CCK-8抑制LPS诱导大鼠肺间质巨噬细胞TNF-α转录及NF-κB活性

目的:观察硫酸化八肽胆囊收缩素(CCK-8)对体外脂多糖(LPS)诱导大鼠肺间质巨噬细胞(PIMs)TNF-α基因表达的影响,探讨核因子κB(NF-κB)是否参与这一过程,以揭示CCK-8抗炎作用的信号转导机制。方法:分离大鼠肺PIMs,经LPS、CCK-8、CCK受体拮抗剂丙谷胺及溶剂单独或联合应用孵育3h,用RT-PCR技术检测细胞TNF-αmRNA的表达,孵育1h,用电泳迁移率改变分析方法检测NF-κB活性,孵育30min,用Westernblot技术检测胞浆IκBα蛋白表达情况。结果:CCK-8(10^-8-10^-6mol·L^-1)明显降低了LPS诱导的TNF-αmRNA表达及NF-κB活性,增加了胞浆中IκBα蛋白水平,呈剂量依赖性,并可被丙谷胺所拮抗。结论:对LPS激活的肺PIMs,CCK-8通过抑制NF-κB活性而抑制其TNF-αmRNA表达,该作用由CCK受体介导,并与CCK-8减少IκBα蛋白降解有关,此为CCK-8抗炎作用的机制之一。     

肾上腺髓质素对豚鼠心室肌细胞L-型钙通道的作用及其信号转导机制

目的: 研究肾上腺髓质素( adrenomedullin, ADM)抑制豚鼠心室肌细胞L-型钙通道的信号转导机制。方法: 应用全细胞膜片钳技术,记录应用ADM(1-100 nmol·L^-1)前后L-型钙电流(I_Ca,L),以及分别记录应用ADM特异性受体拮抗剂ADM_22-52(100 nmol·L^-1)+ADM(100 nmol·L^-1)、蛋白激酶A (PKA) 特异性拮抗剂H-89(10 μmol·L^-1) + ADM(100 nmol·L^-1)、蛋白激酶C (PKC) 特异性拮抗剂PKC_19-36(10 μmol·L^-1)+ADM(100 nmol·L^-1)、PKC特异性激动剂PMA(1 μmol·L^-1)前后I_Ca,L。结果: ADM(1-100 nmol·L^-1)浓度依赖性地抑制豚鼠心室肌细胞I_Ca,L,并可被ADM_22-52(100 nmol·L^-1)完全阻断;H-89(10 μmol·L^-1)对ADM抑制I_Ca,L的作用无影响。PKC_19-36(10 μmol·L^-1)可完全阻断ADM 对I_Ca,L的抑制效应,且PMA(1 μmol·L^-1)可模拟ADM 对I_Ca,L的抑制效应。结论: ADM作用于特异性ADM受体可浓度依赖性地抑制豚鼠心室肌细胞I_Ca,L,此作用有可能与PKC激活相关。     

大鼠伏核、杏仁核、中脑导水管周围灰质内的CCK受体为CCK-B型受体:受体放射自显影分析

本工作用受体激动剂~(125)I-Bolton Hunter-CCK-8(~(125)I-BH-CCK)、CCK-A受体拮抗剂Devazepide、CCK-B受体拮抗剂L-365,260与脑组织切片共同孵育,以确定大鼠伏核、杏仁核、中脑导水管周围灰质等脑区内CCK受体的类型。结果显示:1μM未标记的CCK-8与~(125)I-BH-CCK及脑组织切片共同孵育,可完全竞争标记配体与受体的结合,说明这种结合是特异性的。30μM Devazepide可抑制脚间核处受体与标记配体的结合,但不能抑制伏核、杏仁核、中脑导水管周围灰质、大脑皮质及脊髓内受体与标记配体的结合;当剂量增大到90μM时,也只产生部分抑制。而用L-365,260只需90μM即可完全竞争伏核、杏仁核、中脑导水管周围灰质、大脑皮质及脊髓内受体与标记配体的结合。以上结果提示:脚间核部位的CCK受体为CCK-A受体;伏核、杏仁核、中脑导水管周围皮质、大脑皮质及脊髓内的CCK受体为CCK-B受体。     

