Vinogradova O S, Brazhnik E S, Stafekhina V S, Kichigina V F
Zh Vyssh Nerv Deiat Im I P Pavlova. 1994 Nov-Dec;44(6):1026-37.
Cholinergic modulation of the single-cell responses and field potentials evoked in the hippocampus by electrical stimulation of its cortical input was investigated in two groups of chronic anaesthetized rabbits--with the intact septum (IS) and basally undercut (BS). In both groups of animals responses to stimulation of the perforant path (PP) or mossy fibers were blocked or significantly suppressed in substantial proportion of the neurons (50% in IS, 69% in BS) by i.v. physostigmine injection; facilitation of responses was observed in minor groups of the neurons (10% and 8%). Scopolamine restored initial responsiveness of the hippocampal neurons and augmented responses to stimulation in some of them (37.5% in IS, 65% in BS). Effect of physostigmine was reproduced by single stimuli applied to the MS--DB. Field potentials evoked by PP stimulation in CA of IS group were equally suppressed (by 43%) by the sensory stimulation evoking natural theta, by physostigmine and MS--DB stimulation. In BS group of animals these influences completely suppressed the focal potentials to PP stimulation. Scopolamine restored the focal potentials. It is concluded that the main function of the septo-hippocampal cholinergic input consists in filtering out the signals appearing at the background of the theta-rhythm triggered by a previous signal thus preventing their interference with its processing and recording.
在两组慢性麻醉兔中研究了通过电刺激其皮质输入在海马中诱发的单细胞反应和场电位的胆碱能调制，一组兔保留完整的隔区（IS），另一组兔进行基底切断（BS）。在两组动物中，静脉注射毒扁豆碱后，相当比例的神经元（IS组为50%，BS组为69%）对穿通通路（PP）或苔藓纤维刺激的反应被阻断或显著抑制；在少数神经元组中观察到反应增强（分别为10%和8%）。东莨菪碱恢复了海马神经元的初始反应性，并增强了其中一些神经元对刺激的反应（IS组为37.5%，BS组为65%）。对内侧隔核-斜角带核（MS-DB）施加单个刺激可重现毒扁豆碱的作用。在IS组的CA区，由PP刺激诱发的场电位被诱发自然θ节律的感觉刺激、毒扁豆碱和MS-DB刺激同样抑制（抑制43%）。在BS组动物中，这些影响完全抑制了对PP刺激的局灶性电位。东莨菪碱恢复了局灶性电位。得出的结论是，隔区-海马胆碱能输入的主要功能在于滤除在前一个信号触发的θ节律背景下出现的信号，从而防止它们干扰其处理和记录。
