低频率电刺激通过Ras同源基因/Rho相关蛋白激酶途径调节自噬对癫痫大鼠的作用研究

目的 探究低频率电刺激（LFS）对癫痫的作用及其可能的作用机制。方法 将60 只SD 大鼠按随机数字表法分为对照组、癫痫模型组、假刺激组和LFS 治疗组，每组各15 只。氯化锂-匹鲁卡 品法建立癫痫大鼠模型。记录大鼠Racine 评分和脑电图，Morris水迷宫实验检测大鼠空间学习记忆能 力；苏木素-伊红（HE）染色和尼氏染色检测大鼠海马CA1 区病理学变化；脱氧核糖核苷酸末端转移酶 介导的缺口末端标记法（TUNEL）染色检测大鼠海马神经细胞凋亡；Western blot 检测大鼠海马Ras同源 基因家族成员A（RhoA）、Rho 相关蛋白激酶1（ROCK1）、ROCK2、自噬和凋亡相关蛋白表达；逆转录聚合 酶链反应（RT-PCR）检测大鼠海马RhoA、ROCK1 和ROCK2 mRNA 表达。结果 与对照组比较，癫痫模 型组大鼠出现连续性棘波，Racine 评分［（4.23±0.29）分］、逃跑潜伏期［（49.36±4.69）s］、神经细胞凋亡 率［（27.52±2.95）%］和B 淋巴细胞瘤-2（Bcl-2）相关X［Bax，（0.82±0.07）］、裂解-caspase3［c-caspase3， （1.70±0.15）］、微管相关蛋白1A/1B轻链3BⅡ/微管相关蛋白1A/1B轻链3BⅠ［LC3Ⅱ/LC3Ⅰ，（5.20±0.42）］ 和Beclin1（0.73±0.05）蛋白表达水平明显升高（均P＜ 0.05），RhoA、ROCK1 和ROCK2 mRNA 和蛋白表达 水平均明显升高（均P ＜ 0.05），游泳距离［（240.68±22.91）cm］、平台停留时间［（39.89±2.20）s］、神经细 胞数量（17.13±3.14）、尼氏体数量（6.75±1.09）以及Bcl-2（0.24±0.02）和p62（0.20±0.02）蛋白表达水平 明显降低（P＜ 0.05）；与假刺激组比较，LFS治疗组大鼠波峰明显下降，Racine 评分［（2.82±0.23）］分、逃 跑潜伏期［（34.83±3.85）s］、神经细胞凋亡率［（9.25±0.91）%］及Bax（0.43±0.05）、c-caspase3（0.53±0.02）、 LC3 Ⅱ /LC3 Ⅰ（1.17±0.11）和Beclin1（0.36±0.02）蛋白表达水平明显降低（均P ＜ 0.05），RhoA、ROCK1 和ROCK2 mRNA 和蛋白表达水平均明显降低（均P ＜ 0.05），游泳距离［（284.21±22.36）cm］、平台停留 时间［（46.85±2.93）s］、神经细胞数量（47.00±5.07）、尼氏体数量（33.75±2.90）和Bcl-2（0.87±0.07）、p62 （0.96±0.05）蛋白表达水平明显升高（均P ＜ 0.05）。结论 LFS 可能通过抑制Rho/ROCK 途径调节自噬 发挥抗癫痫作用。     

