Miwa Y, Koshikawa N, Miyata N, Koshida Y, Kobayashi M, Cools A R
Department of Pharmacology, Nihon University School of Dentistry, Tokyo, Japan.
Eur J Pharmacol. 1995 Apr 13;277(1):63-9. doi: 10.1016/0014-2999(95)00066-t.
Bilateral injections of the thyrotropin-releasing hormone (TRH) analogue, N alpha-[((S)-4-oxo-2-azetidinyl)-carbonyl]-L-histidyl-L-prolinamide dihydrate (YM-14673, 0.1 microgram and 1 microgram/0.2 microliters), into the nucleus accumbens, the dorsal and ventrolateral striatum produced repetitive jaw movements in a dose-dependent manner. The effects were greatest in the nucleus accumbens and smallest in the ventrolateral striatum. Pattern of the movements differed from that produced by injections of a mixture of SKF 38393 (5 micrograms) and quinpirole (10 micrograms); frequent tongue protrusions were evident in rats treated with the mixture but those were not seen in YM-14673-treated rats. TRH (1 microgram, 10 micrograms and 30 micrograms/0.2 microliters) did not evoke jaw movements from any of the sites. The non-selective dopamine receptor antagonist, cis-(Z)-flupentixol (10 micrograms), significantly reduced the response to administration of YM-14673 (1 microgram) into the nucleus accumbens or dorsal striatum, while the 5-hydroxytryptamine (5-HT)2A receptor antagonist, 2-(2-dimethylaminoethylthio)-3-phenylquinoline hydrochloride (ICI 169,369, 0.2 micrograms), did not affect the response to YM-14673 (1 microgram). Given intrathecally (0.5 microgram/5 microliters), both YM-14673 and TRH produced wet-dog shakes. Although the mechanisms giving rise to the display of jaw movements after intrastriatal injections of YM-14673 remain unknown, stimulation of the dopamine D1/D2 receptors may at least partly contribute to these effects. Anyhow, these mechanisms differ from that underlying the ability of YM-14673 and TRH to elicit wet-dog shakes, a mechanism that is known to involve serotonergic processes.
向伏隔核、背侧和腹外侧纹状体双侧注射促甲状腺激素释放激素（TRH）类似物Nα-[((S)-4-氧代-2-氮杂环丁烷基)-羰基]-L-组氨酰-L-脯氨酰胺二水合物（YM-14673，0.1微克和1微克/0.2微升），可剂量依赖性地产生重复性下颌运动。这些作用在伏隔核中最大，在腹外侧纹状体中最小。运动模式与注射SKF 38393（5微克）和喹吡罗（10微克）的混合物所产生的不同；用该混合物处理的大鼠中频繁出现伸舌现象，但在YM-14673处理的大鼠中未观察到。TRH（1微克、10微克和30微克/0.2微升）在任何部位均未引起下颌运动。非选择性多巴胺受体拮抗剂顺式-(Z)-氟哌噻吨（10微克）可显著降低向伏隔核或背侧纹状体注射YM-14673（1微克）后的反应，而5-羟色胺（5-HT）2A受体拮抗剂2-(2-二甲基氨基乙基硫基)-3-苯基喹啉盐酸盐（ICI 169,369，0.2微克）不影响对YM-14673（1微克）的反应。鞘内注射（0.5微克/5微升）时，YM-14673和TRH均可产生湿狗样抖动。虽然纹状体内注射YM-14673后引起下颌运动表现的机制尚不清楚，但多巴胺D1/D2受体的刺激可能至少部分促成了这些作用。无论如何，这些机制与YM-14673和TRH引发湿狗样抖动的潜在机制不同，已知后者涉及血清素能过程。