CCK-8降低TNF-α诱导的大鼠RSC-364细胞增殖及p38 MAPK活性

目的观察硫酸化八肽胆囊收缩素(CCK-8)对TNF-α诱导大鼠成纤维样滑膜细胞株RSC-364细胞增殖及丝裂原活化蛋白激酶p38(p38 MAPK)活性的影响。方法采用噻唑蓝(MTT)比色法检测细胞增殖;Western blot技术检测p38 MAPK活性。结果TNF-α(50μg/L)孵育5 min,p38 MAPK磷酸化水平升高,15 min达高峰,2 h恢复基础水平;孵育15 min时,p38 MAPK磷酸化程度随其剂量(10、25、50μg/L)的增大而增加。CCK-8(10-10~10-6mol/L)剂量依赖性降低TNF-α诱导的细胞增殖及磷酸化p38 MAPK的激活,此作用可被CR1409和CR2945拮抗。SB203580(10μmol/L)可抑制TNF-α引起的细胞增殖。结论CCK-8通过降低p38 MAPK磷酸化水平而抑制TNF-α激活的RSC-364细胞增殖,该作用可能由CCK-A和CCK-B受体共同介导。     

CCK-8对内毒素血症小鼠腹腔巨噬细胞B7.1和B7.2表达及协同刺激功能的影响

目的： 探讨八肽胆囊收缩素（CCK-8）对内毒素血症小鼠腹腔巨噬细胞B7.1和B7.2表达及其协同刺激活性的影响。方法: 将BALB/c小鼠随机分组（n=4）,分别腹腔注射生理盐水（0.2-0.3 mL/mouse），LPS（100 μg/mouse）和/或CCK-8 (5 nmol/mouse)及CR1409（100 μg/mouse）、CR2945（100 μg/mouse）。12 h后收集并纯化腹腔巨噬细胞。采用流式细胞术分析细胞表面B7.1和B7.2含量的变化。用免疫磁珠从小鼠脾细胞分离CD4+T细胞，按4∶1数量比与上述处理的腹腔巨噬细胞共同体外培养，同时加入ConA 5 mg/L，采用［³H］掺入法测定CD4+T细胞增殖，反映巨噬细胞的协同刺激活性。结果: 整体应用CCK-8作用小鼠腹腔巨噬细胞，与对照组相比，CCK-8可上调静息小鼠腹腔巨噬细胞B7.2的表达，而对B7.1的表达则无影响；并且CCK-8使CD4+T细胞［³H］-TdR的掺入率升高，即促进其增殖，增强巨噬细胞的协同刺激活性。CCK-8降低LPS活化的内毒素血症小鼠腹腔巨噬细胞B7.1和B7.2的表达并且降低CD4+T细胞的［³H］-TdR掺入率，即抑制其增殖，抑制其协同刺激活性。CR1409及CR2945均能逆转CCK-8的上述作用，且CR1409的作用较CR2945更明显。结论: CCK-8通过上调巨噬细胞B7.2表达而增强其协同刺激活性；并且降低LPS活化的内毒素血症小鼠腹腔巨噬细胞B7.1和B7.2的表达，抑制其协同刺激活性。该作用由CCK1R及CCK2R共同介导，其中CCK1R起主要介导作用。     

