CCK-8及其受体拮抗剂对吗啡戒断大鼠额叶皮质、尾壳核、海马μ阿片受体的影响

目的通过观察CCK-8及其受体拮抗剂对吗啡戒断大鼠额叶皮质、尾壳核、海马μ阿片受体的影响,初步探讨CCK-8对吗啡戒断症状的影响及其受体机制。方法建立大鼠吗啡慢性依赖及纳络酮催促戒断模型,观察CCK-8及CCK1受体拮抗剂L-364,718、CCK2受体拮抗剂LY-288,513慢性干预对戒断症状的影响,并采用放射配基结合法测定额叶皮质、尾壳核、海马μ阿片受体的结合活性,即受体数量(Bmax)及结合力(Kd)。结果①给予吗啡前腹腔注射CCK-8及CCK受体拮抗剂慢性干预均可减轻吗啡戒断症状;②慢性吗啡作用后,额叶皮质和海马μ阿片受体数量及结合力下降,而尾壳核μ阿片受体数量无变化,仅结合力降低;戒断后,额叶皮质、尾壳核μ阿片受体数量及结合力升高,而海马μ阿片受体数量无变化,仅结合力升高;③CCK-8及其受体拮抗剂慢性干预后,使吗啡戒断大鼠尾壳核μ阿片受体结合力降低、海马μ阿片受体数量增加,但是对额叶皮质μ阿片受体的结合活性无影响。结论 CCK-8及其受体拮抗剂可通过调节μ阿片受体减轻吗啡戒断症状,并具有脑区特异性。     

八肽胆囊收缩素及其受体拮抗剂对吗啡戒断大鼠脑内CaMK Ⅱ蛋白表达的影响

目的观察八肽胆囊收缩素(CCK-8)、CCK-1受体拮抗剂L-364,718及CCK-2受体拮抗剂LY-288,513对吗啡戒断大鼠额叶皮质、海马、纹状体细胞内钙/钙调蛋白依赖性的蛋白激酶Ⅱ(CaMKⅡ)表达的影响。方法建立吗啡依赖及纳洛酮催促戒断大鼠模型,观察CCK-8、L-364,718及LY-288,513对吗啡依赖大鼠戒断症状的影响;采用Western blot方法检测上述脑区CaMKⅡ蛋白表达的变化。结果①CCK-8、L-364,718及LY-288,513能明显改善吗啡依赖大鼠戒断症状的发生;②与盐水对照组相比,吗啡依赖组大鼠额叶皮质、海马、纹状体细胞内CaM KⅡ蛋白表达明显升高;纳洛酮催促戒断后上述脑区CaM KⅡ蛋白表达较吗啡依赖组均明显降低;③CCK-8、L-364,718及LY-288,513均使吗啡戒断大鼠额叶皮质、海马及纹状体内CaMKⅡ蛋白表达升高。结论 CaMKⅡ参与了吗啡依赖及戒断的形成,CCK-8及其受体拮抗剂抑制吗啡依赖大鼠戒断反应的机制可能与其对相关脑区CaMKⅡ蛋白表达的调节有关。     

八肽胆囊收缩素及其受体拮抗剂对吗啡戒断大鼠脑内[Ca~(2+)]_i和CaM活性的影响

目的观察八肽胆囊收缩素(CCK-8)及其受体拮抗剂对吗啡戒断大鼠皮质、海马、纹状体神经细胞内[Ca2+]i和CaM活性的影响。方法剂量递增法(10⁵0 mg·kg-1)连续5 d皮下注射吗啡建立吗啡依赖模型,并给予腹腔注射纳洛酮(5 mg·kg-1)催促戒断,采用流式细胞术检测大鼠皮质、海马、纹状体[Ca2+]i和CaM活性的变化。结果 (1)与盐水对照组相比,吗啡依赖组大鼠皮质、海马、纹状体内[Ca2+]i和CaM活性均明显升高;纳洛酮催促戒断后[Ca2+]i和CaM活性较吗啡依赖组均明显降低;(2)CCK-8及CCK-1受体拮抗剂L-364,718、CCK-2受体拮抗剂LY-288,513均使吗啡戒断大鼠海马和纹状体内[Ca2+]i和CaM活性明显升高,但皮质内[Ca2+]i和CaM活性无明显变化。结论 CCK-8及其受体拮抗剂对吗啡依赖大鼠戒断反应的作用可能与其对相关脑区神经细胞内[Ca2+]i和CaM活性的调节有关。     

