Melanin‐concentrating hormone‐1 receptor binding activity of pheophorbides isolated from morus alba leaves

The time‐resolved fluorescence technique based on melanin‐concentrating hormone (MCH) receptor subtype‐1 (MCH‐1 receptor) binding assay was adopted to carry out a bioassay‐guided fractionation of the methanol extract of Morus alba leaves. This fractionation and purification led to the isolation of two compounds identified as pheophorbide a methyl ester and 13²(S)‐hydroxypheophorbide a methyl ester. These active pheophorbides exhibited potent inhibitory activity in binding of europium‐labeled MCH to the human recombinant MCH‐1 receptor (IC₅₀ value; 4.03 and 0.33 ?M, respectively). Besides binding activity, the pheophorbides inhibited MCH‐mediated extracellular signal‐regulated kinase (ERK) phosphorylation in Chinese hamster ovary cells expressing human MCH‐1 receptor. These results suggest that pheophorbide a methyl ester and 13²(S)‐hydroxypheophorbide a methyl ester act as modulators of MCH‐1 receptor and MCH‐mediated ERK signaling. Copyright © 2009 John Wiley & Sons, Ltd.     

中药制剂赋肝能对小鼠实验性肝损伤的保护作用

 目的 观察中药制剂赋肝能(由植物鹅绒萎陵菜 Potentilla anserinal.分离提取而得的主要活性成分,简称FGN),对小鼠实验性肝损伤的保护作用,评价赋肝能的退黄降酶作用效果。方法 采用化学毒物四氯化碳(CCl₄),α萘异硫氰酸酯(ANIT)致小鼠肝脏损伤,测定其生化指标并观察病理组织学改变。结果 赋肝能0.165,0.0825 g·kg^-1均能显著降低CCl₄肝损伤所致的小鼠血清丙氨酸转氨酶(ALT)升高(P＜0.01)及ANTT肝损伤所致的小鼠血清总胆红素(SB)升高(P＜0.01);赋肝能0.04125 g·kg^-1对上述指标没有影响。结论 上述结果表明,赋肝能对小鼠实验性肝损伤具有明显的保护作用。     

左旋多巴甲酯对剥夺性弱视猫视网膜c-fos表达的影响

目的:研究左旋多巴甲酯(LDME)对剥夺性弱视猫视网膜细胞凋亡情况以及c-fos表达及其分布的特点,并探讨其作用机制.方法:健康2周龄幼猫30只随机分成6组:模型对照组及正常对照组,左旋多巴阳性对照组,LDME低、中、高剂量组,每组5只.除了正常组,各组幼猫于4周龄时单纯缝合左眼建立剥夺性弱视,12周后打开缝合眼并开始给药,每天灌胃LDME 20,40,80 mg· kg-1,阳性组为左旋多巴40 mg· kg-1,正常组与模型组为等量生理盐水,持续30 d.TUNEL法检测视网膜细胞的凋亡情况,经原位杂交技术、免疫组化检测视网膜中c-fos mRNA和c-fos蛋白的表达.结果:与模型对照组比较,LDME明显减少弱视猫视网膜组织的细胞凋亡指数(P ＜0.05或P＜0.01),显著上调c-fos mRNA在视网膜中的表达(P＜0.05或P＜0.01),同时增加c-fos免疫阳性细胞数量(P＜0.05或P＜0.01).结论:左旋多巴甲酯有效地保护剥夺性弱视造成的视网膜损伤,其机制可能与抑制细胞凋亡以及促进c-fos表达有关.     

Xanthine Oxidase Inhibitory Activity of Flavonoids and Tannins from Hexachlamys edulis (Myrtaceae)

The acetone-water extract of Hexachlamys edulis (Myrtaceae) inhibited the enzyme xanthine oxidase (XO) in vitro . Bioassay-guided isolation led to the gallic acid ester in 2″ of myricitrin (desmanthin-1), (-)-epigallocatechin-3-O-gallate (EGG) and pentagalloylglucose as the main XO inhibitors of H. edulis . Desmanthin-1 and EGG were mixed-type inhibitors of XO with K _i values of 1.6×10⁻⁴ M and 1.8×10⁻⁴ M , respectively. Pentagalloylglucose was an uncompetitive XO inhibitor with a K _ESI of 6.7×10⁻⁶M . From the active n -butanol soluble part of the aqueous acetone extract of H. edulis , several flavonoids were isolated. The flavonoids were mainly myricetin-3-O-monoglycosides with the quercetin glycoside avicularin as a minor compound displaying a weak inhibitory activity towards XO.     

