电针对吗啡戒断大鼠体质量和胃电图的影响

通过给大鼠连续注射递增量吗啡8d,建立吗啡戒断大鼠模型,停药后第2d开始给于强度为2mA,频率2～100Hz混频刺激.各组大鼠分别在实验前、实验第8d和实验第11d 18∶ 00测量体质量,在胃体、胃窦、体表投影处分别记录胃电图.观察电针足三里穴对其体质量和胃电图的影响.实验表明,模型组大鼠体质量与正常组比明显降低(P《0.01),胃电图频率、幅值改变,节律紊乱.电针组大鼠体质量与正常组比无显著差异,胃电图均有不同程度恢复.电针对吗啡戒断大鼠的体质量和胃肠功能紊乱具有良性调整作用.     

青藤碱对吗啡依赖与戒断小鼠脑组织nNOS活性的影响

目的:观察青藤碱对吗啡依赖与戒断小鼠中枢神经系统中大脑皮层、小脑、脑干的nNOS活性变化的影响。方法:剂量递增法建立小鼠吗啡依赖模型,青藤碱治疗前后用纳洛酮催瘾,观察戒断症状;化学比色法测各脑组织匀浆的nNOS活性。结果:青藤碱可扭转成瘾小鼠的体重下降趋势,减轻戒断症状;使由吗啡依赖与戒断引起异常变化的nNOS活性水平恢复到最终接近对照组水平。结论:青藤碱能显著减轻吗啡依赖小鼠的戒断征状,其机制可能与青藤碱影响各脑组织nNOS活性相关。     

鞘内注射NOS反义寡核苷酸抑制吗啡戒断大鼠脊髓和脑干NMDA1A受体mRNA表达的影响

运用逆转录－多聚酶联反应（RT－PCR）、鞘内注射和反义技术,研究脊髓水平一氧化氮（NO）对大鼠吗啡戒断反应和脊髓及脑干NMDA1A受体mRNA(NMDA1AR mRNA)表达的影响。结果表明,鞘内注射NOS反义寡核苷酸能明显减轻吗啡戒断反应,且脑型NOS（nNOS）反义寡苷酸的作用强于内皮型NOS(eNOS）反义寡核苷酸,吗啡依赖大鼠脊髓和脑干NMDA1AR mRNA表达增加,纳洛酮催促戒断,使其进一步增加;鞘内注射nNOS反义寡核苷酸,能明显抑制吗啡戒断大鼠脊髓和脑干NMDA1AR mRNA表达的增加;eNOS反义寡核苷酸也可抑制吗戒断大鼠脊髓NMDA1AR mRNA表达的增加,但作用弱于nNOS反义寡核苷酸,对脑干NMDA1AR mRNA表达无明显影响,上述结果提示：脊髓水平NO参与介导吗啡戒断反庆和NMDA受体表达的调控。     

青藤碱对吗啡依赖与戒断小鼠小脑与脊髓NO/nNOS系统的影响

本文旨在探讨青藤碱对吗啡依赖与戒断小鼠的小脑和胸腰段脊髓中一氧化氮（nitric oxide,NO）／神经元型一氧化氮合酶（neural nitric oxide synthase,nNOS）系统的影响及作用机制。采用吗啡剂量递增法建立小鼠吗啡依赖模型,用纳洛酮激发戒断症状,评价小鼠急性戒断时齿颤、扭体、直立、喷嚏、眼睑下垂等戒断症状,对成瘾小鼠用青藤碱（40mg／kg,i．P．）治疗后,再用纳洛酮激发观察戒断症状。半定量RT—PCR检测小鼠小脑和胸腰段脊髓nNOS mRNA表达变化,化学比色法和硝酸还原酶法分别测定小鼠小脑和胸腰段脊髓组织匀浆的nNOS活性与NO含量。结果显示：（1）青藤碱可以扭转由吗啡依赖引起的小鼠体重下降的趋势,减轻小鼠急性戒断时齿颤、扭体、直立、喷嚏、眼睑下垂等戒断症状;（2）青藤碱可降低小鼠吗啡依赖与戒断时在小脑与胸腰段脊髓中异常上调的nNOS mRNA水平,使酶活性下降到接近对照组水平。nNOS催化产生的NO含量与酶活性的变化一致;（3）单独使用青藤碱,小鼠没有出现类似吗啡引起的戒断症状,小脑与胸腰段脊髓中nNOS mRNA水平及酶活性没有异常升高。上述结果表明,青藤碱本身无成瘾性,但能显著减轻吗啡依赖小鼠的戒断征状,其作用机制可能与青藤碱影响小脑与脊髓中的NO／nNOS系统有关。     

