过刊浏览

延髓腹外侧头端区在第四脑室注射P物质所致升压中的作用

张小慧, 倪慧

南京医科大学生理学教研室. 南京 210029

摘要

实验用乌拉坦麻醉、肌肉麻痹、人工呼吸的家兔。将P物质(SP,0.8ng／kg，溶于100μl人工脑脊液中)注入第四脑室(ivt)引起肺动脉压(PAP)升高或降低，但以升压反应为主。与此同时，颈动脉压(CAP)上升，心率(HR)减慢；而在第四脑室内注入同容积的人工脑脊液对PAP，CAP和HR无明显影响。若在ivtSP之前，预先向双侧延髓腹外侧头端区(rVLM)微量注射SP受体拮抗剂[D－Pro~(2)，D－Phe~(7)，D-Trp~(9)]－SP（5～10ng溶于0.5μl人工脑脊液中）或酚妥拉明(2～3μg溶于0.5μl人工脑脊液中)，可阻断SP引起的肺动脉和颈动脉升压反应。而在双侧延髓腹外侧尾端区(cVLM)内注射同样剂量的SP受体拮抗剂或酚妥拉明则不能阻断上述两种升压反应。以上结果表明，SP引起的肺动脉和颈动脉升压反应是由rVLM中的SP受体和α-肾上腺素能受体介导的。

关键词： P物质; 肺动脉压; 颈动脉压; 升压反应; 延髓腹外侧头端区; α-肾上腺素能受体

Role of rostral ventrolateral medulla in the pressor response to intraventricular (4th) injection of substance P

Zhang Xiaohui, Ni Hui

Department of Physiology，Nanjing Medical University. Nanjing 210029,China

Abstract

Experiments were done in rabbits anaesthetized with urethane and immobilized under artificial respiration. It was found that substance P (SP, 0.8ng/kg dissolved in 100 #mu#l artificial cerebro-spinal fluid, CSF) injected into the 4th ventricle induced either a rise or a drop of pulmonary arterial pressure (PAP) with predominated pressor response. In addition, a rise in carotid arterial pressure (CAP) and reduction in heart rate (HR) were also observed, whereas no significant alteration in PAP, CAP and HR was observed. Microinjection of SP receptor antagonist [D-Pro~(2), D-Phe~(7), D-Trp~(9)] -SP (5-10 ng dissolved in 0.5 #mu#l CSF) or phentolamine (2-3 #mu#g dissolved in 0.5#mu#l CSF) into the bilateral rostral ventrolateral medulla (rVLM) prior to intraventricular injection of SP could block the SP-induced pressor responses in pulmonary and carotid arteries, while microinjection of SP receptor antagonist or phentolamine into bilateral caudal ventrolateral medulla (cVLM) at the same dosage had no effect.

Key words: Substance P;Pulmonary arterial pressure;Carotid arterial presrure;Pressor response rostral ventrolateral medulla;#alpha#-adrenergic receptor;

收稿日期：　　录用日期：

通讯作者：　　E-mail:

引用本文：

张小慧, 倪慧. 延髓腹外侧头端区在第四脑室注射P物质所致升压中的作用[J]. 生理学报 1998; 50 (2): .

Zhang Xiaohui, Ni Hui. Role of rostral ventrolateral medulla in the pressor response to intraventricular (4th) injection of substance P. Acta Physiol Sin 1998; 50 (2): (in Chinese with English abstract).