红杉黄酮通过下调PI3K/AKT信号通路抑制胃癌细胞增殖侵袭等干细胞特性

目的：探究红杉黄酮影响胃癌细胞的分子机制。方法：通过梯度浓度红杉黄酮处理胃癌细胞系AGS细胞，再使用PI3K/AKT信号通路激活剂对细胞进行诱导。采用CCK-8检测红杉黄酮对AGS细胞的最佳抑制浓度及时间，使用平板克隆、Transwell、细胞划痕实验检测细胞的增殖、迁移、侵袭能力变化。Western blot检测PI3K/AKT信号通路关键蛋白p-PI3K、PI3K、p-AKT、AKT。结果：红杉黄酮呈浓度依赖抑制AGS细胞，其半抑制浓度为0.5 mmol/L，最佳处理时间为48 h。红杉黄酮处理AGS细胞后，p-PI3K与p-AKT表达下调，AGS细胞增殖减少，迁移、侵袭能力降低；PI3K/AKT信号通路激活剂处理后，p-PI3K与p-AKT表达被部分逆转，增殖、迁移、侵袭能力降低也得到部分改善。结论：红杉黄酮通过失活PI3K/AKT信号通路抑制胃癌细胞增殖、迁移、侵袭等恶性行为。     

UNBS5162对脑胶质瘤细胞增殖和转移的抑制作用及机制

目的 通过体外实验,研究UNBS5162对脑胶质瘤细胞增殖和转移的抑制作用,并对其分子机制进行初步探究。方法 采用10 μmol/L UNBS5162处理脑胶质瘤细胞U251细胞为实验组,二甲基亚砜处理为对照组,分别应用CCK8实验、Transwell实验、流式细胞凋亡实验检测UNBS5162对U251细胞增殖、迁移和侵袭、凋亡的影响,应用蛋白免疫印迹法检测PI3K/AKT信号通路相关蛋白的表达水平。结果 实验组细胞增殖能力低于对照组（P<0.05）;并且其细胞迁移数和侵袭数均低于对照组;与对照组相比,实验组细胞凋亡率提高,且抗凋亡蛋白Bcl-2表达量降低、促凋亡蛋白Bax和Caspase-3表达量增加（P<0.05）。与对照组相比,PI3K/AKT信号通路的关键蛋白AKT和mTOR的磷酸化水平受到抑制,其下游p70S6K蛋白表达水平也相应降低（P<0.05）。结论 UNBS5162通过促进细胞凋亡对脑胶质瘤细胞的增殖和转移具有抑制作用,其机制与UNBS5162可以抑制PI3K/AKT信号通路的激活有一定相关性。     

小檗碱通过TGF-β/Smad通路抑制TGF-β1诱导的人肝癌HepG2细胞上皮间质转化的研究

目的探讨小檗碱(berberine)对转化生长因子-β1(transforming growth factor-β1,TGF-β1)诱导的人肝癌HepG2细胞上皮间质转化(epithelial-mesenchymal transition,EMT)的作用及其机制。方法MTT法检测小檗碱对HepG2细胞增殖活性;采用10 ng·L-1 TGF-β1诱导HepG2细胞EMT模型形成,并加入小檗碱处理;克隆形成实验、细胞划痕和Transwell小室实验分别检测HepG2细胞的克隆形成能力、迁移和侵袭能力;免疫荧光法检测EMT间质标志物Vimentin的表达;Western blot法检测EMT标志物蛋白(E-cadherin、N-cadherin、Snail)、基质金属蛋白酶(MMP-2)、TGF-β/Smad通路蛋白(Smad2、p-Smad2、Smad3、p-Smad3)的表达。结果小檗碱呈浓度时间依赖性抑制HepG2细胞活性;与TGF-β1组比较,小檗碱可以明显抑制HepG2细胞的克隆形成能力、迁移和侵袭能力;并且小檗碱可以抑制TGF-β1上调的E-cadherin蛋白表达,和TGF-β1下调的N-cadherin、Vimentin、Snail、MMP-2、p-Smad2、p-Smad3蛋白表达。结论小檗碱可能通过抑制TGF-β/Smad信号通路,干预TGF-β1诱导HepG2细胞的EMT进程,抑制HepG2细胞的迁移和侵袭能力。     

