Release of [3H]5-hydroxytryptamine from the intermediate area of rat thoracic spinal cord is modulated by presynaptic autoreceptors.
Release of [3H]5-hydroxytryptamine from the intermediate area of rat thoracic spinal cord is modulated by presynaptic autoreceptors.
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[3H]5-羟色胺从大鼠胸脊髓中间区域的释放受到突触前自身受体的调节。
DOI：
10.1002/syn.890180305
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Helke,CJ
中科院分区：
文献类型：
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作者：
Yang,L;Jacocks3rd,HM;Helke,CJ
5-羟色胺（5-HT）神经末梢支配中间外侧细胞柱（IML）的交感节前神经元;然而，在该系统中既没有直接研究去极化诱导的5-HT释放，也没有直接研究突触前调节性自身受体的存在。我们使用体外灌流大鼠胸髓的显微切割中间区（包括中间外侧细胞柱，闰核和中央自主神经核）来测量预载的[3 H]5-HT的基础和刺激释放。升高的K+诱发[3 H]5-HT的浓度依赖性和Ca 2+依赖性释放。外源性5-HT和5-HT 1拮抗剂CGS-12066 B均降低K+刺激的[3 H]5-HT释放。5-HT 1B拮抗剂（甲硫替平）可阻断5-HT-和CGS-12066 B-诱导的K+-诱发的[3 H]5-HT释放抑制。5-HT 1A拮抗剂（NAN-190）未改变外源性5-HT的抑制作用。此外，5-HT 1A激动剂（8-OH-DPAT）、5-HT 2A/2C激动剂[（+/-）-DOI盐酸盐]和5-HT 3激动剂（2-甲基-5-HT）未改变K+诱发的[3 H]5-HT释放。这些数据表明，5-HT从大鼠胸脊髓的中间区域释放。参与抑制[3 H]5-HT诱发释放的5-HT受体亚型为5-HT 1B亚型。这些发现可能有助于阐明5-HT在交感神经系统脊髓调节中的复杂作用。© 1994 Wiley利斯公司
Serotonin (5‐HT) nerve terminals innervate sympathetic preganglionic neurons of the intermediolateral cell column (IML); however, neither the depolarization‐induced release of 5‐HT nor the presence of presynaptic modulatory autoreceptors have been directly studied in this system. We used in vitro superfusion of the microdissected intermediate area (including the intermediolateral cell column, intercalated nucleus, and central autonomic nucleus) of the rat thoracic spinal cord to measure basal and stimulated release of preloaded [3H]5‐HT. Elevated K+evoked a concentration‐ and Ca2+dependent release of [3H]5‐HT. Exogenous 5‐HT and the 5‐HT1Bagonist, CGS‐12066B, both decreased the K+‐stimulated release of [3H]5‐HT. A 5‐HT1Bantagonist (methiothepin) blocked the 5‐HT‐ and the CGS‐12066B‐induced inhibition of K+‐evoked release of [3H]5‐HT. A 5‐HT1Aantagonist (NAN‐190) did not alter the inhibitory actions of exogenous 5‐HT. Moreover, a 5‐HT1Aagonist (8‐OH‐DPAT), a 5‐HT2A/2Cagonist [(+/‐)‐DOI hydrochloride], and a 5‐HT3agonist (2‐methyl‐5‐HT) did not alter the K+evoked release of [3H]5‐HT. These data demonstrate that 5‐HT is released from the intermediate area of the rat thoracic spinal cord. The 5‐HT receptor subtype involved in the inhibition of the evoked release of [3H]5‐HT is of the 5‐HT1Bsubtype. These findings may help clarify the complex role of 5‐HT in spinal regulation of the sympathetic nervous system. © 1994 Wiley‐Liss, Inc