沙格列汀对糖尿病并发抑郁症大鼠认知功能的影响

目的 探讨二肽基肽酶-Ⅳ（DPP-4）抑制剂沙格列汀对糖尿病并发抑郁症（DD）大鼠认知 功能的影响，以及可能的机制。方法 48 只无特定病原体级健康雄性SD 大鼠随机分为对照组、模型 组、阳性药组和沙格列汀组，每组12 只。采用高脂乳剂灌胃14 d+经尾静脉注射链脲佐菌素（STZ）+28 d 慢性刺激制备DD 模型，在接受慢性刺激的同时，阳性药组大鼠给予二甲双胍+氟西汀胶囊灌胃，沙格 列汀组大鼠给予沙格列汀灌胃，模型组和对照组则给予等量的生理盐水，每天1 次，连续28 d。旷场实 验和Morris水迷宫实验检测大鼠对周围陌生环境探索能力和学习记忆能力，苏木素-伊红染色观察大 鼠海马组织形态变化，脱氧核糖核苷酸末端转移酶介导的缺口末端标记法（TUNEL）染色检测海马组织 中神经细胞凋亡，酶联免疫吸附试验检测海马组织中IL-1β、IL-6 和TNF-α 水平。结果 与对照组比 较，模型组、阳性药组和沙格列汀组大鼠水平穿越格数［（62.25±5.53）、（85.92±4.58）、（78.25±6.02）个 比（104.75±6.11）个］和直立次数［（7.33±1.97）、（11.17±1.34）、（9.33±2.27）次比（17.50±1.68）次］均减 少（均P ＜ 0.01），逃避潜伏期延长［（51.75±8.01）、（29.58±5.14）、（35.42±3.48）s 比（18.17±3.43）s；均P ＜ 0.01］，而目标象限记忆时间缩短［（15.00±3.52）、（26.08±5.88）、（21.25±4.35）s 比（34.42±5.28）s；均P ＜ 0.01］，大鼠海马组织中神经细胞凋亡指数［ （74.66±4.62）%、（47.23±6.24）%和（39.22±2.80）% 比 （9.22±0.87）%］升高（均P＜ 0.01），IL-1β［（41.26±5.82）、（21.01±3.84）、（29.89±7.42）ng/g比（12.22±5.02）ng/g］、 IL-6［（80.792±3.59）、（50.73±7.18）、（61.69±6.29）ng/g 比（31.90±4.79）ng/g］和TNF-α［（90.94±8.72）、 （66.57±9.93）、（77.70±6.96）ng/g 比（49.88±5.24）ng/g］水平升高（P ＜ 0.05 或P ＜ 0.01）；与模型组比 较，阳性药组和沙格列汀组大鼠水平穿越格数和直立次数均升高（均P ＜ 0.01），逃避潜伏期缩短（均 P＜ 0.01），而目标象限记忆时间延长（均P＜ 0.01），大鼠海马组织中神经细胞凋亡指数降低（均P ＜ 0.01），IL-1β、IL-6 和TNF-α水平降低（均P＜ 0.01）。结论 沙格列汀可改善DD 大鼠认知功能损伤，其 机制可能是通过减轻海马组织炎性反应，从而减轻海马损伤有关。     

高压氧早期干预对创伤后应激障碍模型大鼠行为及海马核因子E2相关因子2和血红素加氧酶1表达水平的影响

目的 探讨高压氧早期干预对创伤后应激障碍（PTSD）模型大鼠行及海马核因子 E2 相 关因子 2（nuclear factor erythroid 2-related factor 2，Nrf2）及血红素加氧酶 1（HO-1）基因表达的影响。 方法 将 32 只雄性 Sprague-Dawley 大鼠随机分为对照组（sham 组）、高压氧组（HBO 组）、模型组（ESPS 组）、模型 + 高压氧早期干预组（ESPS+HBO 组），每组 8 只。ESPS 组和 ESPS+HBO 组大鼠经增强型单次 延长应激（ESPS）构建 PTSD 模型，其他两组不接受 ESPS 造模，但置于同一实验室环境。造模结束 24 h 后，各组大鼠置于高压氧舱进行 1 h 高压氧（2.5 个大气压，100% O2 ）或常压空气干预，连续 5 d。干预 结束后将大鼠放回原饲养笼中不受打扰饲养 7 d。通过旷场实验、高架十字迷宫实验以及条件性恐惧 性实验观察大鼠的行为表现，并通过蛋白免疫印迹法（Western Blot）检测大鼠海马组织 Nrf2 和 HO-1 的 表达情况。结果 （1）各处理组旷场内总运动距离的差异无统计学意义（P＞ 0.05）；ESPS 组中心区运 动时间 ［（20.52±9.25）s］和进入旷场中心区次数［（15.22±4.38）次］均显著低于sham组［（44.94±14.49）s、 （32.77±6.22）次］，而 ESPS+HBO 组［（35.49±13.04）s、（21.50±5.98）次］则显著高于 ESPS 组（均P＜ 0.05）。 （2）与 sham 组开臂停留时间［（54.47±23.23）s］、开臂停留时间百分比［（17.91 ±8.11）%］和进入开臂次 数［（10.54±3.85）次］比较，ESPS 组各指标［（26.18±8.56） s］、［（7.23±4.24）%］和［（3.10±1.96）次］均 显 著 降 低，而 ESPS+HBO 组 各 指 标［（40.77±16.66）s］、［（13.66±8.81）%］和［（6.40±1.71）次］均 显 著高于 ESPS 组（均P＜ 0.05）。（3）ESPS 组环境诱发僵直时间［（183.21±25.83）s］和声音诱发僵直时间 ［（202.03±47.79）s］均显著高于 sham 组和 ESPS+HBO 组（均P＜ 0.05）。（4）ESPS 组海马 Nrf2（0.23±0.08） 和 HO-1（0.84±0.13）的蛋白相对表达水平均显著低于 sham 组和 ESPS+HBO 组（均P＜ 0.05）。（5）sham 组 与 HBO 组在上述行为和分子表达指标之间的差异均无统计学意义（均P＞ 0.05）。结论 高压氧早期干 预可能通过调节海马的抗氧化系统 Nrf2/HO-1 的表达水平改善 PTSD 大鼠的焦虑样行为和认知损伤。     