Evaluation of the antiulcerogenic activity profile of a flavonol diglucoside from Equisetum palustre L.

Ethnopharmacological relevance

The aerial parts of Equisetum palustre L. are used to treat peptic ulcer disease in Turkey. In a previous study, a flavonol diglucoside i.e., kaempferol 3-O-1″-β-d-glucopyranosyl-3-O-1″′-β-d-glucopyranoside (KGG) was isolated as the major antiulcerogenic constituent from the plant.

Aim of the study

The present study was undertaken to evaluate the antiulcer activity profile of KGG using various in vivo experimental ulcer models as well as by assessing gastric biochemical parameters.

Material and methods

KGG was obtained from the ethanol extract of the aerial parts of the plant by successive chromatographical methods. The activity profile of the compound was investigated using several ulcerogenesis models such as indomethacin-, indomethacin plus HCl/EtOH-, cysteamine-, serotonin-, N^G-nitro-l-arginine methyl ester plus EtOH-, diethyldithiocarbamate-, N-ethylmaleimide plus EtOH-, water immersion and restraint stress-, pyloric ligation-induced ulcers. In addition, effects of KGG on the biochemical parameters of gastric juice; i.e., inhibition of titratable gastric acidity, acid output, gastric pH, gastric secretion volume and peptic activity were studied.

Results

KGG exerted statistically significant gastroprotective activity against indomethacin-, indomethacin plus HCl/EtOH- and N-ethylmaleimide plus EtOH-induced ulcerogenesis. Moreover, KGG demonstrated weak activity against N^G-nitro-l-arginine methyl ester plus EtOH, water immersion and immobilization-induced stress, pyloric ligation-induced and diethyldithiocarbamate-induced gastric ulcer models, and also it was ineffective in the prevention of ulcers induced by serotonin and cysteamine. On the other hand, among the gastric biochemical parameters studied, KGG was only found to increase the gastric acid pH from 2.03 to 3.35.

Conclusion

Results of this investigation have clearly demonstrated that KGG was found to improve the cytoprotective mechanisms of the gastric mucosa. On the other hand, a weak activity profile was observed on the parameters affecting the gastric acidity (water immersion and restraint-induced-, pyloric ligation-induced-ulcerogenesis and titratable acidity).     

LC/MSn鉴定丁香酚布洛芬酯在大鼠尿中的主要代谢产物

 目的研究鉴定丁香酚布洛芬酯在大鼠体内的代谢行为。方法选择健康Wistar大鼠3只单剂量20mg·kg^-1尾静脉给药丁香酚布洛芬酯后,收集0～12h尿样。将尿样经SPEC₁₈固相萃取柱纯化后,采用LC/MSn方法对尿中的待测的代谢产物进行选择离子监测(SIM)和多级全扫描质谱分析(MSn)。结果在尿中首次检测到丁香酚布洛芬酯的7种代谢产物,其中包括1种Ⅰ相代谢产物和6种Ⅱ相代谢产物。结论丁香酚布洛芬酯在大鼠体内主要先水解成丁香酚和布洛芬,经进一步代谢与葡萄糖醛酸结合。     

基于叶酸受体的靶向性钆造影剂的制备及弛豫性能的研究

 目的制备基于叶酸受体的靶向大分子磁共振造影剂——叶酸-壳聚糖-(Gd-DTPA)_n,并研究其体外弛豫性能。方法在EDC的催化下,将壳聚糖与DTPA反应,制得壳聚糖-DTPA偶联物,然后将该偶联物与叶酸活性酯反应所得产物与GdCl₃螯合得到叶酸-壳聚糖-(Gd-DTPA)_n。在磁共振仪上测定配合物的体外弛豫时间T₁,并分析其弛豫性能R₁。结果制得的叶酸-壳聚糖-(Gd-DTPA)_n配合物中叶酸的偶联率约为4,Gd-DTPA与壳聚糖的偶联率随着EDC的加入量增大而增大,体外弛豫性能R1约为6.2×10^-3 L·mmol^-1·ms^-1,比小分子Gd-DTPA的弛豫性能提高了2.3倍左右。结论成功地制备了叶酸介导的高弛豫效能的靶向性磁共振造影剂。     

