脑电相关监测指标在缺血性脑卒中患者预后评估中的研究进展

缺血性脑卒中是临床上高发病率、高致残率的疾病之一,对缺血性脑卒中预后的良好评估可为医患沟通、治疗方案调整等方面提供依据。因此,如何提高预后评估的准确性一直是神经病学领域的热点和前沿问题。脑神经功能损伤程度与缺血性脑卒中的预后密切相关已得到共识,脑电图(EEG)可反映脑神经功能损伤的有无及程度。EEG及其衍生指标(如诱发电位、脑电非线性分析)近年来备受关注,具有无创、准确、客观及可重复性强的优点,在临床上已呈现出良好的应用前景。     

丙泊酚对大鼠海马脑片CA1区长时程增强的影响

目的观察不同浓度丙泊酚对离体大鼠海马脑片CA1区长时程增强(LTP)的影响。方法30张海马脑片分为五组,Ⅰ、Ⅱ和Ⅲ组分别应用浓度为30、10和3μmolo/L的丙泊酚,Ⅳ组用脂肪乳,Ⅴ组不用药物作为对照。利用细胞外记录方式,以海马脑片CA1区群峰电位(PS)为观察指标,首先观察丙泊酚对CA1区基础传递的影响,待基线稳定后,记录高频刺激(HFS)后海马脑片CA1区PS的变化情况。结果Ⅰ、Ⅱ、Ⅲ组应用丙泊酚后PS降低,在持续给药后30min恢复至基线。实施HFS后,Ⅲ、Ⅳ和Ⅴ组的PS较HFS前显著升高(P<0.05,P<0.01);而Ⅰ、Ⅱ组PS与HFS前相比差异无显著意义(P>0.05)。HFS后,Ⅰ组PS显著低于Ⅱ、Ⅲ、Ⅳ和Ⅴ组(P<0.01),Ⅱ组PS也低于Ⅲ、Ⅳ和Ⅴ组(P<0.05)。结论丙泊酚可以抑制大鼠离体海马脑片CA1区LTP的形成。     

Na^＋、K^＋—ATP酶及麻醉药对其影响

Na^ 、K^-ATP酶广泛分布于各类细胞质膜上，形成和维持了Na^ 、K^ 在膜内外正常的浓度差，产生并维持细胞膜电位，维持神经细胞的兴奋性和传导性。麻醉药对Na^ 、K^ －ATP酶具有抑制作用。本文综述了Na^ 、K^ -ATP酶的分子结构、分布、生理功能及麻醉药对其影响。     

NMDA受体在痛敏及阿片耐受和依赖中的作用

NMDA受体通过与阿片受体之间的相互作用,介导痛觉过敏以及阿片耐受和依赖的形成和发展,为临床疼痛治 疗和阿片类药物依赖的防治提供了新的思路。     

鞘内注射吗啡加可乐定对切口痛大鼠脊髓背角蛋白激酶A催化亚单位表达的影响

Objective To observe the effect of intrathecal clonidine plus morphine on expression of protein kinase A (PKA) catalytic subunit in the spinal dorsal horn in a rat model of incisional pain. Methods Eighty male Sprague-Dawley rats were divided randomly into five groups: sham group, control group, pre-incisional morphine 2.5 μg group, pro-incisional clonidine 5 μg group and preincisional morphine 2.5 μg plus clonidine 5 lag group (n=16). lntrathecal catheter and the model of incisional pain were pro-duced according to Yaksh and Brennan's described method respectively. Changes of pain behavior were assessed by mechanical with-drawal threshold (MWT) and thermal withdrawal latency(TWL). The expressions of PKA catalytic subunit in the spinal dorsal horn were assessed by immunohistochemical method and western blotting analysis. Results Compared with sham group, MWT and TWL in control group were decreased significantly at 2 h after incision (P<0.01) and the number of positive cells and protein expression of PKA catalytic subunit in the spinal dorsal horn were increased significantly in control group (P<0.01). Compared with control group, MWT and TWL in pre-incision morphine 2 μg plus clonidine 5 lag group were increased significantly at 2 h after incision (P<0.01) and the number of positive cells and protein expression of PKA catalytic subunit in the spinal dorsal horn were decreased significantly in pre-incision morphine 2 μg plus clonidine 5 μg group (P<0.01). However, MWT, TWL and the number of positive cells and pro-tein expression of PKA catalytic subunit in the spinal dorsal horn changed with no statistical significance in pre-incisional morphine 2.5 μg group and pre-incisional clonidine 5 μg group compared with control group. Conclusion lntrathecal clonidine significantly enhances the antinociceptive effect of intrathecal morphine in a rat model of incisional pain, which might be associated with inhibi-tion of the increased expression of PKA catalytic subunit in spinal cord.     

