Central α-adrenoceptor subtypes involved in the emetic pathway in cats
Central α-adrenoceptor subtypes involved in the emetic pathway in cats
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DOI：
10.1016/0014-2999(92)90562-i
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发表时间：
1992-12
影响因子：
5
通讯作者：
Hikasa Yoshiaki;Akiba Tooru;Iino Yoshihisa;Matsukura Motoharu;Takase Katsuaki;Ogasawara Shigeo
中科院分区：
文献类型：
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作者：
Hikasa Yoshiaki;Akiba Tooru;Iino Yoshihisa;Matsukura Motoharu;Takase Katsuaki;Ogasawara Shigeo
脑室内（i. c. v.）注射可乐定、甲苯噻嗪、肾上腺素和甲氧胺在猫中按效力顺序引起剂量依赖性呕吐。iv具有α2受体阻断活性的育亨宾和酚妥拉明可拮抗可乐定、甲苯噻嗪和肾上腺素引起的呕吐，而iv具有α1受体阻断活性的哌唑嗪则不拮抗。与此相反，甲氧胺引起的呕吐是拮抗哌唑嗪，但不是育亨宾。甲苯噻嗪和肾上腺素诱导的呕吐不能通过i. c. v. 6-羟基多巴胺治疗来预防，但可以通过i. c. v.利血平治疗来预防。消融最后区并对极邻近区域进行一定程度的损伤，可消除每种α-肾上腺素受体激动剂诱导的呕吐。这些结果表明，中枢α_1和α_2肾上腺素能受体均参与猫的呕吐通路，但α_2肾上腺素能受体似乎起主要作用。研究还表明，脑中的单胺，特别是5-羟色胺，参与α-肾上腺素受体介导的呕吐的调节。
The intracerebroventricular (i.c.v.) injection of clonidine, xylazine, adrenaline and methoxamine elicited dose-dependent vomiting in cats in that order of potency. The vomiting induced by clonidine, xylazine and adrenaline was antagonized by i.c.v. yohimbine and phentolamine possessingα2-adrenoceptor-blocking activity, but not by prazosin showingα1-adrenoceptor-blocking activity. In contrast, methoxamine-induced vomiting was antagonized by prazosin, but not by yohimbine. The vomitting induced by xylazine and adrenaline was not prevented by i.c.v. 6-hydroxydopamine treatment, but was prevented by i.c.v. reserpine treatment. Ablation of the area postrema with some damage to extremely adjacent areas abolished the vomiting induced by each α-adrenoceptor agonist. These results indicate that both centralα1- andα2-adrenoceptors are involved in the emetic pathway in cats, althoughα2-adrenoceptors seem to have the main role. It is also suggested that monoamines, and in particular 5-hydroxytryptamine in the brain, are involved in the regulation of α-adrenoceptor-mediated vomiting.