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神经肽Y可减轻大鼠血管α_(1)肾上腺素受体亚型的脱敏作用

董尔丹, 陈明哲, 韩启德

北京医科大学第三医院. 北京(100083)

摘要

以离体大鼠主动脉与肾动脉对去甲肾上腺素(NE)的收缩反应分别代表α_(1B)与α_(1A)亚型肾上腺素受体(AR)激动时的生物学效应。血管 经NE10μmol/L温育2h后, α_(1 )-AR介导心缩效应的敏感性显著降低, 其中α_(1B)亚型AR的脱敏程度显著大于α_(1A)亚型AR。上述经NE温育的血管, 在神经肽Y(NPY)0.5μmol/L存在时, α_(1B)亚 型AR的脱敏程度显著减轻。NE收缩主动脉的两时相分析表明, 脱敏时主要表现为相性收缩时间延长, 收缩幅度降低, 而紧张性收缩并无显著改变; 在NPY存在时上述相性收缩改变消失 。提示α_(1B)亚型AR脱敏的机制主要与细胞内Ca~(2+)动员减慢减少有关。表3 参10

关键词： α_(1)－肾上腺素受体; 脱敏; 神经肽Y; 受体亚型; 血管

Neuropeptide Y reduces desensitization of #alpha#_(1)adrenoceptors in rat blood vessels

Dong Erdan, Chen Mingzhe, Han Qide

The Third Hospital, Beijing Medical University. Beijing

Abstract

Vasoconstrictive responses to norepinephrine(NE) in isolated rat aorta and renal artery were respectively taken to represent the biological responses mediated by #alpha#_(1B) and #alpha#_(1A) subtype adrenoceptor(AR). After blood vessels were incubated with 10 #mu#mol/L NE for 2h, #alpha#_(1)-AR mediated vasocontraction was desensitized significantly, #alpha#_(1B)-AR being more marked than #alpha#_(1A)-AR. In the presence of 0.5 #mu#mol/L neuropeptide Y (NPY), desensitization of #alpha#_(1B)-AR was attenuated significantly. In rat aorta the NE-mediated contraction comprised both phasic and tonic elements. After the incubation with NE, the phasic contraction period was prolonged but magnitude decreased, while no change was found for the tonic contraction. In the presence of NPY, the changes of phasic contraction caused by NE preincubation disappeared. It is suggested that retardation and reduction of intracellular Ca~(2+) release were involved in the mechanism for desensitization of #alpha#_(1B)-AR.

Key words: #alpha#_(1)-adrenoceptor;Desensitization;Neuropeptide Y;Receptor subtypes; Blood vessel

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引用本文：

董尔丹, 陈明哲, 韩启德. 神经肽Y可减轻大鼠血管α_(1)肾上腺素受体亚型的脱敏作用[J]. 生理学报 1994; 46 (4): .

Dong Erdan, Chen Mingzhe, Han Qide. Neuropeptide Y reduces desensitization of #alpha#_(1)adrenoceptors in rat blood vessels. Acta Physiol Sin 1994; 46 (4): (in Chinese with English abstract).