猫头端延髓腹外侧区微量注射内皮素-1对心脏节律的影响

THE EFFECT OF MICROINJECTION OF ENDOTHELIN 1 INTO ROSTRAL VENTROLATERAL MEDULLA ON HEART RHYTHM IN CATS

目的和方法：本工作采用脑立体定位和微量注射的方法，研究猫头端延髓腹外侧区（ｒＶＬＭ）微量注射内皮素１（ＥＴ１）对心脏节律的影响。结果：在正常心脏，ｒＶＬＭ内微量注射ＥＴ１（２ｐｍｏｌ）不引起心脏节律的紊乱；在缺血心脏，ｒＶＬＭ内微量注射ＥＴ１则引起严重的心脏节律的紊乱，美托洛尔（ｍｅｔｏｐｒｏｌｏｌ，１．５ｍｇ／ｋｇ，β１肾上腺素能受体阻滞剂）对其不能完全有效地抑制。结论：中枢内ＥＴ１可能在心肌缺血时，对心律紊乱的发生。

Abstract Aim and Methods:To study the effects of the rostral ventrolateral medulla (rVLM) microinjection of ET 1 on cardiac rhythm by using sterotaxic technique and microinjection method. Results: (1)Microinjection of 2 pmol ET 1 into rVLM could not induce ventricular arrhythmias(VA) in normal heart. (2)During acute myocardial ischaemia, it induced a severe ventricular arrhythmia (VA), and metoprolol (1. 5 mg/kg, a betal blocker)could not inhibit it effectively. Conclusion:The central ET 1 plays an important role in inducing or aggravating heart rhythm disorder in acute myocardiac ischaemia. endothelin 1; rostralventrolateral medulla; heart rhythm disorder; cats