Berberine promotes the viability of random skin flaps via the PI3K/Akt/eNOS signaling pathway

Random skin flaps are often used in reconstruction operations. However, flap necrosis is still a common postoperative complication. Here, we investigated whether berberine (C₂₀H₁₉NO₅, BBR), a drug with antioxidant activity, improves the survival rate of random flaps. Fifty-four rats were divided into three groups: control, BBR and BBR + _L-NAME groups (_L-NAME, _L-N^G-Nitro-arginine methyl ester). The survival condition and the percentage of survival area of the flaps were evaluated on the seventh day after surgery. After animals were sacrificed, angiogenesis, apoptosis, oxidative stress and inflammation levels were assessed by histological and protein analyses. Our findings suggest that berberine promotes flap survival. The level of angiogenesis increased; the levels of oxidative stress, inflammation and apoptosis decreased; the levels of phosphoinositide 3-kinase (PI3K), phospho-Akt (p-Akt) and phospho-endothelial nitric oxide synthase (p-eNOS) increased in the flap tissue; and _L-NAME reversed the effects of berberine on random skin flaps. Statistical analysis showed that the BBR group results differed significantly from those of the control and the BBR + _L-NAME groups (p < .05). Our results confirm that berberine is an effective drug for significantly improving the survival rate of random skin flaps by promoting angiogenesis, inhibiting inflammation, attenuating oxidative stress, and reducing apoptosis through the PI3K/Akt/eNOS signaling pathway.     

铁箍散藤茎的化学成分研究

目的:研究铁箍散 Schisandra propinqua 藤茎的化学成分及药理活性。方法:利用多种色谱技术进行分离纯化,根据化合物理化性质和光谱分析鉴定化合物的结构。用四唑盐(MTT)比色试验测定浸膏及化合物对15%FBS诱导的血管平滑肌细胞增殖的影响。结果:从铁箍散的石油醚部分分离得到5个化合物,分别鉴定为:galgravin(1),veraguensin(2),2,3-二羟基丙基十八酸酯(3),2,3-二羟基丙基十六酸酯(4),2,3-二羟基丙基二十四酸酯(5)。结论:化合物1~5均为首次从该植物中分离得到,化合物1,2,5对体外血清诱导的平滑肌细胞增殖表现出了一定的抑制作用。     

超临界CO2萃取山茱萸成分研究

目的 :对山茱萸超临界CO₂流体萃取物进行研究。方法 :萃取条件为 :压力 15MPa,温度40℃ ,时间2h ,液态CO₂ 流量 22.0kg·h^-1,,采用GC-MS技术分析山茱萸CO₂ 超临界萃取物的化学组成。结果 :超临界CO₂流体萃取法得率为 2.42%。鉴定了其中 31种成分 ,并用面积归一化法测定其相对含量。结论 :超临界CO₂ 流体萃取物主要成分有1,2-苯二甲酸二 (1-丁基-2-异丁基 )酯 ,异丙基十四 [烷 ]酸酯等。     