八肽胆囊收缩素对脂多糖诱导小鼠分泌IL-12的影响及其机制研究

目的：观察八肽胆囊收缩素（CCK-8）对脂多糖诱导小鼠分泌IL-12的影响，探讨核因子-κB（NF-κB）和p38丝裂原活化蛋白激酶（p38 MAPK）的信号转导作用。方法：雌性BALB/c小鼠经LPS诱导后分别给予CCK及CCK-A、B受体拮抗剂。ELISA法检测小鼠血清及肺、脾组织中IL-12p40、p70的表达；Western blotting法检测肺脏、脾脏IκB、p38 MAPK的表达；EMSA法检测肺、脾组织中NF-κB/DNA的结合活性。结果：CCK-8进一步提高了LPS诱导的小鼠血清及肺、脾组织中IL-12p40、p70的表达；抑制IκB磷酸化和NF-κB/DNA结合活性；促进p38 MAPK磷酸化。而CCK-A受体拮抗剂（CR-1409）及CCK-B受体拮抗剂（CR-2945）部分逆转了CCK-8的效应。结论：CCK-8可促进LPS诱导小鼠分泌IL-12，p38 MAPK可能参与了其信号转导机制，而NF-κB途径可能并未参与CCK-8促IL-12分泌这一过程。     

CCK-8上调小鼠腹腔巨噬细胞B7.1和B7.2表达并增强其协同刺激活性

目的： 探讨八肽胆囊收缩素（CCK-8）对静息巨噬细胞B7.1和B7.2表达及其协同刺激功能的影响。方法：用CCK-8（10-12-10-6 mol/L）孵育小鼠腹腔巨噬细胞一定时间，采用流式细胞术分析细胞表面B7.1和B7.2含量的变化。用免疫磁珠从小鼠脾细胞分离CD4+T细胞，按4∶〖KG-*2〗1数量比与腹腔巨噬细胞（预先用CCK-8和/或抗B7.1抗体、抗B7.2抗体、CCK1R拮抗剂CR1409、CCK2R拮抗剂CR2945孵育24 h）共同体外培养，同时加入ConA 5 mg/L，采用［3H］掺入法测定CD4+T细胞增殖反映巨噬细胞的协同刺激活性。结果：CCK-8可上调静息巨噬细胞B7.1及B7.2的表达，并增强巨噬细胞的协同刺激活性。CCK-8的作用呈剂量依赖性，最大效应剂量是在10-9-10-7 mol/L之间。抗B7.2抗体可减轻CCK-8增强巨噬细胞协同刺激活性的作用，CR1409及CR2945均能逆转CCK-8的上述作用，且CR1409的作用较CR2945更明显。结论：CCK-8通过上调巨噬细胞B7.2表达而增强其协同刺激活性，该作用由CCK1R及CCK2R介导，其中CCK1R起主要介导作用。     

八肽胆囊收缩素逆转内毒素休克大鼠心功能降低的实验研究

目的: 观察八肽胆囊收缩素(CCK-8)改善内毒素休克(ES)大鼠心功能的变化,探讨CCK-8抗ES的作用及机制。方法: 实验分对照组、脂多糖(LPS)组、CCK组及CCK+LPS组;监测左室内收缩压(LVP)、左室收缩与舒张期内压变化的最大速率、心率(HR)和平均动脉压(MAP)的动态变化;分别测定2h血清、心肌组织中超氧化物歧化酶(SOD)活性、丙二醛(MDA)和一氧化氮(NO)含量的变化。结果: 静脉注射CCK-8(40μg·kg^-1),引起短时间心率减慢,轻度MAP、LVP和±LVdp/dt_max上升;静脉注时LPS(8mg·kg^-1),引起HR生快后慢双向改变MAP、LVP和±LVdp/dt_max快速持续下降;整体预先注射CCK-8,可明显缓解ES大鼠HR的快速变化,逆转MAP、LVP和±LVdp/dt_max下降,但未恢复至正常水平。CCK-8可提高ES大鼠血清、心肌组织中SOD活性,降低MDA和NO含量。结论: CCK-8可引起短时间心率减慢、轻度MAP上升和心肌收缩力增强;预先应用CCK-8可以减轻ES大鼠心肌氧化损伤,减少NO合成,恢复心肌收缩力,逆转心功能降低及顽固性低血压,是其发挥抗ES的重要机制之一。     