毁损大鼠中缝背核内触液神经元对吗啡依赖和戒断的影响

目的:探索脑内远位触液神经元在吗啡依赖和戒断形成过程中的作用。方法:化学性神经元毁损、侧脑室引入霍乱毒素亚单位B与辣根过氧化物酶复合物(CB-HRP)神经示踪、TMB-ST呈色反应,Western blot、nNOS免疫组织化学。结果:毁损大鼠中缝背核内远位触液神经元后,纳洛酮催促的戒断症状明显减弱,戒断症状评分较戒断未毁损组降低约38%(P<0.05);给予溶媒和毁损触液神经元旁侧的大鼠戒断症状与戒断组比较未见明显变化(P>0.05)。毁损组脑片触液神经元密集区局部细胞损坏明显,仅在其毁损区边缘观测到少量CB-HRP阳性细胞。未毁损组CB-HRP标记细胞位置及数量恒定,形态清晰。毁损触液神经元后,脊髓背角nNOS阳性神经元计数及nNOS蛋白表达较戒断未毁损组减少明显(P<0.05),而较正常组和依赖组增加仍显著(P<0.01)。结论:毁损大鼠中缝背核内部分远位触液神经元可减弱吗啡戒断症状和脊髓背角神经元型一氧化氮合酶的表达,提示中缝背核内部分远位触液神经元可能参与了吗啡依赖和戒断的形成,NO介导脑内触液神经元与脊髓水平对吗啡依赖和戒断的调节。     

M受体对吗啡戒断大鼠脊髓和脑干NMDA受体基因表达及中脑导水管周围灰质中谷氨酸释放的调节

应用鞘内注射反义寡脱氧核苷酸技术和RT—PCR反应,观察毒蕈碱型乙酰胆碱受体(muscarinic acetylcholine receptor,M)对吗啡依赖大鼠脊髓和脑干NMDA受体NR1A和NR2A mRNA表达和中脑导水管周围灰质区(periaqueductal grey,PAG)中谷氨酸释放的影响。结果显示,吗啡依赖大鼠脊髓NR1A和NR2A mRNA表达明显升高,而脑干中NR1A和NR2A mRNA表达没有显著变化;注射纳洛酮后1h,吗啡戒断大鼠脊髓和脑干中NR1A和NR2A表达显著高于依赖组,经NMDA受体拮抗剂MK801(0．125mg／kg,i．p．)、M受体拮抗剂东莨菪碱(0．5mg／kg,i．p．)、M1受体拮抗剂呱伦西平(10mg/kg,i．p．)和NOS抑制剂L-NAME(10mg／kg,i．p．)处理后,脊髓和脑干中NR1A和NR2A基因表达都较戒断组明显减少。在纳洛酮激发前24h鞘内注射NR1A和M2受体的反义寡脱氧核苷酸(4μg／只),戒断症状评分值及脊髓和脑干的NR1A mRNA的表达均较对照组明显减少。吗啡依赖大鼠在纳洛酮注射前24h鞘内注射M2受体反义寡脱氧核苷酸(4μg/只),可以明显减少PAG内透析液中谷氨酸含量。上述结果提示：NMDA受体的基因表达和谷氨酸释放参与吗啡戒断过程,而这种表达受到M受体的调节。     