氟西汀对慢性不可预见应激模型大鼠前额叶皮质磷脂酰乙醇胺的影响

目的 探讨氟西汀对慢性不可预见应激（CUS）模型大鼠前额叶皮质磷脂酰乙醇胺（PE）的 影响。方法 按随机数字表法将18 只SD 大鼠随机分为对照组（Sham组）、模型组（CUS 组）和氟西汀组 （Flx组）。CUS组和Flx组均接受CUS造模，并且在造模后接受生理盐水（1 ml/kg）或氟西汀（10 mg/kg）腹腔 注射，连续14 d；Sham组不进行CUS造模，但是每天接受腹腔注射生理盐水。14 d后处死大鼠，取前额 叶皮质进行脂质组学分析，比较各处理组前额叶皮质总的PE和PE小分子相对丰度差异。结果 （1）与 Sham 组［（10.50±7.32）×1011］比较，CUS 组PE 相对丰度［（11.95±8.46）×1011］明显减低（P ＜ 0.01），而 Flx 组［（10.31±9.16）×1011］差异则无统计学意义（P ＞ 0.05）；（2）与Sham 组比较，CUS 组3 个PE 小分子 相对丰度减低，分别为PE（36：4p）（68.67±14.68）、PE（38：3p）（49.73±19.55）、PE（38：4p）（76.10±7.84）， 差异均有统计学意义（均P ＜ 0.05）；（3）与CUS 组比较，Flx 组6 个PE 小分子相对丰度减低，包括PE （36：4）（72.53±10.22）、PE（36：2）（87.86±8.26）、PE（38：5p）（75.66±9.53）、PE（38：5）（89.93±9.79）、PE （38：4）（86.55±5.40）、PE（40：7p）（81.57±7.55），差异均有统计学意义（均P＜ 0.05）；（4） 与Sham 组比较， Flx 组6 个PE 小分子相对丰度减低，包括PE（38：4p）（75.85±5.63）、PE（38：3p）（44.22±12.61）、PE（38：4） （82.49±9.41）、PE（40：5p）（78.01±5.31）、PE（36：4）（76.00±6.34）、PE（38：6）（77.45±13.06），差异均有统计 学意义（均P ＜ 0.05）。结论 CUS 模型大鼠前额叶皮质内PE 水平异常，氟西汀可以调节CUS 模型大鼠 前额叶皮质的PE 水平。     

