Transient and prolonged effects of acetylcholine on responsiveness of cat somatosensory cortical neurons.
Transient and prolonged effects of acetylcholine on responsiveness of cat somatosensory cortical neurons.
复制标题
乙酰胆碱对猫体感皮层神经元反应性的短暂和长期影响。
DOI：
10.1152/jn.1988.59.4.1253
复制
发表时间：
1988
影响因子：
2.5
通讯作者：
Dykes,RW
中科院分区：
文献类型：
--
作者：
Metherate,R;Tremblay,N;Dykes,RW
1. 在巴比妥酸麻醉的猫中，研究了277个神经元在给乙酰胆碱（ACh）离子吸氧时的反应性变化。2. 确定了78个细胞的层状位置。胆碱感觉神经元分布于所有皮质层，第一层占50%，第六层占78%。当通过固定剂量谷氨酸产生的放电强度来测量神经元的反应性时，47例中有30例（64%）在谷氨酸诱导的兴奋中给予ACh时增强，4例（8%）抑制。4. 谷氨酸兴奋时给予乙酰胆碱比单独给予乙酰胆碱更有效地改变神经元的反应性（P < 0.001）。5. 当通过施加于感受野的标准体细胞刺激产生的放电强度来测量神经元的反应性时，52例中有42例（81%）在施加乙酰胆碱时增强。这再次不同于单独的乙酰胆碱治疗，27次试验中只有4次（15%）导致对躯体刺激的反应增强。6. 乙酰胆碱通常增加具有外周感受野的神经元的反应性，并在一些缺乏感受野的细胞中引起感受野的出现。7. 在许多情况下，兴奋性的变化，通过对谷氨酸或躯体刺激的反应来测量，会持续很长时间。当使用谷氨酸测试兴奋性时，34%（47个中的16个）的增强持续超过5分钟。当使用躯体刺激时，29%（52人中15人）持续时间超过5分钟。在这两种方法下，一些神经元在乙酰胆碱处理1小时后仍表现出增强的反应。8. 乙酰胆碱似乎作为一种许可剂，允许修改先前存在的传入输入驱动体感觉皮质神经元的有效性。9. 这种改变神经元反应的机制具有许多必要的特征，可以解释在传入驱动改变后在体感觉皮层中观察到的重组，并可能与某些形式的学习和记忆有关。
1. Two-hundred and seven neurons were examined for changes in their responsiveness during the iontophoretic administration of acetylcholine (ACh) in barbiturate-anesthetized cats. 2. The laminar locations of 78 cells were determined. Cholinoceptive neurons were found in all cortical layers and ranged from 50% of the cells tested in layer I to 78% in layer VI. 3. When the responsiveness of a neuron was measured by the magnitude of the discharge generated by a fixed dose of glutamate, 30 of 47 cases (64%) were potentiated, and 4 (8%) were depressed when ACh was administered during glutamate-induced excitation. 4. ACh administered during glutamate excitation was significantly more effective in altering neuronal responsiveness than was ACh administered alone (P less than 0.001). 5. When the responsiveness of a neuron was measured by the magnitude of the discharge generated by a standard somatic stimulus applied to the receptive field, 42 of 52 cases (81%) were potentiated during ACh application. This was again different from ACh treatment alone where only 4 of 27 tests (15%) resulted in subsequent enhancement of the response to somatic stimuli. 6. ACh generally increased the responsiveness of neurons with peripheral receptive fields and caused the appearance of a receptive field in some cells lacking one. 7. In many cases the changes in excitability, as measured by responses either to glutamate or to somatic stimulation, remained for prolonged time periods. When glutamate was used to test excitability, 34% (16 of 47) of the enhancements lasted more than 5 min. When somatic stimuli were used 29% (15 of 52) lasted more than 5 min. With both measures some neurons still displayed enhanced responses more than 1 h after the treatment with ACh. 8. ACh appears to act as a permissive agent that allows modification of the effectiveness with which previously existing afferent inputs drive somatosensory cortical neurons. 9. This mechanism to alter neuronal responsiveness has many of the characteristics necessary to account for the reorganization observed in somatosensory cortex following alterations in its afferent drive and may be related to some forms of learning and memory.