侧脑室注射东莨菪碱对吗啡依赖大鼠戒断反应的抑制作用

目的 观察非选择性毒蕈碱（M）受体拮抗剂东莨菪碱、选择性M1受体拮抗剂哌拉唑嗪以及选择性M2受体拮抗剂美索四氨对吗啡戒断反应的影响。方法 采用吗啡依赖大鼠模型侧脑室注射上述药物,并用腹腔注射纳洛酮诱发戒断反应,记录60min内戒断症状。结果 侧脑室注射东莨菪碱（25,50μg)、派拉唑嗪（20μg)和美索四氨（25μg)可明显抑制由纳洛酮诱发戒断反应,东莨菪碱减轻吗啡戒断症状呈明显量效关系。结论 侧脑室注射东莨菪碱能减轻吗啡戒断反应,提示中枢胆碱能神经毒碱（M）受体在吗啡依赖和耐受过程中起重要作用。     

CCK-8与内源性阿片系统在吗啡依赖中的相互作用

目的通过观察不同剂量的CCK-8对吗啡依赖SH-SY5Y细胞模型内源性阿片系统的影响,初步探讨CCK-8与内源性阿片系统在吗啡依赖过程的相互作用及其机制。方法建立吗啡慢性依赖SH-SY5Y细胞模型,应用放射配基结合技术观察μ阿片受体(MOR)结合特征,应用Real-Time PCR技术检测前脑啡肽原(PENK)、前阿黑皮质素原(POMC)基因的表达,并观察CCK-8对上述指标的影响。结果①10μmol·L-1吗啡作用于全反式维甲酸(RA)分化6d的SH-SY5Y细胞48h,成功建立了慢性吗啡依赖模型;②CCK-8可剂量依赖性地抑制MOR的结合,并且此抑制作用可被CCK1及CCK2受体拮抗剂(L-364,718,LY-288,513)翻转;③10-7、10-6mol·L-1CCK-8使PENK、POMC的表达较正常组分别增加(5.81±0.84)、(7.26±1.55)倍和(4.55±0.73)、(5.16±0.82)倍。吗啡依赖后,PENK、POMC表达较正常组下降(0.43±0.10)倍和(0.37±0.07)倍,10-8、10-7、10-6mol·L-1CCK-8使下调的PENK、POMC表达增加,PENK与正常组的相对表达值为(0.63±0.10)、(0.86±0.21)、(1.17±0.19),POMC与正常组的相对表达值为(0.46±0.10)、(0.60±0.11)、(0.96±0.11)。10-10、10-9mol·L-1CCK-8对PENK、POMC表达无影响。结论低剂量(10-10、10-9mol·L-1)CCK-8可通过激活CCK受体抑制MOR的结合力,对PENK、POMC的表达无影响;高剂量(10-8～10-6mol·L-1)的CCK-8可使PENK、POMC基因表达增加,促进内源性阿片肽的生成,并可改善吗啡依赖后内源性阿片系统的失衡。     

5-HT_(1A)受体激动剂乌拉地尔对吗啡依赖大鼠戒断反应的抑制作用

目的··：观察５－ＨＴ１Ａ受体激动剂乌拉地尔（ｕｒａｐｉｄｉｌ）和８－ＯＨ－ＤＰＡＴ及阿片μ受体激动剂美沙酮（ｍｅｔｈａｄｏｎｅ）对吗啡戒断反应的影响。方法··：采用吗啡依赖大鼠模型侧脑室注射上述药物,并用腹腔注射纳洛酮诱发戒断反应,记录戒断症状。结果··：侧脑室注射乌拉地尔可明显抑制纳洛酮诱发的吗啡躯体戒断反应,并呈量效关系。乌拉地尔抑制吗啡戒断反应的作用与８－ＯＨ－ＤＰＡＴ的作用一致。此效应与美沙酮的作用相比也基本相同。结论··：乌拉地尔通过激活５－ＨＴ１Ａ受体可以抑制吗啡戒断反应。     

