Fu Y, Guo L, Zhang J, Chen Y, Wang X, Zeng T, Tian S, Ma Y
Chinese Academy of Sciences, Kunming Institute of Zoology, Laboratory of Primate Neuroscience Research and Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming, Yunnan, PR China.
Eur J Anaesthesiol. 2008 Oct;25(10):826-33. doi: 10.1017/S0265021508004687. Epub 2008 Jun 23.
Pentobarbital and ketamine are commonly used in animal experiments, including studies on the effects of ageing on the central nervous system. The electroencephalogram is a sensitive measure of brain activity. The present study investigated, under anaesthesia induced by the two drugs, whether cortical electroencephalogram in aged rats differs from that in young rats.
Electroencephalogram was recorded for young (2-3 months) and aged (15-17 months) rats before and during pentobarbital (40 mg kg (-1))or ketamine (100 mg kg (-1)) anaesthesia. The relative power in five frequency bands (delta: 2-4 Hz; theta: 4-8 Hz; alpha: 8-12 Hz; beta: 12-20 Hz; gamma: 20-100 Hz) was analysed, and then compared between the two age groups.
In both age groups, pentobarbital anaesthesia induced an increase in relative power in alpha and beta bands and a decrease in the theta band, but the degree of these power variations was more marked in aged rats. Ketamine anaesthesia increased relative power in the delta band and decreased that in the theta band; these effects were significantly different between the two age groups, with aged rats showing more markedly decreased power in the theta band.
(a) Pentobarbital and ketamine modified cortical electrical activity in a different manner as a function of age; (b) the modification of electroencephalogram relative power with anaesthesia was identical in young and aged rats but quantitatively more marked in aged rats. These findings will be useful in designing experiments that assess pathological changes in the central nervous system during ageing.
戊巴比妥和氯胺酮常用于动物实验，包括衰老对中枢神经系统影响的研究。脑电图是脑活动的一种敏感测量指标。本研究在这两种药物诱导的麻醉状态下，探究老年大鼠的皮质脑电图是否与年轻大鼠不同。
记录年轻（2 - 3个月）和老年（15 - 17个月）大鼠在戊巴比妥（40 mg kg⁻¹）或氯胺酮（100 mg kg⁻¹）麻醉前及麻醉期间的脑电图。分析五个频段（δ波：2 - 4 Hz；θ波：4 - 8 Hz；α波：8 - 12 Hz；β波：12 - 20 Hz；γ波：20 - 100 Hz）的相对功率，然后在两个年龄组之间进行比较。
在两个年龄组中，戊巴比妥麻醉均导致α波和β波频段的相对功率增加，θ波频段的相对功率降低，但这些功率变化的程度在老年大鼠中更为明显。氯胺酮麻醉使δ波频段的相对功率增加，θ波频段的相对功率降低；这两种效应在两个年龄组之间有显著差异，老年大鼠的θ波频段功率降低更为明显。
（a）戊巴比妥和氯胺酮随年龄增长以不同方式改变皮质电活动；（b）麻醉对脑电图相对功率的改变在年轻和老年大鼠中相同，但在老年大鼠中在数量上更为明显。这些发现将有助于设计评估衰老过程中中枢神经系统病理变化的实验。
