Multiphasic effect of morphine on the release of substance P from rat trigeminal nucleus slices.
Multiphasic effect of morphine on the release of substance P from rat trigeminal nucleus slices.
复制标题
吗啡对大鼠三叉神经核切片 P 物质释放的多相作用。
DOI：
10.1016/0006-8993(92)90050-j
复制
发表时间：
1992
期刊：
影响因子：
2.9
通讯作者：
Maixner,W
中科院分区：
文献类型：
--
作者：
Suarez-Roca,H;Abdullah,L;Zuniga,J;Madison,S;Maixner,W
一般认为，吗啡在突触前抑制三叉神经核传入终末释放P物质（SP）。然而，最近的研究提供的证据表明，阿片类药物对SP释放产生抑制和兴奋作用，这是浓度和受体亚型依赖性的。在本研究中，我们研究了广泛的吗啡浓度对K+诱发的SP释放大鼠三叉神经尾侧核片。灌流液中测定免疫反应性SP。吗啡对K+诱发的SP释放产生多相效应，而不影响基础释放。极低纳摩尔浓度（1 nM）抑制释放，较高纳摩尔浓度（100-300 nM）促进释放，低微摩尔浓度（3 μM）抑制释放，较高微摩尔浓度（30 μM）促进释放。这些作用被纳洛酮（30 nM）阿片受体阻断剂消除。因此，吗啡产生一个复杂的双向调节SP释放从TNC这是浓度和可能的受体亚型依赖性。
It is generally accepted that morphine acts presynaptically to inhibit substance P (SP) release from afferent terminals in the trigeminal nucleus. Recent studies, however, provide evidence that opioids produce both inhibitory and excitatory effects on SP release which are concentration- and receptor subtype-dependent. In the present study, we have examined a wide range of morphine concentrations on K+-evoked SP release from rat trigeminal nucleus caudalis slices. Immunoreactive SP was measured in perfusates. Morphine produces multiphasic effects on K+-evoked SP release without affecting basal release. A very low nannomolar concentration (1 nM) suppressed release, higher nanomolar concentrations (100–300 nM) facilitated release, a low micromolar concentration (3 μM) suppressed release, and a higher micromolar concentration (30 μM) facilitated release. These effects were abolished by opioid receptor blockade with naloxone (30 nM). Thus, morphine produces a complex bi-directional modulation of SP release from TNC which is concentration- and possibly receptor subtype-dependent.