Properties of tachykinin receptors examined by intracellular recording from chick sympathetic ganglia.
Properties of tachykinin receptors examined by intracellular recording from chick sympathetic ganglia.
复制标题
通过小鸡交感神经节的细胞内记录检查速激肽受体的特性。
DOI：
10.1016/0006-8993(87)90003-5
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发表时间：
1987
期刊：
影响因子：
2.9
通讯作者：
Chiappinelli,VA
中科院分区：
文献类型：
--
作者：
Ramirez,OA;Chiappinelli,VA
用离体鸡腰交感神经节细胞内记录法研究了速激肽受体的生理和药理学特性。在这些神经节中，P物质和eledoisin都是有效的激动剂，在神经节神经元中产生缓慢发展的去极化与输入电阻的增加和M电流的抑制有关。相比之下，在鸡神经节中，毒蜥毒蛋白是一种效力相当低的速激肽，而kassinin即使在高剂量下也没有活性。速激肽激动剂效力的等级顺序在细胞与细胞之间是一致的，表明单一类型的速激肽受体可能负责观察到的反应。一种假定的速激肽拮抗剂，（d-Arg 1，d-Pro 2，d-Trp 7，9，Leu 11）-P物质，在神经节中没有表现出内在活性，但确实阻断了对随后应用的P物质和eledoisin的反应。这种速激肽拮抗剂还抑制由重复神经刺激在神经节神经元中引起的慢兴奋性突触后电位（EPSP）的一部分。由于已在神经节中的神经纤维内鉴定出P物质，因此似乎这种或另一种内源性速激肽介导了在神经节中观察到的慢EPSP的一部分。通过毒蕈碱受体起作用的乙酰胆碱也能够在神经节中产生缓慢的EPSP，因为用阿托品灌注可以减少一些缓慢的EPSP的大小。它的结论是，鸡交感神经元含有速激肽和毒蕈碱受体，这些受体参与缓慢的突触反应的神经节神经元，增加了细胞的兴奋性。
The physiological and pharmacological properties of tachykinin receptors have been examined by intracellular recording from intact chick lumbar sympathetic ganglia in vitro. In these ganglia, both substance P and eledoisin are potent agonists, producing a slowly developing depolarization in ganglion neurons is associated with an increase in input resistance and inhibition of the M-current. In contrast, physalaemin is a considerably less potent tachykinin in chick ganglia, and kassinin is without activity even at high doses. The rank order of potencies of tachykinin agonists is consistent from cell to cell, indicating that a single type of tachykinin receptor may be responsible for the observed responses. A putative tachykinin antagonist, (d-Arg1,d-Pro2,d-Trp7,9,Leu11)-substance P, exhibits no intrinsic activity in the ganglia but does block the responses to subsequently applied substance P and eledoisin. This tachykinin antagonist also inhibits a portion of the slow excitatory postsynaptic potential (EPSP) elicited in ganglion neurons by repetitive nerve stimulation. Since substance P has been identified within nerve fibers in the ganglia, it appears that this or another endogenous tachykinin mediates a portion of the slow EPSPs observed in the ganglia. Acetylcholine acting via muscarinic receptors is also capable of producing slow EPSPs in the ganglia, since perfusion with atropine can reduce the size of some slow EPSPs. It is concluded that chick sympathetic neurons contain both tachykinin and muscarinic receptors, and that these receptors are involved in slow synaptic responses in the ganglion neurons which increase the excitability of the cells.