人参皂甙抗离体大鼠心肌缺血再灌注损伤的作用

目的探讨人参皂甙(GS)预处理给药及治疗性给药对离体大鼠心肌缺血再灌注损伤的保护作用的异同。方法采用Langendorff离体心脏灌注模型，分对照组(Con)、GS预处理组(GSp)、GS治疗组(Gst)。以Maclab／4S生理实验系统记录大鼠左心功能指标，包括左心室舒张压(INEDP)、左心室发展压(LVDP)、左心室内压上升最大速率( dp/dtmax)、左心室内压下降最大速率(-dp/dtmax)和心率(HR)的波型和数值；用TIC染色法测定再灌注末左心室心肌梗死面积。结果与对照组相比，GSp组和GSt组均显著提高心功能指数，减少心肌梗死面积：GSp组与GSt组间无差异。结论GS预处理给药及治疗性给药对心肌缺血再灌注损伤均有明显的保护作用，二者心肌保护作用无显著差异。     

鞘内注射吗啡对切口疼痛大鼠脊髓背角蛋白激酶Cγ免疫反应的影响

目的 研究鞘内注射吗啡对切口疼痛大鼠脊髓背角蛋白激酶Cγ(PKCγ)免疫反应的影响。方法 SD雄性大鼠24只,随机分为4组(每组6只):假手术组(Ⅰ组)、对照组(Ⅱ组)术前30 min鞘内注射人工脑脊液20μl,术后吗啡治疗组(Ⅲ组)、术前吗啡治疗组(Ⅳ组)分别于术后和术前30min鞘内注射吗啡5μg(10 μl)。所有大鼠均按Brennan法制成切口疼痛模型,用免疫组织化学方法观察脊髓背角PKCγ的表达。结果 Ⅱ组术侧脊髓背角PKCγ-IR表达高于非术侧及Ⅰ组(P<0.01)。与Ⅱ组比较,Ⅲ组、Ⅳ组脊髓背角PKCγ-IR表达降低(P<0.05或0.01),而Ⅲ组、Ⅳ组比较差异无显著性。结论 在大鼠切口疼痛模型中,鞘内注射吗啡的镇痛作用可能与抑制脊髓背角的PKCγ-IR免疫反应有关。     

NMDA受体与躯体内脏的痛觉调制

NMDA受体是兴奋性氨基酸的特异性受体，与神经细胞钙离子内流密切相关，参与体内各种信号传递和调节神经元的兴奋性。它由不同的亚基组成，这些亚基决定着天然NMDA受体的功能特性，其中，含NR2B亚基的受体对伤害性感受的传递和调制有重要作用。已有大量研究表明，NMDA受体在痛觉中枢敏感化的产生、维持中有重要作用；NMDA受体也可能同时介导外周敏感化和内脏痛。     

挥发性麻醉药后处理保护缺血/再灌注心肌的研究进展

缺血后处理（ischemic postconditioning）是近年来提出的一种新的心肌保护方法，即心肌缺血后在长时间的再灌注之前，进行的数次短暂再灌注／缺血的循环。实验证明后处理对缺血心肌确有显著的保护作用。挥发性麻醉药后处理也可以发挥同样的保护效应，其机制比较复杂，远未阐明，现就其保护作用的机制作一综述。