卒中后抑郁大鼠认知功能障碍与Cx36表达的 相关性研究

目的 探讨卒中后抑郁（PSD）大鼠海马缝隙连接蛋白Cx36 与认知功能障碍的相关性,探 寻PSD认知功能障碍的潜在发病机制。方法 将42 只大鼠随机分为正常组、卒中组、抑郁组、PSD组、 生理盐水组、甘珀酸（CBX）组和全反式维甲酸（ATRA）组,每组6 只。抑郁组每天随机给予1 种慢性不可 预测的温和性刺激并孤养;向卒中组大鼠的运动皮层注射内皮素-1 制备局灶性缺血型大鼠模型,PSD 组、生理盐水组、CBX 组和ATRA 组在卒中组的基础上叠加抑郁刺激建立PSD 模型。在PSD 造模的同 时,PSD 组不进行干预;生理盐水组每天腹腔注射生理盐水1 ml;ATRA组每天腹腔注射浓度为1 mg/ml 的1 ml 乙醇和磷酸盐缓冲液（按1∶9 配置）;CBX 组按照20 mg/kg 的标准每天腹腔注射CBX。于卒中 术后28 d,采用糖水实验、水迷宫实验、穿梭实验检测大鼠的兴趣缺失感、空间记忆能力、学习记忆能 力,验证PSD认知障碍模型是否诱导成功;采用Real-time PCR检测大鼠海马Cx36 mRNA表达变化;采用 Western blotting 检测和免疫荧光检测大鼠海马Cx36 蛋白的表达量和平均荧光强度。结果 术后28 d, PSD 组大鼠体重［（257.05±4.74）g］低于正常组［（352.00±7.99）g］、卒中组［（303.95±4.63）g］,差异有 统计学意义（P＜0.05）;PSD组大鼠24 h糖水饮用率［（61.92±3.12）%］低于正常组［（83.40±5.38）%］、卒中 组［（88.03±3.65）%］、ATRA组［（71.15±4.55）%］,高于CBX组［（49.62±5.85）%］,差异有统计学意义（P＜ 0.05）;PSD组大鼠水迷宫潜伏时间［（51.18±4.14）s］长于正常组［（9.05±2.22）s］、卒中组［（9.06±2.25）s］、 ATRA组［（32.92±2.29）s］,短于CBX 组［（91.13±3.27）s］,差异有统计学意义（P＜ 0.05）;PSD组穿梭实验 主动逃避次数［（10.67±1.51）次］少于正常组［（18.00±2.10）次］、卒中组［（16.5±1.87）次］和ATRA 组 ［（13.83±1.17）次］,多于CBX 组［（7.00±1.26）次］,差异有统计学意义（P＜ 0.05）。术后28 d,PSD组海马 区Cx36 mRNA 表达量（0.50±0.03）低于正常组（1.04±0.07）、卒中组（1.07±0.10）和ATRA组（0.76±0.11）, 高于CBX 组（0.20±0.06）,差异有统计学意义（P＜ 0.05）;PSD组海马区Cx36 蛋白相对表达量（0.60±0.07） 低于正常组（0.86±0.05）、卒中组（0.88±0.03）和ATRA 组（0.77±0.07）,高于CBX 组（0.56±0.02）,差异 有统计学意义（P ＜ 0.05）;PSD 组海马区Cx36 蛋白平均荧光强度（0.36±0.03）低于正常组（1.00±0.03）、 卒中组（0.97±0.03）和ATRA 组（0.50±0.02）,高于CBX 组（0.21±0.03）,差异有统计学意义（P ＜ 0.05）。 结论 PSD 大鼠海马Cx36 蛋白水平降低,CBX 干预能降低Cx36 蛋白表达并且大鼠认知功能障碍加重, ATRA干预能增加Cx36 蛋白的表达并且大鼠认知功能障碍稍有好转。     

氯化锂通过Akt/GSK-3β 通路抑制苯丙胺 诱导的大鼠行为敏化

目的 探讨氯化锂对苯丙胺诱导的大鼠行为敏化的影响及蛋白激酶B（Akt）/ 糖原合成激 酶-3β（GSK-3β）通路在其中的作用。方法 40 只雄性SD 大鼠随机分为空白对照组（S-S 组,n=13）、苯 丙胺敏化组（S-A 组,n=13）和氯化锂预处理苯丙胺敏化组（L-A组,n=14）,S-S 组大鼠接受连续5 d的生 理盐水（10 ml/kg）预处理+ 生理盐水（10 ml/kg）腹腔注射; S-A 组大鼠接受连续5 d 的生理盐水（10 ml/kg） 预处理+苯丙胺（1.5 mg/kg）腹腔注射;L-A组大鼠接受5 d的氯化锂（100 mg/kg）预处理+苯丙胺（1.5 mg/kg） 腹腔注射,之后停药6 d,第12 天时每组随机选取6 只大鼠接受低剂量苯丙胺腹腔注射。采用自发活 动视频分析记录系统记录3 组大鼠每组随机6 只分别在用药第1 天和第12 天时150 min 内的自发活 动。第12 天时在未接受行为学测试的3 组大鼠中每组随机6 只,采用Western blot 检测其前额叶皮质磷 酸化Akt（p-Akt）/Akt、磷酸化GSK-3β（p-GSK-3β）/GSK-3β表达水平。结果 在用药第1 天时,S-A组 大鼠的自发活动总距离［（26 826.50±5 987.96） cm］明显高于S-S 组［（1 861.50±612.49） cm］和L-A 组 ［（7 599.00±4 778.14） cm］,差异均有统计学意义（均P＜0.05）。在第12天时,苯丙胺激发实验中S-A组大 鼠自发活动总运动距离［（43 823.83±5 831.88） cm］明显高于S-S 组［（14 274.50±4 724.98） cm］和L-A组 ［（17 823.50±4 313.64） cm］,差异均有统计学意义（均P ＜ 0.05）。S-A 组大鼠前额叶皮质p-Akt/Akt 比 值和p-GSK-3β/GSK-3β比值均低于S-S 组（均P ＜ 0.05）,而L-A 组大鼠前额叶皮质p-Akt/Akt 比值和 p-GSK-3β/GSK-3β比值高于S-A组（均P＜0.05）。结论 氯化锂可以抑制苯丙胺诱导的大鼠行为敏化, 其机制可能是通过Akt/GSK-3β 通路介导。     