在体单向肠灌流模型考察灯盏乙素乙酯的肠吸收特性

目的:分析灯盏乙素乙酯(scutellarin ethyl ester,DZY-02)在大鼠小肠各肠段的吸收机制。方法:采用大鼠在体单向肠灌流模型,运用HPLC测定肠灌流液中DZY-02含量,考察3个剂量组DZY-02在大鼠十二指肠、空肠、回肠的吸收情况,分析P-糖蛋白(P-glycoprotein,P-gp)和乳腺癌耐药蛋白(breast cancer resistance protein,BCRP)抑制剂对DZY-02吸收的影响。结果:DZY-02在低、中、高质量浓度下,各小肠段的吸收速率常数和有效渗透系数(Peff)均无显著性差异,Peff均0.2×10-4cm·s-1。在相同质量浓度下,DZY-02在不同肠段的吸收速率常数均无显著性差异;P-gp和BCRP抑制剂均对DZY-02吸收无影响。结论:DZY-02在大鼠肠道内为高渗透性药物,在小肠内均有吸收,且无特定的吸收窗。在一定质量浓度范围内,DZY-02在大鼠肠道内吸收无高浓度饱和抑制现象,推断DZY-02在大鼠肠道内的吸收机制可能为被动扩散。DZY-02不是P-gp和BCRP蛋白的底物。     

左旋多巴甲酯对斜视性弱视猫视皮层神经生长因子表达的影响

目的:观察左旋多巴甲酯对幼猫斜视性弱视的治疗作用及其对视皮层17区神经生长因子(NGF)表达的影响。方法:正常幼猫30只随机分成6组:正常对照组、模型对照组、阳性对照组及左旋多巴甲酯低、中、高剂量组每组5只,于4周龄时行眼外直肌切除术造成人工斜视(正常对照组除外),经图形视觉诱发电位(PVEP)确定形成弱视后,ig左旋多巴甲酯20,40,80 mg.kg-1,阳性对照组ig左旋多巴40 mg.kg-1,正常对照组及模型组均ig等量生理盐水。观察PVEP的变化及应用免疫组织化学法测定各组视皮层17区NGF的差异。结果:模型对照组与正常对照组相比,PVEP的P100波潜时延迟,波幅降低,免疫阳性细胞数量明显减少(P<0.05);治疗组和模型对照组相比,P100波潜时缩短,波幅增大,免疫阳性细胞增加(P<0.05)。结论:敏感期内斜视性弱视幼猫视皮层17区NGF的表达减弱;左旋多巴甲酯干预治疗后,NGF表达明显增加,弱视眼PVEP明显改善;左旋多巴甲酯能促进实验幼猫弱视眼的视功能改善。     

生淫羊藿与炙淫羊藿对肾阳虚证水肿模型大鼠的影响

目的:研究生品与炮制后的淫羊藿对肾阳虚水肿模型大鼠的作用,为阐明炮制前后淫羊藿治疗肾阳虚水肿的作用机制。方法:用氢化可的松联合盐酸多柔比星复制肾阳虚水肿大鼠模型,即造模第1,8天分别尾静脉注射盐酸多柔比星(3. 5 mg·kg-1),与此同时,连续14 d腹腔注射强化可的松注射液(3. 75 mg·kg-1·d-1)进行造模,造模结束后将造模成功的大鼠分为模型组,生淫羊藿组(204. 86 mg·kg-1),炙淫羊藿组(204. 86 mg·kg-1),同时设立正常组,各组大鼠分别给予相应药物(10 m L·kg-1),正常组和模型组给予同体积蒸馏水,连续灌胃14 d。给药结束后,大鼠代谢笼法测24 h尿量,采用紫外分光光度法测定尿液中尿蛋白的含量;血清中指标的测定,采用全自动生化分析仪测血浆白蛋白(ALB),血清总蛋白(TP),血清肌酐(SCr),血清尿素氮(BUN)含量;采用酶联免疫测定(ELISA)检测环磷酸腺苷(c AMP),环磷酸鸟苷(c GMP),三碘甲状腺原氨酸(T3),甲状腺素(T4),雌二醇(E2),睾酮(T)指标含量,取肾脏适量做苏木素-伊红(HE)染色病理切片。结果:与正常组比较,模型组大鼠从外观指标,生化指标,病理切片指标上均证明模型组大鼠处于肾阳虚水肿状态(P 0. 05,P 0. 01);与模型组比较,生淫羊藿给药组与炙淫羊藿给药组对肾阳虚水肿的外观指标与病理切片指标均有回调作用,且在生化指标上,生、炙淫羊藿给药组均能回调尿量,尿蛋白,SCr,BUN,c AMP/c GMP,E2,T指标(P 0. 05,P 0. 01),但是回调强度有所不同。生淫羊藿给药组极显著性回调尿量,尿蛋白,SCr,BUN(P 0. 01);炙淫羊藿给药组极显著性回调c AMP/c GMP,E2,T(P 0. 01)。此外,生淫羊藿给药组还可以回调ALB,TP(P 0. 05,P 0. 01),而炙淫羊藿给药组对这2个指标没有回调作用,炙淫羊藿给药组可以回调T3,T4,肛温(P 0. 05,P 0. 01),而生淫羊藿给药组对这2个指标没有回调作用。结论:生淫羊藿与炙淫羊藿给药组均可以治疗肾阳虚水肿,机制可能与改善阿霉素所致的肾小球足细胞损伤有关。生淫羊藿与炙淫羊藿治疗肾阳虚水肿侧重点有所不同,生淫羊藿性寒,更侧重于加强肾阳虚水肿大鼠的肾脏排泄功能来治疗肾阳虚水肿。炙淫羊藿经羊油炮制后产生了淫羊藿苷等物质,药性由寒转温,偏重改善肾阳虚水肿大鼠肾阳虚状态来治疗肾阳虚水肿。     

