rats were treated concomitantly either with enalapril (30 mg kg(-1)d (-1) p.o.) or valsartan (3 or 30 mg kg(-1) d (-1) p.o.). To evaluate the role of bradykinin in the action of enalapril, some rats received a bradykinin B(2) receptor antagonist icatibant (HOE 140, 500 microg kg(-1) d (-1) s.c.) during the last 2 weeks of enalapril treatment. 3. Blood pressure was recorded every second week by tail cuff method. Renal function was measured by serum creatinine, creatinine clearance and urinary excretion of proteins at the end of the experiment. The activity of the renal kallikrein-kinin system was estimated by urinary kallikrein excretion. 4. CsA caused hypertension, impaired renal function and induced morphological nephrotoxicity with glomerular damage and interstitial fibrosis. Enalapril and the lower dose of valsartan attenuated the CsA-induced hypertension to the same extent, while the higher dose of valsartan totally abolished it. Icatibant did not reduce the antihypertensive effect of enalapril. Urinary kallikrein excretion was similar in all groups. 5. Enalapril and valsartan equally prevented the CsA-induced deterioration of kidney function and morphology. 6. The renin-angiotensin but not the kallikrein-kinin system plays a crucial role in CsA-toxicity during high intake of sodium in SHR.     

Inhibitory effect of tea polyphenols on transforming growth factor-beta1 expression in rat with cyclosporine A-induced chronic nephrotoxicity.

AIM: To investigate the inhibitory effect of tea polyphenols (TP) on the transforming growth factor-beta1 (TGF-beta1) expression in rat model of cyclosporine A (CsA)-induced chronic nephrotoxicity. METHODS: The rat model of CsA-induced chronic nephrotoxicity was used, 4 groups of rats were respectively treated with vehicle (0.1 mL/kg/d sc), TP (80 mg/kg/d ig), CsA (15 mg/kg/d sc) and TP plus CsA (CsA 15 mg/kg/d sc+TP 80 mg/kg/d, ig). At the end of day 28 of treatment, serum and urine are analyzed for creatinine clearance, kidney tissue for pathologic analysis. The TGF-beta1 mRNA and its protein expression were detected by RT-PCR, immunohistochemistry, and Western blot. RESULTS: CsA-treated rats had increased renal expression of TGF-beta1 mRNA and its protein, compared with the vehicle- or TP-treated controls. The renal function and interstitial fibrosis were ameliorated and renal expression of TGF-beta1 mRNA and its protein was decreased in animals treated with CsA plus TP, compared with animals treated with CsA alone (P<0.05). CONCLUSION: TP significantly inhibits renal expression of TGF-beta1 in rat model of cyclosporine-induced chronic nephrotoxicity, suggesting that the decreased renal expression of TGF-beta1 exerted by TP is one of mechanisms to protect renal function and tissue structure.     

Quercetin, a bioflavonoid, protects against oxidative stress-related renal dysfunction by cyclosporine in rats.

Nephrotoxicity is the most common and clinically important side effect of cyclosporine (CsA). Recent evidence suggests that reactive oxygen species (ROS) play an important role in CsA nephrotoxicity. This study was designed to demonstrate the role of oxidative stress and its relation to renal dysfunction and to investigate the effects of quercetin, a bioflavonoid with antioxidant properties, in CsA-induced nephrotoxicity. Quercetin (0.5 and 2.0 mg/kg i.p.) was administered 24 h before and concurrently with CsA (20 mg/kg s.c.) for 21 days. Tissue lipid peroxidation was measured as thiobarbituric acid reacting substances (TBARS). Renal function was assessed by estimating plasma creatinine, blood urea nitrogen (BUN), creatinine and urea clearance. Renal morphological alterations were assessed histopathologically. Pretreatment with CsA (20 mg/kg s.c.) for 21 days produced elevated levels of TBARS and deteriorated renal function as assessed by increased plasma creatinine, BUN and decreased creatinine and urea clearance as compared to vehicle-treated rats. The kidneys of CsA-treated rats showed severe striped interstitial fibrosis, arteriopathy, glomerular basement thickening, tubular vacuolization and hyaline casts. Quercetin (2 mg/kg) markedly reduced elevated levels of TBARS and significantly attenuated renal dysfunction and morphological changes in CsA-treated rats. It is likely that quercetin, due to its antioxidant properties, prevented CsA-induced ROS and consequently CsA nephrotoxicity. These results clearly demonstrate the pivotal role of oxidative stress and its relation to renal dysfunction, and also point to the therapeutic potential of the natural antioxidant quercetin in CsA-induced nephrotoxicity.     

The protective effect of erdosteine against cyclosporine A-induced cardiotoxicity in rats

Cyclosporine A (CsA) is a frequently used immunosuppressive agent in transplant medicine to prevent rejection and in the treatment of autoimmune diseases. However, CsA generates reactive oxygen species, which causes nephrotoxicity, hepatotoxicity and cardiotoxicity. The use of antioxidants reduces the adverse effects of CsA. The aim of this study is to determine the protective effects of erdosteine on CsA-induced heart injury through tissue oxidant/antioxidant parameters and light microscopic evaluation in rats. CsA cardiotoxicity was induced by administrating an oral dose of 15mg/kg CsA daily for 21 days. The rats were divided into four groups: control group (n=4), CsA administrated group (15mg/kg, n=5), CsA+erdosteine administrated group (10mg/kg day orally erdosteine, n=4) and only erdosteine administrated group (10mg/kg day orally n=5). CsA treated rats showed increase in the number of infiltrated cells and disorganization of myocardial fibers with interstitial fibrosis. The number of infiltrated cells, disorganization of myocardial fibers and interstitial fibrosis was diminished in the hearts of CsA-treated rats given erdosteine. The malondialdehyde, the protein carbonyl content and nitric oxide levels were increased in the cyclosporine A group in comparison with the control and CsA plus erdosteine groups. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were higher in CsA plus erdosteine group than CsA group. However, the CAT, GSH-Px and SOD activities were significantly lower in CsA group than in control group and erdosteine group. These results suggest that erdosteine has protective effect against CsA-induced cardiotoxicity.     