鞘内注射U0126对吗啡戒断大鼠脊髓神经元磷酸化CREB表达的影响

目的：研究鞘内注射细胞外信号调节激酶（ERK）抑制剂U0126对吗啡依赖大鼠纳洛酮催促戒断反应、脊髓磷酸化cAMP反应元件结合蛋白（p-CREB）表达的影响。方法：建立大鼠吗啡依赖和戒断模型,分为正常对照组、吗啡依赖组、吗啡戒断组、U0126组、溶媒（DMSO）组,采用行为学（n=8）、免疫组织化学（n=6）和Western blot（n=4）方法观察鞘内应用U0126对吗啡依赖大鼠纳洛酮催促戒断反应、脊髓p-CREB表达的影响。结果：①鞘内注射u0126可明显减轻吗啡依赖大鼠戒断症状,戒断组戒断症状评分为28．6±4．89,U0126组为22．5±4．09（P〈0．05）;戒断组促诱发痛评分（TEAscore）为13．5±2．55,U0126组为10．0±2．76（P〈0．05）。②鞘内注射U0126可明显减少胸腰段脊髓背角p-CREB阳性神经元的数目,U0126组为287±54,低于戒断组（380±71,P〈0．05）。 ③westem blot结果显示：鞘内注射U0126明显抑制吗啡戒断期间脊髓p-CREB表达的增加。结论：鞘内注射U0126能明显抑制吗啡戒断大鼠脊髓神经元p-CREB的表达。     

巴氯芬对慢性吗啡依赖后条件化位置偏好和戒断症状的抑制

小鼠连续7天腹腔注射吗啡(40mg/kg)建立条件化位置偏好模型,连续皮下递增注射吗啡(25、50、75、100、125、150mg/kg),成瘾后腹腔注射纳络酮(6mg/kg)诱导戒断症状(跳跃行为)建立戒断模型。腹腔注射GABAB受体激动剂巴氯芬(2mg/kg)可以有效地抑制吗啡诱导的条件化位置偏好和减轻纳络酮诱导的戒断症状,结果表明GABA系统参与动物成瘾后渴求和戒断过程,激动GABAB受体可以在一定程度上抑制成瘾的心理和生理戒断症状。     

MEK抑制剂抑制吗啡依赖及戒断大鼠脊髓神经元NOS的表达

目的：观察鞘内注射丝裂原活化蛋白激酶抑制剂U0126对吗啡依赖及戒断大鼠戒断症状和痛敏行为以及脊髓神经元NOS表达的影响。方法：采用吗啡依赖及戒断模型,分为正常对照组、依赖组、戒断组（戒断1h）、U0126组,分别作行为学评分（n=8）、免疫组织化学（n=6）和免疫印迹检测（n=4）。结果：①鞘内注射U0126可明显减轻吗啡依赖大鼠戒断症状,戒断组戒断症状评分为28．6±4．89,U0126组为22．5±4．09（P〈0．05）;戒断组TEA评分为13．5±2．55,U0126组为10．0±2．76（P〈0．05）;②鞘内注射U0126可明显减少L5节段脊髓背角Fos阳性神经元的数目,U0126组为287±54,低于戒断组（380±71,P〈0．05）;③U0126组nNOS和iNOS阳性神经元的数目分别为180±32、10．8±2．8,均低于戒断组（239±45,16．8±5．1,P〈0．05）,两给药组脊髓NOS蛋白的表达也显著减少。结论：MEK抑制剂能减轻吗啡依赖及戒断大鼠的戒断症状和在脊髓水平抑制NOS的表达,表明ERK可能参与调控NOS的表达。     

褪黑素对吗啡戒断小鼠下丘脑弓状核和中脑导水管周围灰质中β-内啡肽含量的影响

本文在观察腹腔注射褪黑素（melatonin,MEL）拮抗吗啡依赖小鼠纳洛酮催促戒断反应的同时,采用放射免疫分析法、免疫组织化学法,结合计算机图像处理技术,测定其对小鼠中脑导水管周围灰质（periaqueductal grey,PAG）、下丘脑弓状核（hypothalamic arcuatenucleus,Arc）中β-内啡肽（p-endorphin,β-EP）含量的影响。结果表明,MEL（80mg／kg体重）显著抑制吗啡依赖小鼠戒断反应（P〈0．05）的同时,可显著增加其中脑PAG中β-EP含量（P〈0．05）,减弱Arc中β-EP样免疫阳性反应强度（P〈0．05）。上述结果提示,MEL可提高吗啡戒断小鼠中脑PAG中β—EP含量,降低Arc中β-EP含量。     

