Hanani M, Chorev M, Gilon C, Selinger Z
Laboratory of Experimental Surgery, Hadassah University Hospital, Mt. Scopus, Jerusalem, Israel.
Eur J Pharmacol. 1988 Aug 24;153(2-3):247-53. doi: 10.1016/0014-2999(88)90612-7.
Intracellular recordings were made from myenteric neurons of the guinea-pig duodenum and the responses to local ejection of several substance P (SP) analogs were examined. It was found that senktide (succinyl-[Asp6,Me-Phe8]SP-(6-11)), a selective analog for the NK-3 (SP-N) receptor, was particularly effective in depolarizing the neurons. It was 20-100 times more potent than SP and about 1000-fold more potent than the selective analogs for the NK-1 (SP-P) receptor, which resides on muscle cells. The response to the peptides was prolonged (20-120 s), but in about 20% of the cells there was a fast, early depolarizing component (observed only with senktide). In most cases there was an increase in the input resistance of the cell during the slow depolarization. Together with the finding that the response reversed at about -90 mV, this indicates that the response is due to the closure of K+ channels. The results support the existence of an NK-3 (SP-N) receptor and provide direct information about the membrane mechanisms through which NK-3 agonists excite myenteric neurons.
从豚鼠十二指肠的肌间神经丛神经元进行细胞内记录，并检测其对几种P物质（SP）类似物局部喷射的反应。发现senktide（琥珀酰-[天冬氨酸6，甲基苯丙氨酸8]SP-(6-11)），一种NK-3（SP-N）受体的选择性类似物，在使神经元去极化方面特别有效。它的效力比SP强20-100倍，比存在于肌肉细胞上的NK-1（SP-P）受体的选择性类似物强约1000倍。对这些肽的反应持续时间延长（20-120秒），但在约20%的细胞中存在快速、早期去极化成分（仅在senktide作用下观察到）。在大多数情况下，细胞在缓慢去极化过程中输入电阻增加。结合反应在约-90mV时反转这一发现，这表明该反应是由于钾通道的关闭。这些结果支持NK-3（SP-N）受体的存在，并提供了关于NK-3激动剂兴奋肌间神经丛神经元的膜机制的直接信息。