吗啡依赖大鼠脊髓和脑干μ受体和κ受体mRNA表达的研究

目的 观察吗啡依赖戒断时大鼠脊髓和脑干μ受体和Κ受体mRNA表达以及毒蕈碱受体拮抗剂、NMDA受体拮抗剂和NOS抑制剂对些基因表达的影响。方法 用逆转录聚合酶链反应（RT－PCR）,以β-actin mRNA为内标检测μ受体和Κ受体mRNA的表达水平。结果 吗啡依赖大鼠脊髓和脑干μ受体mRNA表达明显升高,纳洛酮激发大鼠戒断反应1h后μ受体基因表达降低,4h后接近正常组,而脊髓和脑干Κ受体基因的变化与μ受体基因表达趋势相反。鞘内注射PKA抑制剂Rp-cAMPs和蛋白磷酸酶抑制剂calyculinA可以明显减少脊髓和脑干中μ受体和Κ受体基因表达,而PKA激活剂Sp-cAMPs则无明显影响;经NOS抑制剂l-N-硝基精氨酸甲酯（l-NAME)处理后,脊髓μ受体和Κ受体基因表达明显减少,经毒蕈碱（M）受体拮抗剂甲基东莨菪碱处理后,脊髓μ受体和脑干Κ受体基因表达也明显减少,而脊髓Κ受体和脑干μ受体基因表达变化不明显;经NMDA拮抗剂MK801和M1受体拮抗剂哌拉唑嗪处理后,脊髓和脑干μ受体和Κ受体基因表达较戒断1h组无明显差异。脊髓和脑干中β-actin基因表达各处理组之间没有差别。结论 吗啡依赖和戒断动物脊髓和脑干中μ受体和Κ受体基因表达发生改变,M受体拮抗剂和NOS抑制剂在吗啡戒断反应时减少μ受体和Κ受体基因表达可能是它们有效控制吗啡戒断症状的机制之一。     

5-HT1A受体激动剂乌拉地尔对吗啡依赖大鼠戒断反应的抑制作用

目的··：观察５－ＨＴ１Ａ受体激动剂乌拉地尔（ｕｒａｐｉｄｉｌ）和８－ＯＨ－ＤＰＡＴ及阿片μ受体激动剂美沙酮（ｍｅｔｈａｄｏｎｅ）对吗啡戒断反应的影响。方法··：采用吗啡依赖大鼠模型侧脑室注射上述药物,并用腹腔注射纳洛酮诱发戒断反应,记录戒断症状。结果··：侧脑室注射乌拉地尔可明显抑制纳洛酮诱发的吗啡躯体戒断反应,并呈量效关系。乌拉地尔抑制吗啡戒断反应的作用与８－ＯＨ－ＤＰＡＴ的作用一致。此效应与美沙酮的作用相比也基本相同。结论··：乌拉地尔通过激活５－ＨＴ１Ａ受体可以抑制吗啡戒断反应。     

吗啡对原代培养大鼠皮质神经元神经甾体水平的影响

目的探讨吗啡慢性处理对大鼠大脑皮质神经元合成释放神经甾体水平的影响及其机制。方法建立原代培养大鼠大脑皮质神经元吗啡依赖样模型,固相萃取结合高效液相色谱-质谱联用法测定细胞培养液中神经甾体水平;免疫印迹法检测神经元中p-CREB水平。结果与盐水对照组相比,吗啡(1μmol.L-1)处理使PREG和DS的水平降低(P<0.01);μ-受体激动剂DAMGO使PREG、DS和PS水平下降,AP水平增高;与吗啡单独处理组相比,μ-阿片受体拮抗剂CTAP与吗啡联合处理使PREG增加(P<0.01)。与盐水对照组相比,吗啡或DAMGO慢性处理均可增加神经元内p-CREB的水平(P<0.01);与吗啡处理组相比,CTAP抑制吗啡诱导的p-CREB的增加。结论μ-阿片受体参与了介导吗啡慢性处理对皮质神经元神经甾体合成释放的影响;神经元内p-CREB水平的变化反映了吗啡引起的神经元适应性改变,提示神经甾体水平的变化可能与吗啡依赖有关。     

