CENTRAL NEURONAL PATHWAYS AND THE PROCESS OF ANESTHESIA
CENTRAL NEURONAL PATHWAYS AND THE PROCESS OF ANESTHESIA
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DOI：
10.1093/bja/71.1.148
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发表时间：
1993-07-01
影响因子：
9.8
通讯作者：
ANGEL, A
中科院分区：
文献类型：
--
作者：
ANGEL, A
麻醉剂的作用是复杂的。当给予人类时，它们产生：（a）意识经验的丧失和到达大脑地幔的信息量的减少，如通过对感觉刺激的诱发反应所测量的;（B）记忆的丧失;（c）从头皮记录的自发活动的变化（脑电图（EEG））或直接从皮层表面（皮层脑电图（ECoG））;（d）骨骼肌组织意志控制丧失;（e）保护性反射减弱（反射退缩、咳嗽和呕吐反射）;（f）姿势反射丧失;和（g）心血管和呼吸功能的广泛变化。作为一种实验工具，麻醉可以通过适当选择麻醉剂来设计，以增强、抑制或保持人们希望研究的各种生理变量不变。例如，分别使用巴比妥酸盐和氨基甲酸乙酯可以增强或抑制突触前抑制[13]，并且在用氯醛糖麻醉的动物中可以保留复杂的多感觉异节段反射。大多数生物活性化学品通常的结构-活性关系在麻醉剂中不存在。分子结构的范围很广，从简单的化学物质，如一氧化二氮，到复杂的类固醇，如阿法沙龙，在适当的条件下，可能导致麻醉状态。虽然在解释和行为意义上，麻醉剂可以被例如惊厥性化学物质拮抗，但唯一有效的拮抗剂是非常大的环境压力。压力对麻醉的拮抗作用不是通过特定的阻断化学物质与受体位点竞争的拮抗作用，而是对麻醉剂的物理化学屏障，与假定的疏水受体位点相互作用。简单地看，麻醉剂与其假定作用部位之间的相互作用导致体积增加;增加环境压力可以防止这种体积增加。
The effects of anaesthetic agents are complex. When administered to humans they produce:(a) loss of conscious experience and a decrease in the amount of information which reaches the cerebral mantle, as measured by evoked responses to sensory stimulation;(b) loss of memory;(c) changes in the spontaneous activity recorded from the scalp (electroencephalogram (EEG)) or directly from the cortical surface (electrocorticogram (ECoG));(d) loss of volitional control of the skeletal musculature;(e) an attenuation of protective reflexes (reflex withdrawal, cough and gag reflexes);(f) loss of postural reflexes; and (g) wide ranging changes in cardiovascular and respiratory performance. As an experimental tool, anaesthesia may be designed, by appropriate choice of anaesthetic, to either enhance, suppress or leave unchanged various physiological variables which one wishes to study. For example, presynaptic inhibition may be enhanced or suppressed using barbiturates and urethane, respectively [13] and complex polysensory heterosegmental reflexes may be retained in animals anaesthetized with chloralose. The usual structure-activity relationship seen with most bioactive chemicals is absent in anaesthetics. There is a wide range in molecular structures, ranging from simple chemicals, such as nitrous oxide, to the complex steroids, such as alphaxalone which may, under appropriate conditions, lead to a state of anaesthesia. Although in an interpretational and behavioural sense, anaesthetics may be antagonized by for example, convulsant chemicals, the only effective antagonist is very great ambient pressure. The antagonism of anaesthesia by pressure is not an antagonistic effect of competition with a receptor site by a specific blocking chemical, but a physicochemical barrier to an anaesthetic, interacting with a putative hydrophobic receptor site. Looked at simplistically, the interaction between an anaesthetic and its putative site of action causes an increase in volume; increasing the ambient pressure prevents this volume increase.