Muscarine receptor activation in the substantia gelatinosa of the spinal trigeminal nucleus of the guinea pig.
Muscarine receptor activation in the substantia gelatinosa of the spinal trigeminal nucleus of the guinea pig.
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豚鼠脊髓三叉神经核胶质中的毒蕈碱受体激活。
DOI：
10.1152/jn.1996.76.6.3817
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Travagli,RA
中科院分区：
文献类型：
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作者：
Travagli,RA
1.用豚鼠三叉神经脊束核尾侧部（SG）切片进行细胞内记录。2.毒蕈碱[0.3-30 μ M;半数最大有效浓度（EC 50）= 2.9 μ M]使61%的SG神经元超极化。卡巴胆碱（0.3-30 μ M; EC 50 = 3.9 μ M）可模拟该作用，哌仑西平（1 μ M）可拮抗该作用。34%的神经元被毒蕈碱和卡巴胆碱（1-30 μ M：EC 50 = 5.7 μ M）去极化，这种作用被哌仑西平（100 nM）拮抗。3.在大约80%的记录中，毒蕈碱（10-30 μ M）诱发重复的自发抑制性突触后电位（IPSP），对荷包牡丹碱（10 μ M）敏感。4.毒蕈碱（1-30 μ M; EC 50 = 3 μ M）降低了大多数诱发兴奋性突触后电位（EPSP）的振幅，卡巴胆碱模拟了该作用，哌仑西平（100 nM）拮抗了该作用。5.这些结果表明，毒蕈碱抑制SG神经元至少有三种机制：1）通过激活非M1受体的超极化; 2）激活含有γ-氨基丁酸的中间神经元，其介导神经元亚群中的IPSP; 3）降低诱发的EPSP振幅。毒蕈碱还可以通过与M1型受体的相互作用激活SG神经元。
1. Intracellular recordings were made from slices of guinea pig spinal trigeminal nucleus pars caudalis (SG). 2. Muscarine [0.3–30 microM; half maximally effective concentration (EC50) = 2.9 microM] hyperpolarized 61% of SG neurons. The effect was mimicked by carbachol (0.3–30 microM; EC50 = 3.9 microM) and antagonized by pirenzepine (1 microM). Thirty-four percent of the neurons were depolarized by muscarine and carbachol (1–30 microM: EC50 = 5.7 microM), and the effect was antagonized by pirenzepine (100 nM). 3. In approximately 80% of recordings, muscarine (10–30 microM) evoked repetitive spontaneous inhibitory postsynaptic potentials (IPSPs) that were sensitive to bicuculline (10 microM). 4. Muscarine (1–30 microM; EC50 = 3 microM) decreased the amplitude of the majority of evoked excitatory postsynaptic potentials (EPSPs), and the effect was mimicked by carbachol and antagonized by pirenzepine (100 nM). 5. These results indicate that there are at least three mechanisms by which muscarine inhibits SG neurons: 1) hyperpolarization through activation of non-M1 receptors; 2) activation of gamma-amino-butyric acid-containing interneurons that mediate IPSPs in a subset of neurons; and 3) a decrease in evoked EPSP amplitude. Muscarine can also activate SG neurons via interaction with an M1-type receptor.