拮抗触液核P物质对吗啡戒断大鼠行为学的影响

目的观察P物质(substance P,SP)在吗啡戒断大鼠触液核内的表达及拮抗触液核内SP对吗啡戒断行为学的影响,探讨触液核内SP在吗啡戒断中的作用。方法 SPF级SD♂大鼠2组,吗啡戒断-人工脑脊液组(A组)和吗啡戒断-SP抑制剂组(B组);两组均采用剂量递增法腹腔注射盐酸吗啡,建立大鼠吗啡依赖模型,在d4上午侧脑室注射霍乱毒素亚单位B-辣根过氧化物酶复合物(CB-HRP)逆行追踪触液神经元;B组d5上午在立体定位仪下侧脑室注射SP拮抗剂(D-Pro2、D-Phe7、D-Trp9)-SP,A组注射人工脑脊液作为对照组;d6上午腹腔注射纳络酮(5mg·kg-1)建立吗啡戒断模型;并进行戒断行为学评分、记录戒断总评分(total withdrawal scores,TWS),免疫荧光结合激光共聚焦显微镜观察SP的表达。结果 A组大鼠触液核内SP表达增加,B组显示,拮抗触液核内SP可减弱吗啡戒断样症状;两组TWS相比较,A组高于B组(P<0.01)。结论抑制触液核内SP能够减轻吗啡戒断症状,本研究首次证实触液核SP表达参与了吗啡躯体依赖的发展与纳洛酮药物催促戒断,这将有助于利用药理学手段干预阿片依赖寻找新方法。     

八肽胆囊收缩素对[~3H]埃托啡与大鼠脑阿片受体结合的抑制作用

本实验观察了CCK—8对[~3H]Et与大鼠脑阿片受体结合的影响.含硫CCK—8能抑制[~3H]Et与高亲和位点的结合,使K_D值增大(P<0.001),B_(max)减小(P<0.01),在10 fmol/L～Lμmol/L范围内呈量效关系.但对低亲和位点的结合没有影响.无硫CCK—8仅对[~3H]Et高亲和位点的K_D值有较小程度的增大(P<0.05),不影响B_(max)值.CCK—8(10 nmol/L)抑制[~3H]Et与阿片受体结合的作用能被CCK受体拮抗剂谷丙酰胺(1μmol/L)所阻断.结果提示,CCK—8可能通过激活CCK受体发挥对阿片受体的抑制作用。     

On the Mechanism(s) of Cholecystokinin (CCK): Receptor Stimulation Attenuates Morphine Dependence in Mice

Abstract: In the present study, effect of cholecystokinin (CCK) agonists and on dependence to morphine in mice has been investigated. The influence of dopaminergic, adrenergic, cholinergic and serotonergic on attenuation of naloxone-induced jumping in morphine-dependent mice by CCK agonists were also considered. Mice were treated subcutaneously with morphine (50, 50 and 75 mg/kg) three times daily (10 a.m. 1 p.m. and 4 p.m.) for 3 days, and a last dose of morphine (50 mg/kg) was administered on the 4th day. Withdrawal syndrome (jumping) was precipitated by naloxone (5 mg/kg) which was administered intraperitoneally 2 hr after the last dose of morphine. To study effects of CCK receptor agonists, 10 injection of morphine (3 administrations each day) for dependence and a dose of 5 mg/kg of naloxone for withdrawal induction were employed. The CCK agonists CCK-8 (0.001- 0.1 mg/kg), unsulfated CCK-8 (CCK-8U; 0.001-0.1 mg/kg) and caerulein (0.00001-0.01 mg/kg) were able to prevent withdrawal signs precipitated by naloxone (5 mg/kg). Sulpiride and pimozide increased response induced by CCK-8 agonists. The dopamine antagonists also attenuates jumping by themselves. SCH 23390 did not alter the CCK-8 effect, but decreased the jumping by itself. Phenoxybenzamine, propranolol, methysergide and atropine did not change the caerulein effect significantly. However, single administration of atropine increased and methysergide decreased jumping. It is concluded that CCK mechanism(s) may be involved in morphine dependence, and dopaminergic mechanism(s) may interact with CCK in attenuation of naloxone-induced jumping.     

Cholecystokinin and morphine-induced hypothermia.

