脊髓蛛网膜下腔注射肾上腺素受体拮抗剂及激动剂对延髓腹面升压区引起的肾神经电活动的影响

Effect of Intrathecal Injection of Adrenoreceptor Antagonists and Agonists at Spinal Cord on RSNA Response to Stimulation of VSMp

实验在38只乌拉坦麻醉的大鼠进行,观察下胸段(T_8～T_(10))蛛网膜下腔微量注射α肾上腺素受体拮抗剂或激动剂,对延髓腹面升压区(VSMP)兴奋所诱发的肾交感神经电活动(RSNA)的影响。结果表明:(1)下胸段蛛网膜下腔微量注射α_1;受体拮抗剂哌唑嗪衰减了L—谷氨酸作用于VSMp诱发的RSNA增强效应;(2)哌唑嗪的衰减作用表现明显的量效依赖性;(3)α_1受体激动剂苯肾上腺素在提高RSNA基础电活动的同时,加强了VSMp兴奋所诱发的RSNA增强效应,提示下胸段SPN的α_1肾上腺素受体参与介导延髓腹面升压区调控肾交感神经电活动过程。

Experiments were performed on 38 urethane anesthetized wistar rats to assess the effect of in- trathecal injection of α-adrenoreceptor antagonists and agonists (at inferior thoracic level)on renal sym- pathetic nerve activities (RSNA) from the excitation of pressor area of ventral surface medulla (VSMp). The results showed: (1) Increases in RSNA induced by application of L-glutamate to the VSMp could be reversibly blocked by intrathecal injection of α_1-adrenoreceptor antagonist prazosin. (2) The blockage effects of prazosin had a dose dependent relationship. (3)The basal value and increase in RSNA due to VSMp stimulation were enhanced by intrathecal α_1-adrenoreceptor aganist phenylephrine. These results indicate that α_1-adrenoreceptors at inferior thoracic level are involved in the process of VSMp integrated RSNA.