SB-399885阻断5-羟色胺6受体/雷帕霉素靶蛋白 途径对精神分裂症大鼠认知和记忆障碍的改善作用

目的 研究 5- 羟色胺 6 受体（HTR6）拮抗剂 SB-399885 通过阻断 HTR6 / 雷帕霉素靶蛋 白（mTOR）途径对精神分裂症大鼠认知和记忆障碍的作用。方法 将 40 只 SD 大鼠随机分为 4 组：空 白对照组、精神分裂症模型组（SZ 组）、SZ+SB-399885 组（10 mg/kg）、阳性对照组（SZ+ 利培酮，0.1 mg/kg）， 每组各 10 只大鼠。采用 MK-801 建立 SZ 大鼠模型。新物体辨别实验检测大鼠视觉识别记忆，Morris 水 迷宫实验检测大鼠认知能力，被动回避实验检测大鼠学习记忆能力，乙酰胆碱酯酶（AChE）活性测定 试剂盒检测大鼠海马和大脑皮质 AChE 活性，TUNEL 染色法检测大鼠海马 CA1 区神经细胞凋亡情况， Western blot 检测大鼠海马 HTR6 / mTOR 途径相关蛋白的表达。 结果 5-HT6 受体拮抗剂 SB-399885 和 利培酮均能显著改善 SZ 大鼠视觉识别记忆障碍、认知障碍和学习记忆障碍（均P＜0.05）。与SZ组比较， SZ+SB-399885组大鼠海马AChE活性［（0.008±0.001）μmol/（min·mg）］、神经细胞凋亡率［（21.75±4.45）%］、 HTR6 蛋白表达（0.56±0.10）和 mTOR 活性（0.41±0.05）均显著降低（均P＜ 0.05）；阳性对照组大鼠海马 和大脑皮质 AChE 活性显著降低（均P＜ 0.05），大鼠海马神经细胞凋亡率［（19.28±5.22）%］、HTR6 蛋 白表达（0.40±0.10）和 mTOR 活性（0.33±0.05）均显著降低（均P＜ 0.05）。结论 5-HT6 受体拮抗剂 SB- 399885 可能通过阻断 HTR6 / mTOR 途径改善精神分裂症大鼠认知和记忆障碍。     

健康老年人脑单光子发射计算机体层摄影术及磁共振显像的研究

目的研究健康老年人脑的功能性和结构性影像学特征。方法将73名年龄≥60岁的健康志愿者按年龄分为60～65岁组（第1组）、66～70岁组（第2组）和>70岁组（第3组）,采用单光子发射计算机体层摄影术对3组进行脑组织检查,并对其中的29名自愿者进行脑磁共振显像检查。结果（1）经方差分析,第2组和第3组脑组织几乎所有部位（除右丘脑和扣带回外）的灌注均低于第1组,其中第2组右顶叶灌注的放射性计数比值（RAR）为0.87±0.18,低于第1组（RAR=0.98±0.17;P<0.01）;（2）经配对t检验,除第2组的双侧顶叶外,3组颞叶和顶叶的灌注均为右侧高于左侧（P<0.01和0.05）;（3）经方差分析,第3组的灰质体积占颅内容积的百分比［（47.59±1.26）%］小于第2组［（49.43±1.30）%］,总脑脊液体积占颅内容积的百分比［（14.61±3.16）%］大于第1组［（12.41±0.73）%］和第2组［（11.94±1.27）%］,右侧海马体积［（2.04±0.23）cm     

蛋白激酶B/叉头型转录因子O亚型通路在腹侧海马损伤大鼠中的作用

目的 建立精神分裂症的腹侧海马损伤大鼠模型，并探讨模型大脑中蛋白激酶B（PKB/ Akt）和叉头型转录因子O 亚型（FoxOs）蛋白磷酸化活性水平。方法 健康雄性SD 乳鼠随机分为2 组，腹 侧海马损伤组（NVHL）和对照组，每组各8 只大鼠，利用脑立体定位技术注射鹅膏蕈氨酸制备腹侧海马 损伤模型。第56～60 天时，大鼠接受自发活动、前脉冲抑制（PPI）等行为学测试。测试完成3 d 后取大 鼠脑组织进行形态学观察。采用Western blot 测定大鼠皮层和纹状体Akt/FoxOs磷酸化水平。结果 与 对照组大鼠相比，NVHL大鼠腹侧海马明显损伤。安非他命诱导的自发探索活动增加［（1 014±72）次 比（753±87）次，P ＜ 0.01］，PPI 受损［PP6：（5.04±3.24）% 比（22.08±14.26）%，PP9：（11.26±5.24）% 比 （25.16±13.45）%，PP12：（8.17±10.45）% 比（29.16±10.25）%，均P ＜ 0.01］。大脑皮层Akt/FoxO1 和纹状 体Akt/FoxO1/FoxO3a磷酸化水平降低（ P＜0.05）。结论 腹侧海马损伤是一个广泛应用的精神分裂症 动物模型，海马损伤后大鼠皮层和纹状体Akt/FoxOs蛋白磷酸化水平下降，提示该通路参与了精神分裂 症的过程。     

