摘要：

The purpose of the present paper is to compare the neurophysiological actions of gamma-hydroxybutyrate (GHB) with pentobarbital in cats with chronically implanted electrodes. Observations were performed on gross behavior, EEG activity and averaged response to clicks. The major behavioral and EEG effects following GHB are as follows: 60 mg/kg - no perceptible differences; 100–200 mg/kg - animal crouched, pupils dilated, head elevated, hypersalivates and occasionally vomits during spindling EEG pattern; 200–600 mg/kg - intermittent hypersynchronous bursts, posture unchanged, the electrical activity shifts to continuous hypersynchronous 2.5 c/sec waves; 400–600 mg/kg - spiking initially more pronounced in limbic leads while the hypersynchrony slows to 1.5 c/sec in other leads, followed by generalized high amplitude spikes and short polyphasic bursts with short periods of electrical silence between spikes in all leads. There are periods of spontaneous myoclonic jerks which are intensified by stimuli. Averaged evoked responses in the ASG, MBRF and CL increase in amplitude as the dose of GHB is increased. In contrast to GHB, pentobarbital (40 mg/kg) produces an initial desynchronization with ataxia, spindling and burst suppression phase. The averaged evoked responses to click gradually reduce in amplitude during these corresponding phases. On the basis of gross behavior, EEG patterns and averaged evoked response to clicks it appears that GHB and pentobarbital do not have similar properties. The action of GHB is similar to generalized non-convulsant epilepsy. It is proposed that the clinical efficacy of this agent may be based on the induction of a lack of responsiveness rather than by virtue of specific anesthetic properties. A re-evaluation of the desirable properties of anesthetic agents and the anesthetic state seems in order as a result of the apparent clinical success which GHB has had as an anesthetic agent.

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