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腺苷A1受体在离体延髓脑片上对节律性呼吸的调制

王剑莉, 吴中海, 王宁黔

南方医科大学生理学教研室.广东，广州 510515

摘要

实验旨在探讨腺苷A1受体在对基本呼吸节律调制中的可能作用。制作新生大鼠离体延髓脑片标本，主要包含面神经后核内侧区（the medial region of the nucleus retrofacialis，mNRF），并保留舌下神经根的完整。以改良Kreb’s液灌流脑片,记录mNRF吸气神经元的电活动，并同步记录舌下神经根呼吸节律性放电（respiratory rhythmical discharge activity,RRDA）。在灌流液中先分别单独给予腺苷A1受体的特异性拮抗剂 8-环戊-1,3-二丙基黄嘌呤（8-cyclopentyl- 1,3-dipropylxanthine,DPCPX）和特异性激动剂 R-苯异丙基-腺苷（R-phenylisopropyl-adenosine，R-PIA）;再分别先后给予R-PIA和R-PIA+ DPCPX，观察RRDA和吸气神经元电活动的变化。结果显示，给予腺苷A1受体拮抗剂DPCPX后，呼气时程和呼吸周期明显缩短，吸气神经元中期放电的频率和峰频率显著增大；给予腺苷A1受体激动剂R-PIA后，吸气时程，积分幅度和吸气神经元中期放电的频率和峰频率均显著性降低，呼吸周期明显延长，且R-PIA的呼吸抑制作用可部分地被DPCPX逆转。实验结果提示，腺苷A1受体可能通过介导吸气神经元的抑制性突触输入参与了节律性呼吸的调制。

关键词： 腺苷A1受体; 面神经后核内侧区; 呼吸节律; 吸气神经元; 放电频率

Adenosine A1 receptors are involved in the modulation of the rhythmical respiration in neonatal rat brainstem slice in vitro

Wang Jianli, Wu Zhonghai, Wang Ningqian

Department of Physiology, the Southern Medical University.Guangzhou 510515.Guangdong

Abstract

This study was designed to investigate whether adenosine A1 receptors could modulate primary rhythmical respiration in mammals. Experiments were performed in in vitro brainstem slice preparations from neonatal rats. These preparations included the medial region of the nucleus retrofacialis (mNRF) with the hypoglossal nerve rootlets retained. The activity of the inspiration-related neurons (I neurons) in mNRF and respiratory rhythmical discharge activity (RRDA) of the hypoglossal nerve rootlets were simultaneously recorded by using microelectrodes and suction electrodes, respectively. Possible roles of adenosine A1 receptors in rhythmical respiration were investigated by administration of adenosine A1 receptor agonist R-phenylisopropyl-adenosine (R-PIA) and its specific antagonist 8-cyclopentyl-1,3- dipropylxanthine (DPCPX) into a modified Kreb’s perfusion solution (MKS). DPCPX induced a significant decrease in the expiratory time and the respiratory cycles, and an increase in the discharge frequency and peak frequency of I neurons in the middle phase of inspiration. However, R-PIA significantly decreased the inspiratory time and integral amplitude as well as prolonged respiratory cycle. Moreover, the discharge frequency and the peak frequency of I neurons were decreased in the middle phase of inspiration, but not in the initial and terminal phases. The effect of R-PIA on rhythmical discharges could be partially reversed by additional application of DPCPX. These results indicate that adenosine A1-receptors are possibly involved in the modulation of rhythmical respiration through the inhibitory synaptic input from I neurons.

Key words: Adenosine A1 receptors;The medial region of the nucleus retrofacialis;Rhythmical respiration;Inspiration-related neurons;Discharge frequency

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引用本文：

王剑莉, 吴中海, 王宁黔. 腺苷A1受体在离体延髓脑片上对节律性呼吸的调制[J]. 生理学报 2005; 57 (1): .

Wang Jianli, Wu Zhonghai, Wang Ningqian. Adenosine A1 receptors are involved in the modulation of the rhythmical respiration in neonatal rat brainstem slice in vitro. Acta Physiol Sin 2005; 57 (1): (in Chinese with English abstract).