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目的 研究大鼠侧脑室注射（ｉｃｖ）［Ｄ－Ｔｒｐ１１］－神经降压素（［Ｄ－Ｔｒｐ１１ ］－ＮＴ）对心血管活动的影响。方法 将［Ｄ－Ｔｒｐ１１ ］－ＮＴ注入乌拉坦麻醉的雄性ＳＤ大鼠（４０只）侧脑室，观察血压（ＢＰ）和心率（ＨＲ）的变化。结果 ｉｃｖ ［Ｄ－Ｔｒｐ１１］－ＮＴ（１０ μｇ）可引起血压下降和心率减慢；切断大鼠的两侧颈部迷走神经后，再ｉｃｖ［Ｄ－Ｔｒｐ１１］－ＮＴ，所有动物的降压和降心率反应均明显减弱。预先ｉｃｖ［Ｄ－Ｔｒｐ１１］－ＮＴ（２．５ μｇ），可阻断神经降压素（ＮＴ）的中枢降压和降心率反应。结论 ［Ｄ－Ｔｒｐ１１ ］－ＮＴ在一定的剂量范围内具有激动剂的特性；ＮＴ的中枢心血管抑制效应是由脑中的ＮＴ受体介导的。
Objective To investigate the effects of intracerebroventricular (icv) [D-Trp11] -stimotulin ([D-Trp11] -NT) on cardiovascular activity in rats. Methods [D-Trp11] -NT was injected into the lateral cerebral ventricle of 40 male SD rats anesthetized with urethane to observe the changes of blood pressure (BP) and heart rate (HR). Results icv [D-Trp11] -NT (10 μg) caused a decrease in blood pressure and heart rate. After both sides of the cervical vagal nerve were severed, icv [D-Trp11] -NT, Heart rate response were significantly reduced. Pre-icv [D-Trp11] -NT (2.5 μg) blocked the central hypotensive and antihypertensive responses to neurotensin (NT). Conclusions [D-Trp11] -NT has agonist properties over a range of doses; the central cardiovascular inhibitory effect of NT is mediated by NT receptors in the brain.