大鼠脑损伤后NMDAR1表达及其认知障碍变化的关系

目的同步考量脑损伤后大鼠与认知功能较为密切的脑区N-甲基-D-天冬氨酸受体1（NMDAR1）表达与认知功能的变化。方法参照Feeney法建立大鼠创伤性脑损伤模型,伤后1d,2d,4d,7d1）．2免疫组化SABC法检测大鼠额叶皮质、海马区、基底前脑区NMDAR1表达,以行走实验、平衡实验及记忆功能测定评估大鼠认知障碍变化。结果轻、中型脑损伤组大鼠于伤后2d认知障碍最严重,分别于伤后3,7d基本恢复正常。轻型、中型脑损伤组脑额叶皮质、海马区、基底前脑区NMDAR1均于伤后1d升高,于2d降至较低水平后再呈缓慢增高趋势,与认知障碍变化趋势呈同步变化,且中型脑损伤组NMDAR1表达高于假手术组与轻型脑损伤组（P〈0．05）。结论大鼠经创伤性脑损伤后,额叶皮质、海马区、基底前脑区细胞中的NMDAR1含量和损伤后认知障碍的变化趋势有相似性;创伤性脑损伤后表达增加的NMDAR1对大鼠认知功能有加重损害作用。     

In ethanol

Slide-mounted tissue sections of brain were incubated with several reversibly binding [³H]ligands to label receptors. Exposure of these labeled, mounted tissue sections to ethanol solutions for dehydration resulted in a substantial loss of receptor bound ligands in all cases, even when the tissues were fixed with formaldehyde vapors before exposure. Thus, serious problems can be introduced into in vitro labeling autoradiographic procedures by exposure of sections to aqueous or organic media.     

Tolerance to the antinociceptive effects of ethanol during ethanol withdrawal

Prior research has indicated that tolerance develops to the antinociceptive effects of ethanol and continues even during withdrawal. Three potential pharmacological mechanisms for this tolerance are examined, using nitrendipine (L-type calcium channel blocker), theophylline (adenosine A1/A2 antagonist) and flumazenil (benzodiazepine antagonist). Rats received 10 days of exposure to an ethanol-containing liquid diet (6.5% w/v). A radiant heat tail-flick assay was used to assess hyperalgesia at 12 h after removal of the liquid diet, as well as tolerance to the effects of cumulative doses of ethanol (0.5-2 g/kg). Co-administration of flumazenil (10 mg/kg, i.p., b.i.d.), nitrendipine (5 mg/kg, i.p., b.i.d.) or theophylline (1 mg/kg, i.p., b.i.d.) with chronic ethanol prevented development of the hyperalgesia produced by ethanol withdrawal, but only theophylline reduced tolerance to the antinociceptive effects of ethanol administered during ethanol withdrawal. In contrast, when administered during ethanol withdrawal, theophylline (1-10 mg/kg) blocked the anti-hyperalgesic effects of ethanol during ethanol withdrawal, whereas nitrendipine (5-25 mg/kg) enabled ethanol to produce levels of antinociception comparable to non-dependent rats. These findings indicate that L-type calcium channels and adenosine receptors play important, but differing roles in the development of hyperalgesia during withdrawal, and to tolerance to the antinociceptive effects of ethanol.     

Increased ethanol intake after prenatal ethanol exposure: studies with animals

This review analyses the most relevant studies in which ethanol intake was measured after prenatal exposure to the drug. Despite the variety in methodology, in most such studies this prenatal experience induced a higher consumption of ethanol. Several variables that may affect the expression of this phenomenon are discussed, such as gender, age at testing, period of ethanol exposure, ethanol dose and conditions during the test. The mechanisms proposed in all these studies to explain the increased ethanol intake effect are also discussed. Some of these mechanisms are related to the teratological effects of the drug on the neurochemical systems involved in the reinforcing effects of abuse drugs, as well as on the regulatory systems of stress response. Another explanation of this phenomenon is also proposed in terms of associative learning. Specifically, the increased ethanol intake effect may be the result of a conditioned preference for ethanol acquired by the fetus when exposed to the drug during the last days of gestation.     

