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E Forney

Publications and source records attributed to E Forney.

5 recordsLinked to original sources
PubMed1976

Differential effects of low doses of ethanol on the impulse activity in various regions of the limbic system.

This study was a follow-up to our earlier data which indicated that the hippocampus was one of the brain areas in which ethanol had a preferential action. Rabbits were chronically implanted with electrodes in 9 brain areas associated with the hippocampus. The EEG and multiple-unit activity were recorded simultaneously in each area before and for 15 min after i.p. injection of ethanol at dosages of 0, 150, 300, or 600 mg/kg, given in random order. Subjective evaluation of EEG tracings from all brain areas did not disclose any regional differences. The incidence of hippocampal theta rhythm was depressed transiently at the 2 lower doses and was increased in some rabbits at later post-injection times after the largest dose. Quantitative analysis of the unit activity revealed several major effects of ethanol. Individual rabbits varied significantly in their degree of response. The effects of ethanol included phasic decreases and increases, which varied with the brain area and the dose. A predominant depression of MUA occurred in the septum, fimbria/fornix, entorhinal cortex, and CA1 zone of the hippocampus. Large transient increases in MUA were noted in the CA1, hippocampal commissure, and entorhinal cortex. Overall, regional differences in unit activity consisted of a relatively greater effect in the septum, CA1, and the entorhinal cortex. Conspicuously smaller effects were evident in the CA3 and dentate zones of the hippocampus.

Animals↗
PubMed1976

Ethanol-induced regional and dose-response differences in multiple-unit activity in rabbits.

Multiple-unit activity (MUA), recorded simultaneously from many brain areas, was used to detect the existence ahd location of "target sites" for ethanol action in rabbits with chronically implanted electrodes in 14 areas. Each of 12 rabbits received intraperitoneal injection of 300, 600, 900, and 1200 mg/kg of 20% ETOH and a saline control injection given in random order with at least a 4-day interval between injections. Large amounts of MUA data, recorded continuously for a 2-min pre-injection control period and a 15-min post-injection period, were quantified by a sensitive and unique technique. MUA changes did not correlate with alcohol-induced changes in the corresponding EEG for the same locus. Whereas visual inspection of the EEG did not disclose any regional differences in response to ethanol, both temporal and topographical differences in ethanol effect on MUA were observed. There were 14 histologically verified brain areas with adequate sample size for statistical evaluation of MUA response. At high doses, all brain areas were affected. Included among the brain areas which were least affected by low doseas were the caudate nucleus, septum, fornix, and medial forebrain bundle. Those areas that met the criteria for target sites of responding quickly (less than 5 min) to low doses (300 mg/kg) were: cerebellar cortex, cerebral cortex, hippocampus, lateral and medial geniculate nuclei, midbrain reticular formation, and pyriform cortex. In conjunction with the preliminary study [Brain Res. 70, 361 (1974], the data indicate that the most ethanolsensitive tissue is found in the various kinds of cortex, cerebellar and cerebral (both paleocortex and neocortex).

Animals↗
PubMed1976

Effect of ethanol on impulse activity in isolated cerebellum.

We tested the question of whether ethanol's known action on the cerebellum is direct or indirect, via neural pathways. The cerebellum of rats was denervated by large electrolytic lesions of the peduncles. Ethanol (1 gm/kg, intraperitoneally injected) generally depressed impulse activity of neuronal populations in the cerebellar cortex, whereas such activity increased in saline-injected controls.

Animals↗