槟榔碱通过氧化应激介导的内皮间充质转化致HUVE细胞损伤的机制研究

目的 基于氧化应激介导的内皮间充质转化（EndMT）探讨槟榔碱（Arecoline）诱导人脐静脉内皮细胞（HUVEC）损伤的作用机制研究。方法 采用槟榔碱干预复制HUVECs损伤模型。实验设对照组、槟榔碱高剂量组和槟榔碱低剂量组。采用CCK-8检测不同浓度槟榔碱对HUVECs存活率的影响,细胞成像分析检测HUVECs形态学变化,采用MitoSOX探针检测线粒体活性氧（ROS）水平,采用免疫荧光及激光共聚焦检测氧化应激相关蛋白PGC-1α、Nrf2及EndMT相关蛋白E-cadherin、N-cadherin、Vimentin、SNAI1的表达情况,Western blotting检测氧化应激相关蛋白PGC-1α、Nrf2及EndMT相关蛋白N-cadherin、Vimentin的表达情况。结果 槟榔碱可以浓度依赖性抑制HUVECs活性,降低细胞存活率,诱导细胞形态结构发生变化,明显下调PGC-1α、Nrf2蛋白的表达,促进细胞线粒体释放ROS,同时显著下调细胞中E-cadherin蛋白的表达,上调N-cadherin、Vimentin和SNAI1蛋白的表达,最终诱导HUVECs发生EndMT,显著加重细胞损伤。结论 槟榔碱对HUVECs具有明显的损伤作用,可能是通过氧化应激介导的EndMT发挥作用,这可能是槟榔碱所致口腔黏膜下纤维化病变继而诱发口腔癌的重要病理机制。     

槲皮素抑制TGF-β1诱导SMMC-7721人肝癌细胞发生EMT的效果研究CSCD

目的旨在研究槲皮素抑制转化生长因子-β1(TGF-β1)诱导SMMC-7721人肝癌细胞发生上皮-间质转化(EMT)的效果。方法将肝癌细胞分为对照组(10 ng/ml TGF-β1)、低剂量组(50 nmol/l槲皮素+10 ng/ml TGF-β1)、高剂量组(10 ng/ml TGF-β1+100 nmol/l槲皮素),分别处理6 h,光学显微镜观察肝癌细胞形态学变化。6、12和24 h后,观察肝癌细胞迁移及侵袭能力。逆转录聚合酶链反应(RT-PCR)测定肝癌细胞E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)和波形蛋白(Vimentin)mRNA表达。Western blot法测定肝癌细胞E-cadherin、N-cadherin和Vimentin蛋白。结果经TGF-β1诱导后,肝癌细胞发生明显EMT。划痕实验结果显示,12和24 h时,高剂量组和低剂量组肝癌细胞迁移划痕空隙长度明显低于对照组(P<0.05)。侵袭实验中,与对照组比较,低和高剂量组每视野穿膜肝癌细胞数明显降低,且高剂量组穿膜高于低剂量组(P<0.05)。RT-PCR实验结果显示,对照组E-cadherin mRNA表达明显低于高剂量组和低剂量组(P<0.01),N-cadherin和Vimentin mRNA表达明显高于高剂量组和低剂量组(P<0.01)。低剂量E-cadherin mRNA表达明显低于高剂量组(P<0.01),N-cadherin和Vimentin mRNA表达明显高于高剂量组(P<0.01)。Western blot实验结果显示,对照组E-cadherin蛋白表达明显低于高剂量组和低剂量组(P<0.01),N-cadherin、Vimentin蛋白明显高于高剂量组和低剂量组(P<0.01)。高剂量组E-cadherin蛋白表达明显高于低剂量组(P<0.01),N-cadherin和Vimentin蛋白表达明显低于低剂量组(P<0.01)。结论槲皮素通过增加E-cadherin蛋白表达表达,降低N-cadherin、Vimentin蛋白表达,使得TGF-β1诱导的肝癌细胞EMT得到明显抑制。     

