目的检测吗啡条件性位置偏爱(conditioned place preference,CPP)重现大鼠伏隔核和血浆中神经甾体水平的变化。方法建立大鼠对吗啡的CPP,CPP消退后用足底电击(footshock)诱发CPP的重现。将大鼠断头取血并取出伏隔核,制备组织匀浆,采用液...目的检测吗啡条件性位置偏爱(conditioned place preference,CPP)重现大鼠伏隔核和血浆中神经甾体水平的变化。方法建立大鼠对吗啡的CPP,CPP消退后用足底电击(footshock)诱发CPP的重现。将大鼠断头取血并取出伏隔核,制备组织匀浆,采用液-液萃取和固相萃取法提取脑组织和血浆中的神经甾体,经衍生化后,采用高效液相色谱-质谱法测定神经甾体含量。结果与对照组相比,重现组大鼠伏隔核中的脱氢表雄酮(dehydroepiandrosterone,DHEA)水平升高50%(P<0.05)。与消退组相比,重现组大鼠伏隔核中的别孕烯醇酮(allopregnanolone,AP)水平升高75%(P<0.05);吗啡CPP重现组大鼠血浆中的脱氢表雄酮硫酸酯(dehydroepiandrosterone sulfate,DHEAS)水平下降33%(P<0.01)。结论足底电击应激所致的CPP重现时,大鼠伏隔核中的DHEA,AP和DHEAS水平的变化不依赖于外周血中相应甾体水平的变化,其中枢作用可能与应激诱发的吗啡CPP重现行为有关。足底电击使伏隔核DHEA和AP水平升高可能是应激诱发吗啡CPP重现的神经机制之一。展开更多
There has been an increasing importance of studies that link sex to stress coping processes. Recently, we reported that male and female Wistar rats responded differently to prenatal stress (PS) under basal conditions....There has been an increasing importance of studies that link sex to stress coping processes. Recently, we reported that male and female Wistar rats responded differently to prenatal stress (PS) under basal conditions. The aim of the present study was to determine the influence of sex on behaviour and coping strategies, as an effect of gestational adversity in rats that were exposed to an uncontrollable stressor. Once the animals reached adulthood, the offspring from stressed/non-stressed dams were subjected or not to antidepressant treatment with Sertraline. After that, they were exposed to a single inescapable shock (IS) session, in which the rats were further tested for escape behaviour along 10 days, as a model of learned helplessness (LH). In prenatally stressed animals after the IS, behavioural differences appeared in a sex specific manner. Males proved to be more susceptible to the adverse context than females, exhibiting behavioural despair in a large percentage of the cases. Surprisingly, PS did not affect shock escape failure, but did affect learning performance in a sex dependent manner. In females, PS led them to learn to avoid shocks, learning better than controls, and by contrast, PS males did not learn to avoid shocks and displayed some signs of anhedonia. Sertraline did not help animals to avoid shocks, but helped them to escape from it. Our data indicate the existence of sex dependent behavioural differences in PS animals when facing an uncontrollable stress situation, in which the changes induced by PS were not only different, but opposite between sexes.展开更多
本工作以改进的足底电击应激箱造成大鼠应激,用压脚法测痛,在应激后30min 内观察了54只大鼠的心理应激镇痛(SIA)现象。实验设计了可逃避与不可逃避2种刺激情境,并分别应用安定,以观察刺激的可逃避性和安定对 SIA 的影响。结果表明:足底...本工作以改进的足底电击应激箱造成大鼠应激,用压脚法测痛,在应激后30min 内观察了54只大鼠的心理应激镇痛(SIA)现象。实验设计了可逃避与不可逃避2种刺激情境,并分别应用安定,以观察刺激的可逃避性和安定对 SIA 的影响。结果表明:足底电击导致了明显的 SIA;处于不可逃避情境中的大鼠产生了强于可逃避组的 SIA;安定对可逃避组 SIA 抑制作用显著。结果提示了对刺激情境的认知在 SIA 现象产生中的重要作用,并有助于痛觉心理学和生理心理学实验研究工作的开展和临床疼痛问题的解决。展开更多
文摘目的检测吗啡条件性位置偏爱(conditioned place preference,CPP)重现大鼠伏隔核和血浆中神经甾体水平的变化。方法建立大鼠对吗啡的CPP,CPP消退后用足底电击(footshock)诱发CPP的重现。将大鼠断头取血并取出伏隔核,制备组织匀浆,采用液-液萃取和固相萃取法提取脑组织和血浆中的神经甾体,经衍生化后,采用高效液相色谱-质谱法测定神经甾体含量。结果与对照组相比,重现组大鼠伏隔核中的脱氢表雄酮(dehydroepiandrosterone,DHEA)水平升高50%(P<0.05)。与消退组相比,重现组大鼠伏隔核中的别孕烯醇酮(allopregnanolone,AP)水平升高75%(P<0.05);吗啡CPP重现组大鼠血浆中的脱氢表雄酮硫酸酯(dehydroepiandrosterone sulfate,DHEAS)水平下降33%(P<0.01)。结论足底电击应激所致的CPP重现时,大鼠伏隔核中的DHEA,AP和DHEAS水平的变化不依赖于外周血中相应甾体水平的变化,其中枢作用可能与应激诱发的吗啡CPP重现行为有关。足底电击使伏隔核DHEA和AP水平升高可能是应激诱发吗啡CPP重现的神经机制之一。
文摘There has been an increasing importance of studies that link sex to stress coping processes. Recently, we reported that male and female Wistar rats responded differently to prenatal stress (PS) under basal conditions. The aim of the present study was to determine the influence of sex on behaviour and coping strategies, as an effect of gestational adversity in rats that were exposed to an uncontrollable stressor. Once the animals reached adulthood, the offspring from stressed/non-stressed dams were subjected or not to antidepressant treatment with Sertraline. After that, they were exposed to a single inescapable shock (IS) session, in which the rats were further tested for escape behaviour along 10 days, as a model of learned helplessness (LH). In prenatally stressed animals after the IS, behavioural differences appeared in a sex specific manner. Males proved to be more susceptible to the adverse context than females, exhibiting behavioural despair in a large percentage of the cases. Surprisingly, PS did not affect shock escape failure, but did affect learning performance in a sex dependent manner. In females, PS led them to learn to avoid shocks, learning better than controls, and by contrast, PS males did not learn to avoid shocks and displayed some signs of anhedonia. Sertraline did not help animals to avoid shocks, but helped them to escape from it. Our data indicate the existence of sex dependent behavioural differences in PS animals when facing an uncontrollable stress situation, in which the changes induced by PS were not only different, but opposite between sexes.
文摘本工作以改进的足底电击应激箱造成大鼠应激,用压脚法测痛,在应激后30min 内观察了54只大鼠的心理应激镇痛(SIA)现象。实验设计了可逃避与不可逃避2种刺激情境,并分别应用安定,以观察刺激的可逃避性和安定对 SIA 的影响。结果表明:足底电击导致了明显的 SIA;处于不可逃避情境中的大鼠产生了强于可逃避组的 SIA;安定对可逃避组 SIA 抑制作用显著。结果提示了对刺激情境的认知在 SIA 现象产生中的重要作用,并有助于痛觉心理学和生理心理学实验研究工作的开展和临床疼痛问题的解决。