过氧化物酶体增殖物激活受体α在实验性大鼠脂肪肝中的表达

目的:研究过氧化物酶体增殖物激活受体α(PPARα)表达异常在脂肪肝发生中的作用。方法:采用小剂量CCl₄后肢皮下注射, 并高脂饮食复制大鼠脂肪肝动物模型, 检测肝脏甘油三酯(TG)、总胆固醇(TC)和游离脂肪酸(FFA)含量及血清谷丙转氨酶(ALT)、肿瘤坏死因子-α(TNF-α)和FFA含量, 并做病理切片, 测定肝脂变面积。提取肝脏总RNA, 运用半定量RT-PCR方法对肝脏PPARαmRNA的表达情况进行分析。结果:脂肪肝模型组大鼠肝脏TG、TC、FFA含量分别为(1.88±0.20)mmol·L^-1、(11.03±1.12)mmol·L^-1和(1260.38±151.27)μmol·L^-1, 正常对照组则为(0.53±0.10)mmol·L^-1、(1.25±0.25)mmol·L^-1和(334.30±27.09)μmol·L^-1(P＜0.01)。血清ALT、TNF-α和FFA含量亦明显高于对照组。肝脏PPARα的灰度比值:脂肪肝模型组0.41±0.28, 正常对照组1.41±0.29(P＜0.01)。结论:肝细胞中毒性脂肪肝时, 肝脏PPARα表达减少, 使肝中脂质的利用和脂肪酸的氧化均发生障碍, 导致肝脂蓄积。     

八肽胆囊收缩素抑制脂多糖诱导的大鼠肺间质巨噬细胞CD14的表达

目的:初步探讨八肽胆囊收缩素(CCK-8)对体外脂多糖(LPS)激活大鼠肺间质巨噬细胞(IM)的调节作用。方法:分离大鼠肺IM,经LPS、CCK-8、CCK受体拮抗剂丙谷胺及溶剂单独或共同孵育后,测定细胞CD14的表达及上清中TNF-α含量。 结果:LPS(1 mg/L)孵育12 h,肺IM mCD14表达上调,上清中sCD14及TNF-α含量均明显增加;CCK-8(10^-7-10^-6 mol/L)抑制了LPS的上述效应,且可被丙谷胺所拮抗。结论:CCK-8对LPS激活的肺IM的部分功能具有抑制性调节作用,该作用是由其受体介导的,可能是CCK-8减轻内毒素血症时肺组织炎性变化的重要机制之一。     

125I-(Thr34, Nle37)- CCK31–39 A Non Oxidizable Tracer for the Characterization of CCK Receptor on Pancreatic Acini and Radio-Immunoassay of C-Terminal CCK Peptides

A derivative of the C-terminal nonapeptide of CCK, namely (Thr₃₄, Nle₃₇) - CCK_31–39 was radio-iodinated by conjugation with ¹²⁵I-Bolton-Hunter reagent. The labelled peptide was purified by RP-HPLC on a C-18 column. Validation of the iodinated peptide was performed by measuring its biological integrity and by studying its binding characteristics on pancreatic acini. ¹²⁵I-(Thr, Nle)-CCK-9 present the same ability to stimulates amylase release than (Thr, Nle)- CCK-9 and CCK-8. Binding of the radio-ligand to CCK receptors is specific, reversible, saturable. Inhibition of the binding by CCK-related peptides correlates well their biological potencies. ¹²⁵I-(Thr, Nle)-CCK-9 is able to interact with high affinity CCK receptors. Furthermore, ¹²⁵I-(Thr, Nle)-CCK-9 is recognized by C-terminal CCK directed antibodies. This reliable tracer could be used as a replacement of CCK-8 since it is protected from risks of oxidation.     