Minocycline reduces ethanol drinking

Alcoholism is a disease characterized by continued alcohol consumption despite recurring negative consequences. Thus, medications that reduce the drive to consume alcohol can be beneficial in treating alcoholism. The neurobiological systems that regulate alcohol consumption are complex and not fully understood. Currently, medications are available to treat alcoholism that act either by causing accumulation of a toxic metabolite of ethanol, or by targeting specific transmitter receptors. The purpose of our study was to investigate a new potential therapeutic pathway, neuroimmune interactions, for effects on ethanol consumption. We hypothesized that neuroimmune activity of brain glia may have a role in drinking. We utilized minocycline, a second generation tetracycline antibiotic that has immune modulatory actions, to test our hypothesis because it is known to suppress microglia, and to a lesser extent astroglia, activity following many types of insults to the brain. Treatment with 50mg/kg minocycline significantly reduced ethanol intake in male and female C57Bl/6J mice using a free choice voluntary drinking model. Saline injections did not alter ethanol intake. Minocycline had little effect on water intake or body weight change. The underlying mechanism whereby minocycline reduced ethanol intake requires further study. The results suggest that drugs that alter neuroimmune pathways may represent a new approach to developing additional therapies to treat alcoholism.     

Running increases ethanol preference

Wheel running performed by rats is reinforcing, rewarding and possibly addictive. In this study we analyzed if wheel running could affect ethanol preference. Lewis rats, known to be both addiction-prone and to develop an excessive wheel running behavior, were given access to ethanol in a two-bottle free-choice paradigm. The animals reached a high and stable ethanol intake after 5 weeks. In the next phase, rats were subjected to ethanol withdrawal for 1, 2 or 4 weeks with or without access to running wheels. Finally animals were again given access to ethanol in the same two-bottle free-choice paradigm, combined with access to running wheels. The rats that ran in running wheels during 1 or 2, but not 4, weeks of ethanol withdrawal increased both ethanol intake and preference as compared with the control group that did not have access to the wheels. Previous studies have demonstrated that low doses of morphine increases ethanol preference. Here we show that also running potentiates ethanol intake and preference. Thus, running which shares many of the reinforcing properties with addictive drugs appears to potentiate rats to an increased preference for ethanol. Our results describe a behavioral interaction where running increases ethanol consumption.     

The neurotoxicity of ethanol

ABSTRACT- Alterations in nervous system functioning following acute and chronic ethanol exposure have been studied in a great number of experimental investigations. Results from many of these investigations can be difficult to interpret, particularly since a variety of techniques and exposure models are employed. This review emphasizes those studies which, in the opinion of the author, fit into a pattern where results from studying one function of the nervous system is in accordance with results from studying another. Thus, the fluidizing effect of ethanol on the neuronal membrane - an effect which ethanol shares with anaesthetics - leads to a change in protein function which in turn affects ion transport such as Na⁺ and Ca⁺⁺ across the membrane due to changes in the ion channels. Cation influx is probably directly coupled to neurotransmitter release which is in agreement with the finding that ethanol exposure results in inhibition of Na⁺ and Ca⁺⁺ current as well as acetylcholine release. The sensitation of the dopaminergic system after ethanol exposure may also be related to the changes in cation flux, and the changes in this system probably play a crucial rôle in the development of tolerance and withdrawal symptoms. Other aspects such as impairment of protein synthesis, altered GABA function of impairment of neuron excitability and conduction are more difficult to place in proper perspective. The rôle of acetaldehyde in acute as well as chronic ethanol intoxication also remains a controversy. These may, however, be secondary phenomena to primary changes in different part of the nervous system not necessarily important in the clinical situation. Behavioural and anatomical studies particularly from recent years have shown that experimental animals develop memory disturbances following chronic exposure even when kept on sufficient diet. These findings argue strongly for a direct toxic effect of ethanol, and are furthermore compatible with behavioural changes in chronic alcoholics, dominated by memory impairment. Since it has been argued that the cholinergic system plays a significant rôle for memory function, a possible explanation for some of the psychological and anatomical deficits caused by ethanol is thus the changes in the function of the cholinergic system particularly in the hippocampal regions.     

