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目的：研究内皮素１（ＥＴ１）在大鼠孤束核对心血管活动的作用及其机制。方法：麻醉大鼠单侧孤束核微注射ＥＴ１后，观察血压、心率、左室收缩压和ｄｐ／ｄｔｍａｘ以及动脉压力反射敏感性的变化。并观察预先孤束核微注射ＥＴ受体拮抗剂或预先静脉注射神经节阻断剂对ＥＴ１在大鼠孤束核中作用之影响。结果：在乌拉坦麻醉大鼠，单侧孤束核微注射３种剂量（１．０，３．３和１０．０ｐｍｏｌ）的ＥＴ１均可引起血压、左室收缩压和ｄｐ／ｄｔｍａｘ升高，呈剂量依赖性；心率轻度减慢，与剂量不相关；血压持续升高９０ｍｉｎ以上。孤束核微注射选择性ＥＴＡ受体拮抗剂ＰＤ１４７９５３或非选择性ＥＴ受体拮抗剂ＰＤ１４２８９３均不影响血压和心率。预先静脉注射六烃季铵或预先孤束核微注射ＰＤ１４７９５３均可取消外源性ＥＴ１在孤束核的心血管作用。在α氯醛糖麻醉大鼠，孤束核微注射ＥＴ１（３．３ｐｍｏｌ）可显著抑制动脉压力感受性反射。结论：内皮素１通过孤束核ＥＴＡ受体参与心血管活动的中枢调控，但不起张力性作用；该调节作用依赖自主神经系统。
Objective: To investigate the effect of endothelin1 (ET1) on cardiovascular activity in rat solitary tract and its mechanism. Methods: Anesthetized rats unilateral nucleus tractus microinjection of ET 1, observed changes in blood pressure, heart rate, left ventricular systolic and dp / dtmax and arterial pressure reflex sensitivity. And observe the pre-solitary beam microinjection of ET receptor antagonist or pre-intravenous injection of ganglion blockers on ET 1 in rat solitary nucleus. Results: In the urazan anesthetized rats, unilateral microvascular injection of solitary tract at three doses (1.0,3.3 and 10.0pmol) of ET 1 can cause blood pressure, left ventricular systolic pressure and dp / dtmax High, in a dose-dependent; mild heart rate slowed, and the dose is not related; blood pressure continued to rise above 90min. Neonatal micro-injection of selective ETA receptor antagonist PD147953 or non-selective ET receptor antagonist PD142893 did not affect blood pressure and heart rate. Pre-injection of six hydrocarbon quaternary ammonium or pre-solitary tract microinjection of PD147953 can be abolished exogenous ET 1 in the nucleus of solitary tract of cardiovascular. In α-chloralose anesthetized rats, solitary tract microinjection of ET 1 (3.3pmol) significantly inhibited arterial baroreflex. Conclusion: Endothelin 1 participates in the central regulation of cardiovascular activity through the solitary tract nucleus ETA receptor, but it can not afford the tonic effect; this regulation depends on the autonomic nervous system.