长期注射吗啡对戒断后小鼠Y－迷宫空间识别记忆的影响

使用急性成瘾性药物会影响大脑功能,随着药物使用时间的延长,这种影响更加广泛、持久,并且在药物戒断后的很长时间内依然存在。实验表明,急性及短期吗啡给予小鼠和戒断均损伤了其Y迷宫空间识别记忆能力,但这种损伤短暂且可逆。本实验小鼠被连续注射吗啡（40 mg/kg&#8226;day,i p）或生理盐水21天,利用Y迷宫来检测长期吗啡给予后在戒断第2、9和19天,吗啡对小鼠空间识别记忆的影响。结果表明, 连续吗啡给予21天后,在戒断第2、9和19天,小鼠Y迷宫空识别记忆能力均受到损伤,提示长期给予小鼠吗啡会导致其空间识别记忆能力的长期损伤。     

Effects of Chronic Boron Exposure on Semen Profile

The possible changes in semen quality were studied in men living in a boron mining area. The subjects in the boron group had exposure to boron at an average level of 6.5 mg/day, as determined by urinary analysis. The results obtained by the boron group were compared to those obtained for the control group whose subjects were living in the same geographical area but away from the boron region; average exposure level was 1.4 mg/day for this group. The semen samples were analyzed according to the recommendations of the World Health Organization. Boron levels were established in the water samples obtained from various locations in the study region. In the boron mining fields where the subjects in the boron group live, water samples contained boron in the range of 1.4–6.5 mg/L, while the values were <0.01 mg/L for the water samples obtained from the region where the subjects of the control group reside. No negative effects were found in the sperm samples obtained from the subjects of the boron group.     

Altered μ-Opiate Receptor-G Protein Signal Transduction Following Chronic Morphine Exposure

Abstract: This laboratory has demonstrated that the longitudinal muscle/myenteric plexus (LMMP) preparation manifests pleiotropic responses to opioid agonists. For example, the μ-selective opiate receptor agonist sufentanil can produce a naloxone-reversible increase or decrease in the electrically stimulated formation of cyclic AMP, depending on its concentration. The present study demonstrates that the sufentanil facilitation and inhibition of stimulated cyclic AMP formation are mediated via G_s- and G_i-like G proteins, respectively. Inactivation of G_i (via pertussis toxin) not only abolishes sufentanil inhibition of cyclic AMP formation but also unmasks a facilitory effect. The latter response is eliminated following treatment with cholera toxin. In tolerant/dependent LMMP tissue, previously inhibitory concentrations of sufentanil produce a facilitation of cyclic AMP formation. However, this unmasked facilitory effect is resistant to cholera toxin. Thus, although inactivation of the inhibitory signal transduction pathway (via pertussis toxin) is sufficient to unmask excitatory sufentanil effects in opiate naive preparations, this mechanism cannot explain the reversal of sufentanil inhibition to facilitation that is observed in tolerant/dependent tissue. Instead, the chronic morphine-induced emergence of a μ-opiate receptor-coupled facilitory pathway that is either not expressed or not fully manifest in opiate naive LMMP tissue is suggested.     

慢性吗啡处理及戒断后大鼠海马CA1区钙结合蛋白Calbindin的表达变化

目的:观察慢性吗啡处理及戒断后大鼠海马CA1区中钙结合蛋白Calbindin(CB)的表达变化,为其功能研究提供形态学依据.方法:36只雄性SD大鼠随机分为吗啡依赖组和生理盐水对照组.吗啡依赖组大鼠腹膜腔注射吗啡,2次/d,起始剂量为5mg/kg,逐日递增5mg/kg,至第10d为50mg/kg;对照组注射同体积的生理盐水.于末次注射后动物分别存活3h、3d、14d和30d.免疫组化方法和相对平均灰度值检测海马CAl区CB的表达变化.结果:在生理盐水处理组各存活时间点海马CAI区CB的表达相同.和生理盐水对照组相比,吗啡依赖组3h时海马CA1区CB的表达明显增加(P<0.05),3 d时进一步增加,至第14 d时CA1区CB的表达开始恢复.结论:慢性吗啡处理及戒断后海马CA1区CB的表达上调可能对戒断早期海马神经元有保护作用.     