Molecular mechanism of Chuanxiong Rhizoma in treating coronary artery diseases

ObjectiveMost of the studies on the herb Chuanxiong Rhizoma (CR) have focused on the l-arginine-nitric oxide (NO) pathway, but the nitrate-nitrite-NO (NO₃⁻–NO₂⁻–NO) pathway was rarely investigated. Therefore, the aim of this study was to evaluate the effects and mechanisms of action of CR in coronary artery disease (CAD).MethodsThe NO₃⁻, NO₂⁻ and NO levels were examined in the NO₃⁻–NO₂⁻–NO pathway. High-performance ion chromatography was used to quantify NO₃⁻ and NO₂⁻ levels. Then, NO was quantified using a multifunctional enzyme marker with a fluorescent probe. The tension of aortic rings was measured using a multi myograph system.ResultsHigh content of NO₃⁻ and low content of NO₂⁻ was found in CR, and which could potently convert NO₃⁻ to NO₂⁻ in the presence of endogenous reductase enzyme. Incubating human coronary artery endothelial cells (HCAECs) with CR-containing serum showed that CR significantly decreased the NO₃⁻ content and increased the levels of NO₂⁻ and NO in the cells under hypoxic conditions. In addition, CR significantly relaxed isolated aortic rings when the l-arginine –NO pathway was blocked. The optimal concentration of CR for relaxation was 200 mg/mL.ConclusionCR supplements large amounts of NO in cells and vessels to achieve relaxation via the NO₃⁻–NO₂⁻–NO pathway, thereby making up for the deficiency caused by the lack of NO after the l-arginine-NO pathway is suppressed. This study also supports the potential use of a traditional Chinese herb for future drug development.     

2小时环孢素A血药浓度是预测移植肾排异反应的敏感指标

 目的探讨环孢素A服药后2 h的血药浓度(c₂)与临床排异及生化指标的关系。方法 选择本院58例初次肾移植术患者,在术后0-3个月内同时监测全血环孢素A的c₀和c₂各170次,并对手术前后常规生化指标进行统计学分析。结果环孢素A在非排异组和排异组的c₀与c₂分别是(371±127),(263±88)ng·mL^-1(P>0.05)和(1102±422),(727±304)ng·mL^-1(P<0.05)。结论肾移植术后c₂监测是预测和判断急性排异反应的敏感指标,术后尽早使c₂水平达到1000-14 00 ng·mL^-1,临床效果比较理想。     