PD-L1反义寡核苷酸纳米颗粒对胃癌细胞侵袭和免疫因子分泌作用

摘要：目的:探讨细胞程序性死亡蛋白配体1(PD-L1)反义寡核苷酸纳米颗粒对胃癌细胞侵袭和免疫因子分泌的作用。方法:人胃癌细胞AGS分成对照(Control)组、聚氰基丙烯酸丁酷纳米粒(PBCA-NP)组、PD-L1正义寡核苷酸(SOND)组、PD-L1反义寡核苷酸(ASOND)组、PD-L1反义寡核苷酸纳米颗粒(ASOND-NP)组、ASOND-NP+胰岛素样生长因子1(IGF-1)组,采用Western Blot法检测PD-L1、磷酸化的磷脂酰肌醇3-激酶(p-PI3K)、PI3K、磷酸化的苏氨酸激酶(p-AKT)、AKT、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)、增殖细胞核抗原(PCNA)、基质金属蛋白酶2(MMP-2)、基质金属蛋白酶9(MMP-9)蛋白的表达,细胞计数试剂盒(CCK-8)检测细胞增殖活性,流式细胞术检测细胞凋亡率,Transwell小室检测细胞迁移和侵袭,ELISA法检测血管内皮生长因子(VEGF)、转化生长因子-β(TGF-β)、白细胞介素-6(IL-6)水平。结果:与Control组和SOND组比较,ASOND组胃癌细胞中PD-L1、p-PI3K/PI3K、p-AKT/AKT蛋白表达减少,细胞增殖活性降低,细胞凋亡率升高,Bax蛋白表达增多,Bcl-2、PCNA蛋白表达减少,细胞侵袭数目、迁移数目和MMP-2、MMP-9蛋白表达均减少,细胞分泌的VEGF、TGF-β、IL-6均减少(P<0.05);与PBCA-NP组和ASOND组比较,ASOND-NP组胃癌细胞中PD-L1、p-PI3K/PI3K、p-AKT/AKT蛋白表达减少,细胞增殖活性降低,细胞凋亡率升高,Bax蛋白表达增多,Bcl-2、PCNA蛋白表达减少,细胞侵袭数目、迁移数目和MMP-2、MMP-9蛋白表达均减少,细胞分泌的VEGF、TGF-β、IL-6均减少(P<0.05);与ASOND-NP组比较,ASOND-NP+IGF-1组胃癌细胞中p-PI3K/PI3K、p-AKT/AKT蛋白表达增多,细胞增殖活性升高,细胞凋亡率降低,Bax蛋白表达减少,Bcl-2、PCNA蛋白表达增多,细胞侵袭数目、迁移数目和MMP-2、MMP-9蛋白表达均增多,细胞分泌的VEGF、TGF-β、IL-6均增多(P<0.05)。结论:PD-L1反义寡核苷酸纳米颗粒通过抑制PI3K/AKT信号抑制胃癌细胞侵袭、迁移并减少免疫因子VEGF、TGF-β、IL-6分泌。     

AGGF1通过激活Wnt/β-catenin信号通路促进结直肠癌发生发展

目的 研究G补缀FHA域血管新生因子1（angiogenic factor with G-patch and FHA domain 1，AGGF1）调控Wnt/β-catenin信号通路对结直肠癌细胞（colorectal cancer，CRC）增殖、侵袭和上皮间质转化（epithelial mesenchymal transition，EMT）的可能机制。方法 通过裸鼠荷瘤免疫组化法检测AGGF1在正常组织和癌组织中的表达。qRT-PCR和Western blotting检测NCM460、SW620、HT29、HCT116、SW480中AGGF1的mRNA和蛋白表达水平。于HCT116细胞中过表达AGGF1，分为Vector组和AGGF1组；于SW620细胞中敲减AGGF1，分为shControl组和shAGGF1组。CCK-8法和克隆形成试验测定细胞活性和细胞克隆数目。划痕试验和Transwell试验检测细胞迁移和侵袭情况。免疫荧光检测细胞E-cadherin、N-cadherin的表达。Western blotting检测细胞E-cadherin、N-cadherin、AGGF1、β-catenin、糖原合酶激酶-3β （glycogen synthase kinase-3β，GSK-3β）、p-GSK-3β蛋白表达水平。结果 AGGF1蛋白表达在CRC组织中明显增高。AGGF1 mRNA和蛋白表达水平在HCT116细胞中最低，在SW620细胞中最高。CCK-8法、克隆形成试验、划痕试验和Transwell试验结果显示，在HCT116细胞中，与Vector组比较，AGGF1组48，72，96 h细胞活性、克隆细胞数目、相对迁移距离、侵袭细胞数显著增加（P<0.05或P<0.01）；而在SW620细胞中，与shControl组比较，shAGGF1组结果相反（P<0.05或P<0.01）。免疫荧光和Western blotting检测结果显示，与Vector组比较，AGGF1组E-cadherin荧光表达和蛋白表达水平降低（P<0.01），N-cadherin增强（P<0.05或P<0.01），同时上调AGGF1、β-catenin、p-GSK-3β/GSK-3β蛋白表达（P<0.01）；与shControl组比较，shAGGF1组E-cadherin荧光表达和蛋白表达水平显著升高（P<0.01），N-cadherin显著降低（P<0.05或P<0.01），同时下调AGGF1、β-catenin、p-GSK-3β/GSK-3β蛋白表达（P<0.05或P<0.01）。结论 AGGF1可通过激活Wnt/β-catenin信号通路异常表达，上调β-catenin、p-GSK-3β、N-cadherin表达，下调E-cadherin表达，促进CRC细胞增殖、迁移、侵袭和EMT，从而促进CRC发生发展。     

