脊髓手术中体感诱发电位监测的临床研究

报告３０例脊髓手术中体感诱发电位（ＳＥＰ）连续监测的临床研究结果。ＳＥＰ记录包括脊髓ＳＥＰ（ＳＳＥＰ）和皮层ＳＥＰ（ＳＣＥＰ）。麻醉药物对ＳＥＰ有一定程度影响，ＳＣＥＰ相对较大。认为，至少术中ＳＥＰ潜伏期延长不超过８％和波幅降低不超过５０％，不会引起术后并发症，超过该范围由于病例较少，尚不能肯定与预后的关系，需进一步探讨。     

Rapid effect of stress concentration corticosterone on glutamate receptor and its subtype NMDA receptor activity in cultured hippocampal neurons

Objective: To study the rapid effect of glucocorticoids (GCs) on NMDA receptor activity in hippocampal neurons in stress and to elucidate its underlying probable membrane mechanisms. Methods: Whole-cell patch-clamp recording was used to assess the effect of stress concentration corticosterone (B) on the responses of cultured hippocampal neurons to glutamate and NMDA (N-methy-D-asparatic acid). To make clear the target of B, intracellular dialysis of B(10μmol/L)through patch pipette and extracellular application of bovine serum albumin-conjugated corticosterone (B-BSA, 10μmol/L)were carried out to observe their influence on peak amplitude of NMDA-evoked current. Results: B had a rapid, reversible and inhibitory effect on peak amplitude of GLU-or NMDA-evoked current in cultured hippoeampal neurons. Furthermore, B-BSA had the inhibitory effect on INMDA as that of B, but intraeeUularly dialyzed B had no significant effect on INMDA. Conclusion: These results suggest that under the condition of stress, GCs may rapidly, negatively regulate excitatory synaptic receptors-glutamate receptors (GluRs), especially NMDA receptor (NMDAR) in central nervous system, which is mediated by rapid membrane mechanisms, but not by classical, genomic mechanisms.     

Rapid tolerance against focal cerebral ischemia induced by isoflurane anesthesia is attenuated by adenosine A1 receptor antagonist in rats

The brief anesthesia with isoflurane induces rapid tolerance against focal cerebral ischemia in rats and aden-osine A1 receptor antagonist, DPCPX, attenuates the beneficial effect of isoflurane preconditioning.     

Sparing of perceptual implicit memory despite suppression of the electrophysiological word repetition effect: a study with general anesthetic isoflurane.

OBJECTIVE: Much effort has been devoted to the search for the neurophysiological correlates of implicit memory. A commonly held view is that the early portion (250-500 ms) of the event-related potential (ERP) word repetition effect reflects processes important for perceptual implicit memory whereas the latter portion reflects processes implicated in explicit memory. It is, however, difficult to disentangle with certainty the relative contributions of each form of memory on ERPs since both forms co-exist in normal subjects. To dissociate ERP effect related to implicit and explicit memory, we used isoflurane sedation in normal subjects to suppress explicit remembering while sparing implicit memory. These ERPs were compared with those of non-medicated control subjects. METHODS: Thirteen subjects performed an incidental encoding task for words presented auditorily during the inhalation of a subanesthetic dose of isoflurane. After termination of isoflurane administration, we assessed free recall and recorded ERPs during a syllable completion task (implicit memory) and during a passive listening task (ERP repetition effect). Eleven non-medicated control subjects were tested in a similar manner. RESULTS: The controls showed robust early and late ERP repetition effect. The isoflurane group had implicit memory without free recall and showed no ERP repetition effect. CONCLUSIONS: These findings failed to show an association between any part of the repetition effect and perceptual implicit memory. The results are consistent with the view that processes linked to explicit memory contribute to the ERP repetition effect since there was a marked difference in free recall between the control and isoflurane groups. SIGNIFICANCE: The present study shows that the reversible alterations of memory by general anesthetics can be used to study the neurophysiological correlates of memory processes.     

缺血性脑血管病患者血清基质金属蛋白酶水平及影响因素分析

目的 比较急性脑梗死、短暂脑缺血发作(TIA)和陈旧脑梗死患者血清基质金属蛋白酶-9(MMP-9)水平并分析其影响因素.方法 缺血性脑血管病患者136例,分为急性脑梗死组57例,TIA组22例,陈旧脑梗死组57例,进行神经功能评分及血压、血常规、血脂、血糖检查.依据ELISA法进行血MMP-9测定.结果 MMP-9水平分别为急性脑梗死患者(444.13±418.46)ng/ml,TIA患者(374.36±278.31)ng/ml,陈旧脑梗死患者(231.11±367.43)ng/ml.急性脑梗死和TIA患者血MMP-9水平明显高于陈旧脑梗死患者(P＜0.05).MMP-9水平与血白细胞水平(r=0.192,P=0.025)、低密度脂蛋白(r=0.261,P=0.002)、收缩压(r=0.232,P=0.006)呈正相关;与高密度脂蛋白(r=-0.219,P=0.011)和血糖(r=-0.254,P=0.003)呈负相关.MMP-9与收缩压(β=0.259,P=0.001)、血白细胞(β=0.209,P=0.008)、低密度脂蛋白(β=0.586,P=0.000)、胆固醇(β=-0.458,P=0.007)和血糖(β=-0.200,P=0.014)具有线性关系.结论 MMP-9水平在急性脑梗死及TIA时升高,收缩压、血白细胞和低密度脂蛋白均可能为其影响因素.     

高原低氧对大鼠学习记忆影响的实验研究

目的：研究高原低氧环境对大鼠学习记忆的影响。方法：利用新生大鼠低氧模型和胎鼠低氧模型，采用爬杆实验和Morris水迷宫实验进行检测.结果：爬杆实验中习得的速度减慢，消退速度加快。Morris水迷宫实验中逃避潜伏期延长，撤除平台后跨越平台次数减少。结论：高原低氧环境下大鼠的学习记忆能力受到抑制，可能与长期低氧后海马NMDA受体数量和功能的下降有关。