Effects of Mild Chronic Intermittent Cold Exposure on Rat Organs

Cold adaptation is a body''s protective response to cold stress. Mild chronic intermittent cold (CIC) exposure has been used to generate animal models for cold adaptation studies. However, the effects of mild CIC exposure on vital organs are not completely characterized. In the present study, we exposed rats to mild CIC for two weeks, and then measured the body weights, the weights of brown adipose tissue (BAT), the levels of ATP and reactive oxygen species (ROS) in the brains, livers, hearts, muscles and BATs. Rats formed cold adaptation after exposure to CIC for two weeks. Compared to rats of the control group that were hosted under ambient temperature, rats exposed to mild CIC showed a lower average body weight, but a higher weight of brown adipose tissue (BAT). Rats exposed to CIC for two weeks also exhibited higher levels of ATP and ROS in all examined organs as compared to those of the control group. In addition, we determined the expression levels of cold-inducible RNA binding protein (Cirbp) and thioredoxin (TRX) in rat tissues after 2 weeks of CIC exposure. Both Cirbp and TRX were increased, suggesting a role of these two proteins for establishment of cold adaptation. Together, this study reveals the effects of mild CIC exposure on vital organs of rats during CIC exposure.     

Opiate Modulation of Striatal Dopamine and Hippocampal Norepinephrine Release Following Morphine Withdrawal

When opiates are abruptly withdrawn after chronic treatment, increases in hippocampal noradre-nergic function are observed which are accompanied by decreases in striatal dopamine release. The latter effects have to shown to persist for several weeks following the onset of opiate withdrawal. We examined the long-term effects of opiate withdrawal on 4-aminopyridine and potassium stimulated release of striatal dopamine and hippocampal norepinephrine. Tissue samples were obtained either from rats that had been exposed to opiate withdrawal following a seven day morphine infusion or sham treated control subjects. At 48 hours after the onset of withdrawal (cessation of morphine infusions), slices were loaded with [³H] neurotransmitter, washed extensively, and exposed to different drug treatments. 4-aminopyridine induced concentration related increases in striatal dopamine release, which was 36% calcium independent. Similar values for fractional release of striatal dopamine were obtained in morphine withdrawn and control subjects, for both potassium and 4-aminopyridine induced release. In addition, thresholds for 4-aminopyridine or potassium induced release of striatal dopamine did not differ between control and morphine withdrawn subjects. Treatment with 1.0 M morphine sulfate potentiated potassium evoked release of norepinephrine to an equal extent in both morphine withdrawn and sham treated hippocampal tissue. Exposure to a threshold concentration of potassium (8.0 mM), stimulated increased release of hippocampal norepinephrine in a significantly greater fraction of tissue samples obtained from morphine withdrawn animals. Although these results do not support changes in striatal dopamine release following opiate withdrawal, opiate mechanisms appear to be important determinants of in vitro hippocampal norepinephrine release.     

Electroacupuncture Facilitates Recovery of Male Sexual Behavior in Morphine Withdrawal Rats

The effect of electroacupuncture (EA) on the sexual behavior of male rats undergoing morphine withdrawal was studied by measuring various parameters of sexual behavior. In addition, the total serum testosterone (TST) concentrations in male rats at different times of morphine administration and abstinence were measured. Acute and chronic administration of morphine severely inhibited the sexual behavior of the rats and lowered their TST concentrations. TST concentrations recovered to normal within 24 h after the last morphine injection, while sexual behavior remained suppressed for at least 7 days. Electroacupuncture (2/100 Hz alternately) administered once daily for 7 days during morphine withdrawal facilitated the recovery of male sexual behavior and increased TST concentrations to above normal. The effect of EA on sexual behavior may involve both neuronal and hormonal pathways.