延髓腹外侧区对L－谷氨酸钠在蓝斑复合核所致呼吸效应的影响

Influence of Ventrolateral Medulla on Respiratory Excitation Caused by Microinjection of L-glutamate into Locus Coeruleus Complex Area

７１只家兔，乌拉坦静脉麻醉，在自主呼吸下进行实验。结果如下：①蓝斑复合核（Ｌｃ－Ｓｃ）区微量注射谷氨酸钠（Ｇｌｕ），可致呼吸频率加快、每ｍｉｎ通气量明显增加，其增加值分别为（２３．０±４．０）％和（２５．０±３．０）％，与给药前及生理盐水对照组比较，差异均有极显著性意义（均为Ｐ＜０．０１）。平均动脉压和心率无明显变化。②延髓头端腹外区（ＲＶＬＭ）分别预注射哌唑嗪和阿托品，可阻断Ｇｌｕ在Ｌｃ－Ｓｃ区的呼吸兴奋效应，而在ＲＶＬＭ预注射育亨宾或心得安，对刺激Ｌｃ－Ｓｃ所致呼吸兴奋效应无明显影响。结果提示：Ｌｃ－Ｓｃ神经元参与呼吸的调节，此效应主要通过ＲＶＬＭ的α受体和Ｍ受体介导。

Experiments were performed on 71 rabbits anesthetized with urithane under auto-ventilation. The results showed:①Microinjection of L-glutemate into locus coeruleus complex area led to a marked increase in respiratory frequency and minute ventilation volume,The increase rate was(23.0±4.0)%and(25.0±3.0)% respectively compared with pre-injection. The alteration was significant(P<0.01)as compared with injection of 0.9%natrii chloride. The mean arterial pressure and cardiac rate had no change. ②The effect of L-glutamate on respiration was blocked by pre-injection of prazosin or atropine into rostral ventrolateral medulla,but not blocked by pre-injection of yohimbin or propranolol.These results suggest that neurons in locus coeruleus complex may be involved in the regulation of respiratory movement,and the effect is mainly mediated by α1 and M-receptors in ventrolateral medulla rostrum.