125I-(Thr34, Nle37)- CCK31-39 a non oxidizable tracer for the characterization of CCK receptor on pancreatic acini and radio-immunoassay of C-terminal CCK peptides

A derivative of the C-terminal nonapeptide of CCK, namely (Thr34, Nle37) - CCK31-39 was radio-iodinated by conjugation with 125I-Bolton-Hunter reagent. The labelled peptide was purified by RP-HPLC on a C-18 column. Validation of the iodinated peptide was performed by measuring its biological integrity and by studying its binding characteristics on pancreatic acini. 125I-(Thr, Nle)-CCK-9 present the same ability to stimulates amylase release than (Thr, Nle)- CCK-9 and CCK-8. Binding of the radio-ligand to CCK receptors is specific, reversible, saturable. Inhibition of the binding by CCK-related peptides correlates well their biological potencies. 125I-(Thr, Nle)-CCK-9 is able to interact with high affinity CCK receptors. Furthermore, 125I-(Thr, Nle)-CCK-9 is recognized by C-terminal CCK directed antibodies. This reliable tracer could be used as a replacement of CCK-8 since it is protected from risks of oxidation.     

Lack of ghrelin secretion in response to fasting in cholecystokinin-A (-1), -B (-2) receptor-deficient mice

Cholecystokinin receptors (CCK-Rs) have been classified into two subtypes: CCK-AR (1R) and -BR (2R). We generated CCK-AR(-/-), CCK-BR(-/-), and CCK-AR(-/-)BR(-/-) mice and found that the gastric emptying of a liquid meal was increased in CCK-BR(-/-) and AR(-/-)BR(-/-) mice, compared with wild-type and CCK-AR(-/-) mice. Given that enhanced gastric emptying leads to eating, food intake after overnight fasting was examined, as was the effect of CCK-8S on food intake. Male mice 6-8 months of age were deprived of food for 16 h with free access to water, after which they were injected intraperitoneally (0.1 ml/mouse) with either vehicle or CCK-8 (0.3, 1.0, or 3.0 nmol/mouse), and their food intake was monitored for 4 h. CCK-8S inhibited food intake in wild-type and CCK-BR(-/-) mice, but not in CCK-AR(-/-) or AR(-/-)BR(-/-) mice. Unexpectedly, we observed a lower food intake in CCK-AR(-/-)BR (-/-) mice treated with vehicle than in mice of the other genotypes. To examine the mechanism of decrease in food intake in CCK-AR(-/-)BR(-/-) mice, the involvement of ghrelin was determined in wild-type and CCK-AR(-/-)BR(-/-) mice. Fasting plasma ghrelin levels were significantly lower in CCK-AR (-/-)BR(-/-) mice than in wild-type mice, and no increase in response to fasting was observed in CCK-AR(-/-)BR(-/-) mice. An administration of acyl-ghrelin produced a small increase in food intake in CCK-AR(-/-)BR(-/-) mice, but not to the levels of wild-type mice. In conclusion, CCK-AR(-/-)BR(-/-) mice showed lower food intake as well as lower response to exogenous ghrelin, and a lower plasma ghrelin level after fasting, though which receptor is more important is unknown.     

CCK-8抑制LPS作用下大鼠肺间质巨噬细胞NF-κB活性的cAMP-PKA通路研究

目的： 用cAMP激动剂forskolin和PKA抑制剂H-89，探讨八肽胆囊收缩素（CCK-8）抑制LPS作用下大鼠肺间质巨噬细胞（PIMs）核因子-κB （NF-κB）活性的cAMP-PKA信号通路机制。 方法： 分离纯化大鼠PIMs。用电泳迁移率改变分析（EMSA）法检测大鼠PIMs中NF-κB活性，用Western blotting分析IκB-α蛋白水平。 结果： 正常对照组大鼠PIMs核内未检测到与特异性寡核苷酸探针相结合的NF-κB，LPS组细胞内NF-κB活性明显高于正常对照组（P<0.01），胞浆中IκB-α水平显著低于正常对照组（P<0.01）。CCK组和Fsk组细胞内NF-κB活性和胞浆中IκB-α含量均无明显差异（P>0.05）。CCK+LPS组和Fsk+LPS组，细胞内NF-κB活性均低于LPS组（P<0.05），IκB-α含量均高于LPS组（P<0.01）。LPS+CCK+H-89组NF-κB活性高于CCK+LPS组（P<0.01），而IκB-α蛋白水平低于CCK+LPS组（P<0.01）。 结论： cAMP-PKA信号通路的活化可抑制LPS诱导的大鼠PIMs细胞内NF-κB活性升高和IκB-α蛋白水平的降低，CCK-8的抗炎作用是通过激活cAMP-PKA信号通路进而抑制NF-κB活性来实现的。     