芹菜素对子宫内膜癌HEC-1-B细胞增殖和凋亡的影响及其机制研究

目的　研究芹菜素对子宫内膜癌细胞HEC-1-B增殖、侵袭、迁移、凋亡的影响及其作用机制。方法　取对数生长期的HEC-1-B细胞,加入0、20、40和80 μmol/L的芹菜素,采用CCK-8法检测培养24、48和72 h后细胞的光密度,计算增殖抑制率。流式细胞术检测细胞凋亡水平,Transwell实验检测细胞侵袭和迁移能力变化。Western blot检测凋亡相关蛋白Bax、Bcl-2以及磷脂酰肌醇3激酶（PI3K）、磷酸化PI3K（p-PI3K）、蛋白激酶B（AKT）和磷酸化AKT（p-AKT）的表达水平。结果　20~80 μmol/L范围内,随着芹菜素干预浓度的升高,HEC-1-B细胞的增殖明显受到抑制,细胞凋亡率升高,同时促凋亡蛋白Bax表达增高,抗凋亡蛋白Bcl-2表达下降。0、5、10和20 μmol/L范围内,随着芹菜素干预浓度的升高,HEC-1-B细胞侵袭和迁移能力下降。Western blot结果显示,40 μmol/L芹菜素能够下调PI3K/AKT通路蛋白p-PI3K和p-AKT的表达。结论　芹菜素能够抑制HEC-1-B细胞增殖、侵袭、迁移并促进其凋亡,其作用机制可能与PI3K/AKT信号通路有关。     

阿司匹林对鼻咽癌CNE-1、5-8F细胞增殖、迁移与侵袭作用机制研究

目的 探讨阿司匹林对人鼻咽癌CNE-1、5-8F细胞增殖、迁移与侵袭的影响和机制。方法 将人鼻咽癌CNE-1、5-8F细胞株分为对照组和阿司匹林（0.00、1.25、2.50、5.00、10.00mmol/L）处理组。噻唑蓝（MTT）法检测不同浓度阿司匹林作用24、48、72h后对CNE-1、5-8F细胞的增殖能力,以半数抑制浓度（IC₅₀）作为后续实验药物处理浓度。集落形成实验检测CNE-1和5-8F细胞增殖能力,Transwell实验检测CNE-1和5-8F细胞迁移及侵袭能力的变化,Western blotting法检测CNE-1和5-8F细胞中蛋白激酶B（Akt）、磷脂酰肌醇3-激酶（PI3K）、波形蛋白（Vimentin）、E-钙黏蛋白（E-cadherin）、Snail蛋白相对表达水平。结果 人鼻咽癌CNE-1、5-8F细胞分别经1.25、2.50、5.00、10.00mmol/L阿司匹林处理后,细胞增殖均受到不同程度抑制,且呈时间及浓度相关性,IC₅₀分别为3.3、2.7mmol/L。与对照组相比,经阿司匹林处理后,鼻咽癌CNE-1、5-8F细胞的细胞增殖和集落形成能力明显下降（P＜0.01）。与对照组相比,经阿司匹林处理后,划痕愈合率显著降低（P＜0.05）。Trasnwell迁移实验结果表明,与对照组相比,阿司匹林处理组鼻咽癌细胞CNE-1和5-8F 48h穿过小室的数目显著减少（P＜0.05、0.001）。与对照组相比,阿司匹林处理组CNE-1、5-8F细胞的E-cadherin蛋白表达显著增加（P＜0.05）,PI3K、Akt、Vimentin、Snail蛋白表达显著下降（P＜0.05、0.01）。结论 阿司匹林可通过上调E-cadherin蛋白的表达、抑制上皮间质转化进程从而抑制人鼻咽癌CNE-1、5-8F细胞迁移侵袭,同时下调PI3K、Akt、Vimentin、Snail蛋白的表达进而抑制CNE-1、5-8F细胞增殖、迁移和侵袭能力。     