The effects of cholecystokinin-8 sulfate (CCK-8), cholecystokinin-8 unsulfate (CCK-8U), cholecystokinin-4 (CCK-4), caerulein and morphine on mice core body temperature have been studied in the present work. Subcutaneous injection of different doses of caerulein (0.05, 0.1 and 0.5 mg/kg), CCK-8 (0.05, 0.1 and 0.25 mg/kg) and morphine (10, 20 and 30 mg/kg) induced hypothermia. CCK-8U and CCK-4 did not elicit any response. The hypothermic response induced by caerulein, a CCK-related decapeptide but not morphine was decreased by selective CCK(A) receptor antagonist MK-329. However, the hypothermia induced by morphine but not caerulein was reduced by opioid antagonist naloxone. When morphine plus caerulein was administered a higher hypothermia was induced. Pretreatment of animals with L-365 260, a selective CCK(B) receptor antagonist did not alter the hypothermia induced by the drugs. The response induced by combination of the both drugs was decreased by MK-329. Administration of CCK antagonists MK-329 and L-365 260 to mice did not exert any effect on temperature. It is concluded that the CCK(A) receptor mechanism may be involved in the hypothermic effect of CCK agonists or morphine, while opioid receptor mechanism is not involved in CCK receptor agonists' response.     

Peripheral participation of cholecystokinin in the morphine-induced peripheral antinociceptive effect in non-diabetic and diabetic rats

The effects of cholecystokinin (CCK-8) and the CCK receptor antagonist proglumide, on antinociception induced by local peripheral (subcutaneous) injected morphine in non-diabetic (ND) and streptozotocin-induced diabetic (D) rats, were examined by means of the formalin test. Morphine induced dose-dependent antinociception both in ND and D rats. However, in D rats, antinociceptive morphine potency was about twofold less than in ND rats. Pre-treatment with CCK-8 abolished the antinociceptive effect of morphine in a dose-dependent manner in both groups of rats. Additionally, proglumide enhanced the antinociceptive effect induced by all doses of morphine tested. Both CCK-8 and proglumide had no effect on flinching behaviour when given alone to ND rats. Unlike ND rats, in D rats proglumide produced dose-dependent antinociception and CCK-8 enhanced formalin-evoked flinches, as observed during the second phase of the test. In conclusion, our data show a decrease in peripheral antinociceptive potency of morphine when diabetes was present. Additionally, peripheral CCK plays an antagonic role to the peripheral antinociceptive effect of morphine, additional to the well known CCK/morphine interaction at spinal and supraspinal level.     

Effects of cholecystokinin octapeptide on the exocrine pancreas in a new rat model of type 2 diabetes

We investigated the effects of increasing concentrations of cholecystokinin octapeptide (CCK-8) on the exocrine pancreas of a new model of type 2 diabetic rats due to the partial protection exerted by nicotinamide against the beta-cytotoxic effect of streptozotocin. CCK-8, administered for 8 successive days, exerted a biphasic action on the growth of the pancreas in non-diabetic and type 2 diabetic rats; however, the latter were less sensitive to CCK-8. Similar results were obtained in vitro by measuring the uptake of 5-bromo-2'-deoxyuridine (BrdU) in cultured isolated acinar cells. This effect was completely blocked by 3S(-)(N'-2,3-dihydro-1-methyl-2-oxo5-phenyl-1H-1,4-benzo-diazepin-3-yl)-1H-indole-2-carboxamide (L 364,718; a CCK(1) receptor antagonist) but not by (3R)-3[N'-(3-methylphenyl)ureido]-1,3-dihydro-1-methyl-5-phenyl-2H1,4-benzo-diazepin-2-one (L 365,260; a CCK(2) receptor antagonist), suggesting a direct effect via CCK(1) receptors. Binding studies showed that these effects were mediated by a single class of low-affinity CCK(1) receptors in diabetic rats and two classes of CCK-8 binding sites (with high and low affinity) in non-diabetic rats. Thus, in our new type 2 diabetes model, the loss of sensitivity of the pancreas to CCK-8 could be attributed to the loss of CCK(1) receptors of high affinity.     