Systemic ethanol administration elevates deoxycorticosterone levels and chronic ethanol exposure attenuates this response

Systemic ethanol administration is known to elevate levels of the GABAergic neuroactive steroid 3alpha,21-dihydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THDOC). 3alpha,5alpha-THDOC is synthesized from deoxycorticosterone (DOC) by metabolism in adrenals and brain. The present study investigated DOC levels in plasma and brain following ethanol administration to na?ve and ethanol-exposed rats. Rats were administered ethanol (2 g/kg, i.p.) or saline and DOC levels were measured in plasma and brain regions by radioimmunoassay. Chronic ethanol-exposed rats were administered an ethanol challenge (2 g/kg, i.p.) following 15 days of ethanol liquid diet consumption. Ethanol administration markedly increased DOC levels in plasma, cerebral cortex, hippocampus, hypothalamus, cerebellum, and olfactory tubercle of na?ve rats. Ethanol challenge produced an attenuated elevation of DOC in rat plasma and brain following chronic ethanol consumption for 2 weeks. These findings suggest that acute ethanol increases DOC levels in ethanol na?ve rats and chronic ethanol consumption induces tolerance to ethanol-induced increases in DOC levels.     

Genetic differences in hypothalamic-pituitary-adrenal axis responsiveness to acute ethanol and acute ethanol withdrawal

There is a growing body of evidence suggesting that corticosteroids contribute to the increased neural excitability observed during ethanol withdrawal. In the present study, this was further investigated using mouse strains which differ in ethanol withdrawal severity. DBA/2 (DBA) mice were found to display more severe acute ethanol withdrawal seizures than C57BL/6 (C57) mice. Additionally, DBA mice showed a greater stress response than C57 mice, as measured by higher plasma concentrations of adrenocorticotropic hormone (ACTH) and corticosterone, to an acute dose of ethanol. Mimicking withdrawal plasma corticosterone levels by administering corticosterone to ethanol-naive mice resulted in increases in handling-induced convulsions in the range observed during withdrawal. There did not appear to be a strain difference in sensitivity to the excitatory effects of corticosterone. In summary, the greater stress response to ethanol by DBA mice may account, in part, for the more severe ethanol withdrawal syndrome of this strain.     

Chronic ethanol exposure during adolescence alters the behavioral responsiveness to ethanol in adult mice

Alcohol exposure during early adolescence is believed to durably alter the behavioral properties of ethanol, increasing the likelihood of later alcohol-related disorders. The aim of the present experiments was to characterize changes in the behavioral effects of ethanol in adult female Swiss mice after a chronic ethanol exposure during adolescence, extending from postnatal day 28 to postnatal day 42. After a chronic ethanol exposure during adolescence (daily injections of 0, 2.5 or 4 g/kg ethanol for 14 consecutive days), adult mice were tested at postnatal day 63. The locomotor stimulant effects of ethanol, together with ethanol sensitization were tested in experiment 1. In experiment 2, the sedative effects of ethanol were assessed with the loss of righting reflex procedure. Finally, in experiment 3, the anxiolytic effects of ethanol were tested with the light/dark box test. Adult mice chronically exposed to ethanol during adolescence showed a lower basal locomotor activity, but higher locomotor stimulant effects of ethanol than non-exposed mice. Additionally, these adult mice developed higher rates of ethanol sensitization after chronic re-exposure to ethanol in adulthood. Adult mice exposed to ethanol during adolescence also had a stronger tolerance to the sedative effects of high ethanol doses, although they showed no evidence of changes in the anxiolytic effects of ethanol. These results are in agreement with the thesis that chronic alcohol consumption during adolescence, especially in high amounts, increases the risk of later alcohol-related disorders.     

Delirium-associated disulfiram and ethanol interactions

Background: Disulfiram, an agent used for the treatment of alcohol dependence, can exacerbate psychiatric syndromes (including psychosis, catatonia, delirium, depression, and mania) after extended use. However, delirium has yet to be reported following the short-term use of disulfiram in the setting of alcohol use. Objectives: We report a case with a neuropsychiatric presentation and discuss the prevention and the progression of delirium associated with an interaction of disulfiram and ethanol. Case Report: We report the case of a 51-year-old woman who developed disorganized speech, diminished communication, a decrease in appetite, and thoughts of suicide 10 days after she began taking disulfiram (250 mg/day), to which she added 1 glass of alcoholic beverage for 2 days. Delirium developed in association with an interaction between disulfiram and alcohol. The patient met DSM-IV criteria for major depressive disorder, alcohol dependence, and delirium. Discussion: Neuropsychiatric manifestations may develop in association with co-administration of disulfiram and alcohol; timely recognition and treatment are recommended.