异氟醚对小儿神经母细胞瘤术后肿瘤复发及转移的影响

目的 探究异氟醚对小儿神经母细胞瘤术后肿瘤复发和转移的影响。方法 采用ELISA法检测经异氟醚麻醉前后神经母细胞瘤患者血清中上皮间质转化(epithelial mesenchymal transition, EMT)相关蛋白E-钙粘蛋白(E-cadherin)、波形蛋白(vimentin)和血管内皮因子(vascular endothelial growth factor, VEGF)的表达水平；采用CCK-8、Transwell和Western blotting法检测经异氟醚或同时经PI3K抑制剂LY294002处理的SH-SY5Y细胞增殖、迁移、侵袭及EMT和PI3K/Akt通路相关蛋白、VEGF和HIF-1α的表达水平。结果 在经异氟醚麻醉的神经母细胞瘤患者血清中E-cadherin表达下调，Vimentin和VEGF表达上调。异氟醚能够促进SH-SY5Y细胞增殖、迁移、侵袭和EMT,并上调p-PI3K、p-Akt和HIF-1α的表达水平；异氟醚通过激活PI3K/Akt通路上调HIF-1α的表达促进SH-SY5Y细胞生物学行为，且能够被PI3K抑制剂LY294002阻断。结论 异...     

Analgesia induced by brief footshock is inhibited by 5-hydroxytryptamine but unaffected by antagonists of 5-hydroxytryptamine or by naloxone

Exposure to footshock (1 mA) for 30 sec induced a marked analgesia that was enhanced by pretreatment with the 5HT synthesis inhibitor, p-chlorophenylalanine, and attenuated by the 5HT releasing drugs p-chloroamphetamine and fenfluramine, by the 5HT re-uptake inhibitor, fluoxetine and by the 5HT agonists, 5-methoxy-N,N-dimethyltryptamine and MK212. However, agonists, quipazine and trifluoromethylphenylpiperazine, with greated reported affinities for 5HT binding sites on rat brain membranes than MK212 were without effect as were the antagonists metergoline, methysergide, cyproheptadine, mianserine and methiothepin. The specific opioid antagonist naloxone was also without effect. The results in general indicate that analgesia induced by brief footshock (1 mA, 30 sec) is inversely related to 5HT availability but thereis little evidence of involvement of known 5HT receptors.     

Synergism by caffeine and by cocaine of the motor control deficit produced by midazolam

To evaluate the effects of caffeine and cocaine on the impairment of discriminative motor control produced by midazolam, rats were trained to hold a force transducer operated with a paw so that it remained between upper and lower limits of a force band for a continuous 1.5-s period to deliver each food pellet. Acute doses of 3 mg/kg midazolam SC impaired motor performance. Except for one animal, caffeine (10-40 mg/kg IP) had little or no effect on performance, while cocaine (3.75-22.5 mg/kg IP) produced dose-related impairment. When each dose of caffeine was combined with 3 mg/kg midazolam, a marked synergism in motor performance impairment occurred. Cocaine plus midazolam produced mainly an additive synergism. The conspicuous synergistic action of caffeine on the motor control deficit produced by midazolam contrasts with the typical antagonism found between the benzodiazepines and methylxanthines when performance is evaluated by psychomotor tests not requiring fine motor control.     

Interference by cephalosporins with creatinine measurement by desk-top analyzers

Summary We have carried out a study to evaluate the interference by cephalosporins with the measurement of creatinine by desk-top analyzers. The cephalosporins evaluated at concentrations of 0–250 mg/l were cefazolin sodium, cefoxitin sodium, cefotaxime sodium, and ceftazidime pentahydrate. The instruments evaluated were DT60 (Kodak, Rochester, USA), Seralyzer (Ames Division, Miles Laboratories, IN, USA), and Vision (Abbott Labs, Chicago, USA). All studies were done in plasma.None of the cephalosporins showed any interference with the DT60 analyzer. With the Vision and Seralyzer no interference was seen with cefotaxime or cefazolin. With cefazolin an increase of 10–20 µmol/l creatinine was seen for every 20 mg/l of drug; with cefoxitin there was an increase of 50–80 µmol/l of creatinine for every 100 mg/l of drug.Erroneous creatinine values may be found in patients taking cefazolin and cefoxitin and may lead to inappropriate clinical management.     