白藜芦醇对阿霉素致心衰大鼠心肌损伤的保护作用

目的：观察白藜芦醇(resveratrol,RES)对阿霉素(adriamycin,ADR)致急性心衰大鼠心功能的保护作用。方法：取成年雄性SD大鼠30只,随机分为5组：空白对照组(NC),ADR模型组、RES低剂量(RES_L)+ADR组,RES高剂量(RES_H)+ADR组及RES组。RES_L+ADR,RES_H+ADR组及RES组,分别给予RES 30,120,120 mg·kg^-1·d^-1腹腔注射,1次/d,连续3 d；其他两组腹腔注射等量生理盐水。第4天除NC组及RES组外,其余3组一次性腹腔注射ADR10 mg·kg^-1,制备急性心衰大鼠模型。24 h后,光镜观察心肌细胞形态及生化指标的变化。结果：光镜观察显示,RES+ADR组心肌细胞的变性坏死明显减轻。ADR模型组丙二醛(MDA)、一氧化氮(NO)、一氧化氮合酶(NOS)显著增加,超氧化物岐化酶(SOD)显著减少(P<0.05)。与ADR模型组相比,RES_L+ADR,RES_H+ADR组的MDA,NO,NOS显著减少,SOD增加(P<0.05),并呈剂量依赖性。结论：RES可显著减轻ADR对心肌的毒性作用,其作用与抗氧化和减少NO的产生有关。     

酮洛芬异丙酯在HaCaT细胞中的代谢

 目的研究酮洛芬异丙酯在HaCaT细胞中的代谢作用，为探讨HaCaT细胞作为研究酯类前体药物的皮肤代谢模型提供实验依据。方法采用含不同浓度酮洛芬异丙酯的人角质形成细胞无血清培养基进行HaCaT细胞培养，或将不同量酮洛芬异丙酯加入HaCaT细胞的PBS匀浆中进行37℃温孵实验，通过高效液相色谱法分别在不同时间测定细胞培养液和细胞匀浆中酮洛芬异丙酯及酮洛芬的浓度。结果酮洛芬异丙酯在HaCaT细胞培养和匀浆中能被水解成酮洛芬。酮洛芬的形成速率与酮洛芬异丙酯初始浓度的大小有关，在低浓度时随酮洛芬异丙酯初始浓度增大而增加。细胞培养中，加入1.478 9，4.735 3，9.034 1，11.851 1μmol·L^-1的酮洛芬异丙酯对细胞活性影响不大，酮洛芬的形成速率分别是0.069 6，0.272 2，0.886 0，0.675 1μmol·L^-1·h^-1。细胞匀浆中，酮洛芬异丙酯的初始浓度是7.457 3，12.678 7，24.784 5，44.694 3 μmol·L^-1，相应的酮洛芬形成速率分别为0.134 7，0.278 2，0.473 5，0.608 9μmol·L^-1·h^-1。结论HaCaT细胞作为一种常用的角质形成细胞系细胞，可用于研究酯类前体药物的皮肤代谢。     

麻杏石甘汤对枸橼酸致豚鼠咳嗽的影响

目的:探讨麻杏石甘汤防治枸橼酸所致豚鼠咳嗽的作用及初步机制。方法:豚鼠随机分成正常组、模型组、可待因组、麻杏石甘汤低、中、高剂量组(2.3,6.5,14.6 g.kg-1),分别连续ig给药7 d,最后1次给药后1 h,采用枸椽酸致豚鼠咳嗽模型,以生物信息采集系统记录咳嗽信号、录音和人工计数等方法统计咳嗽次数和咳嗽潜伏期,对支气管进行病理切片观察,并检测血清过氧化氢酶活力和过氧化氢的含量。结果:模型组咳嗽次数为(53.6±10.7)次,支气管组织有炎性细胞浸润现象,血清过氧化氢含量增加(71.3±18.8)mol.L-1。而麻杏石甘汤高、中、低剂量组均能明显降低枸橼酸所致咳嗽次数,分别为(30.9±9.9),(39.8±8.6),(36.4±2.8)次(P<0.05),减少支气管黏膜下层细胞炎性细胞浸润,降低血清中过氧化氢含量,分别为(60.6±7.3),(44.7±10.1),(33.8±7.5)mol.L-1(P<0.05),但只有高剂量组才延长咳嗽潜伏期(P<0.05)。结论:麻杏石甘汤能防治枸橼酸所致豚鼠咳嗽,引起过氧化氢的改变可能是其作用机制之一。     