毒蕈碱和NMDA受体拮抗剂对吗啡依赖大鼠脊髓和脑干前脑啡肽原和前强啡肽原mRNA表达的影响

目的　观察毒蕈碱 (M)受体拮抗剂对吗啡依赖大鼠脊髓和脑干前脑啡肽原 ( preproenkephalin ,PPE)和前强啡肽原 ( preprodynorphin ,PPD)mRNA表达的影响。 方法　本文利用逆转录聚合酶链反应 (RT PCR) ,以 β actinmRNA为内标检测了PPE和PPDmRNA。结果　吗啡依赖大鼠脊髓和脑干PPE基因表达和正常大鼠相比都略有增加 ,吗啡依赖大鼠注射纳洛酮激发戒断反应后 ,脊髓PPE基因表达增加 ,而脑干中变化不明显。吗啡依赖大鼠脊髓和脑干PPD基因表达都低于正常大鼠组 ,吗啡戒断反应时脊髓PPD基因表达在 1h变化不明显 ,2h时增加到峰值 ,4h时仍高于依赖组 ,而脑干强啡肽基因表达在 1h、2h和 4h时都明显减少。经M受体拮抗剂甲基东莨菪碱和M1拮抗剂 pirenzepine处理后大鼠脊髓和脑干PPE和PPD基因表达较戒断 1h组有不同程度的增加 ;经NMDA受体拮抗剂MK 80 1处理后 ,脊髓和脑干中PPE基因较戒断组 1h无明显差异 ,脊髓和脑干PPD基因表达较戒断组明显增加 ;而经NOS抑制剂L N 硝基精氨酸甲酯 (L NAME)处理后大鼠脊髓和脑干PPE基因表达较戒断 1h组有不同程度的增加 ,脊髓和脑干PPD基因表达变化不明显。脊髓和脑干中 β actin基因表达在各处理组之间没有差别。结论　M受体拮抗剂、NMDA受体拮抗剂和NOS抑制剂在吗啡戒断反应时增加     

Conditioned place preference: no tolerance to the rewarding properties of morphine

The effect of repeated morphine administration on conditioned place preference (CPP) using a novel treatment schedule, i.e., drug treatment was always contingent with the conditioned environmental stimuli, was investigated. We also examined whether changes in the μ- and κ-opioid receptor binding occurred in the brain of morphine-treated animals. Intraperitoneal (i.p.) administration of morphine (2 and 10 mg/kg) induced a place preference after 8 daily conditioning trials (4 morphine injections on alternate trials), the level of preference being the same with the two doses of the opiate. No change in place preference was observed in the morphine-treated rats at 2 mg/kg, when animals were further trained up to a total of 32 conditioning trials (16 morphine injections). Conversely, after 20 conditioning trials (10 morphine injections), a stronger CPP response developed in the morphine-treated rats at 10 mg/kg. Signs of morphine withdrawal were never detected in morphine-treated rats during the experiment. Loss of body weight (index of opiate dependence) was not observed either 24 h or 48 h after the last morphine administration. μ- and κ-opioid receptor density and affinity were not affected by repeated morphine administrations at either dose. The results demonstrate that no tolerance develops to the rewarding properties of morphine. Indeed, a sensitisation effect may occur at increasing doses of the opiate. Furthermore, changes in the rewarding effect of morphine are not dependent upon alterations in opioid receptors involved in the reinforcing mechanisms. Received: 31 October 1996 / Accepted: 7 February 1997     

八肽胆囊收缩素对抗吗啡抑制大鼠脑突触小体钙摄取的作用

用大鼠脑的膜制备观察吗啡和CCK-8对突触小体摄取~(45)Ca~(2+)的影响。吗啡(10 nmol/L～1μmo1/L)抑制突触小体对~(45)Ca的摄取,该作用能被1μmol/L纳洛酮完全阻断。CCK-8(10nmol/L～1μmol/L)本身能抑制突触小体~(45)Ca摄取,但它在10nmol/L和100 nmol/L时能对抗吗啡对~(45)Ca摄取的抑制作用,浓度提高到1μmol则不能对抗吗啡的这一作用。CCK-8抑制突触小体摄取~(45)Ca,以及对抗吗啡的~(45)Ca摄取抑制的作用,皆能被CCK受体拮抗剂丙谷酰胺(2μmol/L)所阻断.捉示CCK-8是通过激动CCK受体而拮抗吗啡抑制~(45)Ca摄取的,CCK-8的这一拮抗作用可能是其抗阿片作用的机理之一.