Deamination of beta-phenylethylamine by monoamine oxidase--inhibition by imipramine

The oxidative deamination of tyramine (Tyr), 5-hydroxytryptamine (5-HT), and β-phenylethylamine (PEA) by mitochondrial preparations of rabbit lung and brain was inhibited by imipramine. This tricyclic iminodibenzyl antidepressant drug was most effective in decreasing the deamination of PEA: at 1 × 10^?4M imipramine, deamination of PEA, Tyr and 5-HT was inhibited by approximately 70, 45 and 45 per cent, respectively, when either lung or brain mitochondrial monoamine oxidase (MAO) preparations were used. Imipramine-induced inhibition of MAO was shown to be of a mixed type based on Lineweaver-Burk plots, but was found to be completely reversible. The desmcthyl and didesmethyl derivatives of imipramine were equally as effective as the parent drug in inhibiting the deamination of PEA, whereas the N-oxide analog of imipramine was less effective as an inhibitor of this reaction. These results support the premise that the action of imipramine as a clinically effective antidepressive agent may be related to its inhibitory effect on the specific form of MAO which deaminates PEA.     

Augmentation by serrapeptase of tissue permeation by cefotiam

Cefotiam (CTM) is a new cephalosporin with a broad spectrum of activity against both Gram-positive and Gram-negative microorganisms. Cephalosporins are widely used for prophylaxis of infections in patients undergoing thoracotomy. Augmentation by serrapeptase on tissue permeation of CTM was examined in 35 thoracotomy patients with lung cancer. The subjects were divided into two groups according to the method of the administration of CTM. Group I consisted of 17 subjects, each of whom received a single dose of 2 g of CTM alone by an instillation for 30 minutes. Group II consisted of 18 subjects, each of whom received a combination of CTM and serrapeptase; serrapeptase was given 2 tablets (10 mg) each time for three times/day until the day before surgery, and then CTM was administered by the same procedure. The following results were obtained: Individual difference was observed for the permeation of CTM into tissues. Pathologic differences also affected the permeation. Nevertheless, the CTM levels in pulmonary tissues reached about a half of those in the blood in both the single dose group and the combination group, hence sufficient concentrations exceeding MIC80 for main microorganisms that caused infections in the lung were obtained. The concentrations of CTM in inflammatory tissues have showed lower levels than those of normal tissues in both CTM single dose and the combination groups. Decrease of blood flow volume may have contributed to the reduction in levels of CTM in the inflammatory tissues. The ratio of the concentration of the drug in pulmonary tissues to that in the blood was 29.1 +/- 2.5% in the single dose group, and 44.2 +/- 6.0% in the combination group, the latter showing quite a significant increase (P less than 0.05). Combined administrations of CTM and serrapeptase deserves more trials in the case when surgical treatments of the lung are performed. An antiinflammatory effect of serrapeptase in the respiratory system is expected, and in addition, the combined use of CTM and serrapeptase should stimulate permeation of the antibiotic into tissues.     

Antagonism of morphine by beta-melanocyte-stimulating hormone and by tetracosactin

Using the decerebrate—spinal Lloyd preparation morphine depressed evoked mono- and polysynaptic reflex activity, β-melanocyte-stimulating hormone enhanced monosynaptic reflex activity, and tetracosactin had no effect. When morphine injection was preceded either by β-melanocyte-stimulating hormone or by tetracosactin a statistically significant depression was not observed. The stimulant actions of β-melanocyte-stimulating hormone did not appear to account for its capacity to antagonize morphine. The fall of blood pressure which follows the administration of morphine in this preparation was not antagonized by the prior administration of either polypeptide.     

Immunomodulation by non-absorbable antibiotics given by the intragastric route

To test the role of bacterial fractions released from intestinal flora during immunomodulation by antimicrobial agents, BALB/c mice were treated with the non-absorbable antibiotics polymyxin B or teicoplanin by the intragastric route. The composition of faecal microbiota and the capacity of spleen cells to proliferate in response to B-cell and T-cell mitogens were assessed at several times during the treatment. Both antibiotics lowered the count of some bacteria of the intestinal flora and induced significant modifications in spleen cell ability to proliferate in response to mitogens. Thus, the active fractions released from intestinal bacteria during antibiotic treatments may be able to induce immunomodulating effects.