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采用脑立体定向和脑内微量注射技术研究了猫延髓嘴侧腹外侧区（ｒＶＬＭ）微量注射内皮素－１（ＥＴ－１），对平均动脉压（ＭＡＰ）、心率（ＨＲ）和肾交感神经活动（ＲＮＡ）的影响。结果表明：ｒＶＬＭ内微量注射ＥＴ－１（２ｐｍｏｌ，０．５μｌ），可显著升高平均动脉压、增加心率和增强肾交感神经活动，并存在量－效间的正相关关系。双侧颈部迷走神经切断后，不影响上述结果。静脉预先给与α－受体阻断剂（Ｒｅｇｉｔｉｎｅ，５ｍｇ／ｋｇ），能显著抑制ＥＴ－１的上述升压作用。放射免疫观察到，ｒＶＬＭ内微量注射ＥＴ－１后，血浆精氨酸升压素（ＡＶＰ）含量显著升高，其变化与血压变化呈显著一致。以上结果提示，（１）ｒＶＬＭ内ＥＴ－１参与心血管活动的中枢调节，并显示有部位特异性；（２）该调节作用主要通过改变交感神经传出活动实现，而与迷走神经活动无关；（３）ｒＶＬＭ内ＥＴ－１还可能激动下丘脑室旁核及视上核的升压素能神经元，从而参与心血管活动的调节。
Microinjection of endothelin-1 (ET-1) into the rostral ventrolateral medulla (rVLM) of the cat was performed using stereotactic and intracerebral microinjection techniques. The mean arterial pressure (MAP), heart rate (HR) and renal sympathetic nerve Effect of activity (RNA). The results showed that microinjection of ET-1 (2 pmol, 0.5μl) into rVLM significantly increased mean arterial pressure, increased heart rate and increased renal sympathetic nerve activity, and there was a positive correlation between quantity and effect. After bilateral cervical vagotomy, does not affect the above results. Intravenous administration of an α-receptor blocker (Regitine, 5 mg / kg) significantly inhibited the above-mentioned step-up effect of ET-1. Radioimmunoassay showed that the plasma arginine vasopressin (AVP) content was significantly increased after microinjection of ET-1 into rVLM, and the change was in good agreement with the change of blood pressure. The above results suggest that: (1) ET-1 is involved in central regulation of cardiovascular activity in rVLM and shows site specificity; (2) this regulation is mainly achieved by altering sympathetic efferent activity but not vagal activity; ( 3) ET-1 in rVLM may also activate vasopressinergic neurons in paraventricular hypothalamic nucleus and supraoptic nucleus to participate in the regulation of cardiovascular activity.