p38 MAPK 和STAT3参与CCK-8抑制LPS诱导的大鼠促炎症细胞因子生成

 目的：观察八肽胆囊收缩素（CCK-8）是否改善脂多糖（LPS）引起的大鼠细胞因子的变化,并探讨p38丝裂原活化蛋白激酶(p38 MAPK)和信号转导子及转录激活子3(STAT3)的信号转导作用,以及CCK受体（CCK-R）的作用。方法：4组大鼠尾静脉分别注入生理盐水（对照）、LPS (8 mg/kg)、CCK-8(40 μg/kg)和CCK-8(40 μg/kg)+LPS (8 mg/kg), 酶联免疫吸附法（ELISA）检测血清、肺脏及脾脏中肿瘤坏死因子α（TNF-α）、白细胞介素1β（IL-1β）和IL-6的变化,Western blotting和免疫荧光双标激光共聚焦显微镜检测肺脏和脾脏磷酸化p38 MAPK和磷酸化STAT3的表达,RT-PCR检测脾脏CCK-R亚型的mRNA表达。结果：CCK-8可显著抑制LPS诱导的TNF-α、IL-1β和IL-6的增加。CCK-8可增加LPS诱导的大鼠肺脏和脾脏磷酸化p38 MAPK和磷酸化STAT3的表达。LPS有诱导CCK-AR及CCK-BR mRNA表达量增加的作用。结论：CCK-8对LPS刺激的大鼠促炎症细胞因子过量产生有抑制作用,p38 MAPK和STAT3可能参与了其信号转导机制。LPS刺激时,CCK-R受体发生正向调节,CCK-8有可能用于治疗全身性感染及其它的炎症性疾病。     

Brain-derived neurotrophic factor (BDNF) gene delivery into the CNS using bone marrow cells as vehicles in mice

This study investigated the behavioral mechanisms underlying the anxiogenic, or anxiolytic mediated effects of CCK(2) receptor mediated agonist (CCK-4) and antagonist drugs (LY225910, LY288513, CR2945) in PVG hooded and Sprague-Dawley (SD) rats using the elevated plus maze test apparatus. In addition, the effects of a CCK(1) antagonist (CR1409) were investigated for its possible mediation in anxiety behavior between PVG hooded and SD rats. PVG hooded rats treated with CCK-4, decreased the time spent in the open arm and increased the time spent in the closed arm and correspondingly showed increase in the number of entries in the open arms while the number of entries in closed arm was insignificant, whereas SD rats decreased the time spent in the closed arm, while other parameters remained insignificant. PVG hooded rats administered with various CCK(2) antagonists (LY225910, LY288513, and CR2945) significantly increased the time spent in the open arm and correspondingly decreased the time spent in the closed arm, while the number of entries in the open or closed arm was insignificant, in contrast, SD rats failed to show any reliable significance. PVG hooded rats administered with the CCK(1) antagonist (CR1409), failed to show any reliable significance, in contrast, SD rats significantly increased the time spent in the open arm. The strain differences observed in this study suggests that CCK plays mainly as a neuromodulator, in which the various CCK(2) antagonists may not affect baseline anxiety state, but instead they modulate heightened states of anxiety through differential effects of CCK(1)/CCK(2) receptors.