甘宝胶囊对小鼠急性肝损伤的保护作用

目的:研究甘宝胶囊对四氯化碳(CCl4)、乙醇、扑热息痛所致小鼠急性肝损伤的保护作用。方法:取昆明种小鼠60只,随机分为6组:空白对照组,肝损伤模型对照组,甘宝胶囊0.125,0.25,0.5 g·kg-1剂量组,联苯双酯阳性对照组0.2 g·kg-1;ig给药,每日1次,至设定日期末分别用CCl4、乙醇、扑热息痛造成急性肝损伤模型。比色法检测血清中的丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)和碱性磷酸酶(AKP)的水平,同时测定肝脏系数,此外CCl4造模组测溶血素、脾脏和胸腺系数。结果:甘宝胶囊高、中剂量组能明显降低由CCl4、乙醇、扑热息痛致肝损伤模型的ALT,AST,肝脏系数(P<0.05或P<0.01)。高剂量组能显著降低扑热息痛造模小鼠AKP的活性(P<0.05),并显著升高CCl4造模小鼠的溶血素含量,降低胸腺系数及脾脏系数(P<0.05或P<0.01)。结论:甘宝胶囊对四氯化碳、乙醇、扑热息痛致肝损伤具有明显的保护作用。     

Vasorelaxant effects of Cerebralcare Granule are mediated by NO/cGMP pathway,potassium channel opening and calcium channel blockade in isolated rat thoracic aorta

Ethnopharmacological relevance

Cerebralcare Granule (CG), one of the famous classical recipes in traditional Chinese medicine, is developed from the “Decoction of Four Drugs”. It has been used for treatment of cerebrovascular related diseases, such as hypertension. It is well known that vasodilatation plays a very important role in hypertensive. Despite the popular medicinal use of CG, little data was available to its activity and mechanism involved in vasodilatation. Therefore, we aimed to investigate the vasorelaxant effects of CG on isolated rat thoracic aorta so as to assess some of the possible mechanisms. The present study was performed to examine the vasodilative activity of CG and its mechanisms in isolated rat thoracic aorta.

Materials and methods

CG was studied on isolated rat thoracic aorta in vitro, including endothelium-intact and endothelium-denuded aortic rings. In present study, specific inhibitors including NO synthase inhibitor N^G-nitro-l-arginine methyl ester (l-NAME), cyclooxygenase (COX) inhibitor indomethacin (INDO), non-selective K⁺ channel inhibitor tetraethylammonium chloride (TEA), K_ir channel inhibitor BaCl₂, K_ATP channel inhibitor Glibenclamide (Gli) and cholinergic receptor antagonist atropine were used, they were added 20 min before NE contraction and then added CG-induced vasodilation.

Results

Removal of endothelium or pretreatment of aortic rings (intact endothelium) with l-NAME (0.1 mM) or INDO (0.01 mM) significantly blocked the CG induced relaxation. Pretreatment with the non-selective K⁺ channel inhibitor TEA (1 mM), or the K_ir channel inhibitor BaCl₂ (0.1 mM), neither of them had no influence on the CG-induced response (p>0.05). However, pretreatment with the K_ATP channel inhibitor Gli (0.01 mM) produced significant inhibition on the CG-induced response (p<0.01). Besides, CG also inhibited the contraction triggered by NE in endothelium-denuded rings in Ca²⁺-free medium. CG (0.4, 0.8 and 3.2 mg/mL) produced rightward parallel displacement of CaCl₂ curves and reduced the maximum contraction induced by 30 mM CaCl₂ to 31.1±9.3%, 18.8±6.9% and 9.4±4.5%, respectively. The relaxation, induced by CG on endothelium-intact rat aortic rings pre-contracted with NE, was significantly attenuated in the presence of atropine (EC₅₀=3.7 mg/mL, p<0.01).

Conclusions

Our results suggest that CG induces relaxation in rat aortic rings through an endothelium-dependent pathway mediated by NO/cGMP pathway and an endothelium-independent pathway involving blockade of Ca²⁺ channels, inhibition of Ca²⁺ mobilization from intracellular stores, opening of K_ATP channel. In addition, the muscarinic receptor stimulation is also one of the vasorelaxant mechanisms.