Enhanced Selective Lymphatic Delivery of Cyclosporin A by Solubilizers and Intensified Immunosuppressive Activity Against Mice Skin Allograft

The absorption and lymphatic delivery of a new immunosuppressive drug, cyclosporin A (CsA), were studied in rats by administering CsA orally after solubilization with HCO-60 (polyoxyethylated hydrogenated castor oil), sugar ester, and oils. After the administration of solubilized CsA (7 mg/kg) to rats with thoracic lymph duct cannulas, both plasma and lymph CsA levels were measured over 6 hr. The lymph CsA levels were strongly affected by the solubilizers. The rank order of the solubilizers in enhancing lymph absorption was HCO-60 (57 µg/ml) > sugar ester (46 µg/ml) > sesame oil (3.5 µg/ml) > linoleic acid (0.4 µg/ml), where the parentheses show the maximum lymph CsA levels. Plasma CsA levels were below 2 µg/ml in each group of animals and were barely altered by the solubilizers. These results support the selective lymphatic delivery of CsA with solubilizers such as HCO-60 and sugar ester. The immunosuppressive activity of CsA (1 mg/kg) solubilized with HCO-60 was nearly equivalent to the sesame oil solution with 7 to 15 mg/kg CsA in the skin-allograft mice model.     

Taurine attenuates hypertension and renal dysfunction induced by cyclosporine A in rats

Cyclosporine A (CsA) is the first-line immunosuppressant used for the management of solid organ transplantation and autoimmune diseases. Nephrotoxicity is the major limitation of CsA use. Recent evidence suggests that reactive oxygen species (ROS) play an important role in mediating CsA-induced hypertension and nephrotoxicity. Taurine, the major intracellular free beta-amino acid, is known to be an endogenous anti-oxidant and membrane-stabilizing agent. The present study was designed to investigate the effects of taurine on CsA-induced oxidative stress, hypertension and renal dysfunction. 2. Animals were assigned into four groups of seven rats each as follows: (i) control group, receiving vehicle (olive oil; 1 mL/kg, s.c.); (ii) CsA group, given CsA (25 mg/kg per day, s.c.) for 21 days; (iii) taurine group, supplemented with taurine (1% in the drinking water); and (iv) taurine + CsA group, treated with taurine 3 days before and concurrently during CsA injections for 21 days. 3. Cyclosporine A administration elevated blood pressure, reduced serum nitric oxide (NO) levels and deteriorated renal function, as assessed by increased serum creatinine levels and proteinuria and reduced urine flow rate and creatinine clearance compared with vehicle-treated rats. Cyclosporine A induced oxidative stress, as indicated by increased renal tissue concentrations of thiobarbituric acid-reactive substances and reduced concentrations of renal glutathione, glutathione peroxidase and superoxide dismutase. Conversely, no change was noted in renal catalase activity. Moreover, the kidneys of CsA-treated rats showed interstitial inflammation and renal tubular atrophy. 4. Taurine markedly reduced elevated blood pressure, attenuated renal dysfunction and the reduction in serum NO levels and counteracted the deleterious effects of CsA on oxidative stress markers. Furthermore, taurine ameliorated CsA-induced morphological changes. 5. These data clearly indicate the protective potential of taurine against CsA-induced hypertension and nephrotoxicity and suggest a significant contribution of its anti-oxidant property to this beneficial effect.     

L—精氨酸对环孢素A急性肾脏毒性保护作用的实验研究

目的：观察L－精氨酸（L－arg)对环孢素A（CsA)急性肾脏性的保护作用,方法,健康雄性SD大鼠,随机分为四组,G1组,对照组,G2组：C sA50mg/kg,G3组,GsA50mg/kg L-arg300mg/kg,G4组：CsA50mg/kg L-硝基忱酸甲基酯（L－NAME）5mg/kg,每 天灌胃,实验至第7天末收集尿液,采血测定血肌酐,尿素氮,尿NO^-2/NO^-3,取肾脏行组织病理学检查和组织定量分析,结果,G2组有明显肾中毒表现,G3组肾损害较G2,G4组减轻,G3组尿内NO2^-/NO^-3明显增加,G4组尿内NO2^-2/NO^-3的排出减少,光镜检查出现G2组近曲小管上皮细胞空泡变性,胞浆脱落,尤为皮髓交界处较为明显,肾小管管周细胞浸润,血管充血,G4组CsA肾脏扣害加重,G3组CsA肾脏病理改变减轻,组织定量分析支持镜下观察结果,结论：实验数据显示,L-arg对CsA所致毒性有拮抗作用,L－NAME对CsA肾毒性有协同促进效应。