Durham H D, Frank G B
Arch Int Pharmacodyn Ther. 1981 May;251(1):150-65.
The action of meperidine was investigated on the frog sciatic nerve-sartorius muscle in vitro. Meperidine (5 X 10(-5) M to 2 X 10(-4) M) depressed the twitch response to nerve stimulation but potentiated the response to direct muscle stimulation. When the nerve terminal action potential and the endplate potential (EPP) were recorded simultaneously, the EPP was depressed by meperidine but only a small and variable decrease in the nerve terminal action potential was observed which did not produce the EPP depression. The depression of the EPP was partly antagonized by naloxone (3 X 10(-8) M). Meperidine also depressed the EPP produced by iontophoresis of acetylcholine onto the endplate, but this depression was not antagonized by naloxone. It is concluded that there are two meperidine actions on junctional transmission in this preparation. One, a depression of the prejunctional transmitter release process. This depression is partly, if not completely, opiate receptor-mediated. The second is a depression of the response of the endplate to acetylcholine. The latter effect does not involve a naloxone-sensitive opiate receptor.
在体外对青蛙坐骨神经 - 缝匠肌研究了哌替啶的作用。哌替啶（5×10⁻⁵M至2×10⁻⁴M）抑制对神经刺激的抽搐反应，但增强对直接肌肉刺激的反应。当同时记录神经末梢动作电位和终板电位（EPP）时，哌替啶使EPP降低，但仅观察到神经末梢动作电位有小的且可变的降低，这并未引起EPP降低。EPP的降低部分被纳洛酮（3×10⁻⁸M）拮抗。哌替啶也抑制通过将乙酰胆碱离子导入终板产生的EPP，但这种抑制未被纳洛酮拮抗。得出结论，在该制剂中哌替啶对突触传递有两种作用。一种是抑制突触前递质释放过程。这种抑制部分（如果不是完全）由阿片受体介导。第二种是抑制终板对乙酰胆碱的反应。后一种效应不涉及对纳洛酮敏感的阿片受体。
