南方医科大学学报 ›› 2018, Vol. 38 ›› Issue (10): 1159-.doi: 10.12122/j.issn.1673-4254.2018.10.02

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杏仁中央核对醛固酮在大鼠孤束核水平钠盐摄入非基因组作用的调控

乔虎,王楠,闫剑群   

  • 出版日期:2018-10-20 发布日期:2018-10-20

Role of the central nucleus of the amygdala in regulating the nongenomic effect of aldosterone on sodium intake in rat nucleus tractus solitarius

  • Online:2018-10-20 Published:2018-10-20

摘要: 目的探讨杏仁中央核(CeA)能否影响孤束核水平醛固酮调控钠盐摄入的非基因组作用及初步机制。方法将成年雄性 SD大鼠分为4组,分别行双侧电解损毁CeA(400 μA,25 s)(n=28)、双侧CeA假损毁(n=28)、单侧电解损毁CeA(n=28)及单侧 CeA假损毁(n=26),恢复3 d后,实验动物均行孤束核注射套管置入手术,继续恢复7 d,然后每组又分为醛固酮组和对照组两亚 组,分别注射醛固酮(50 ng/μL)或对照溶液后,记录实验动物30 min内0.3 mol/L NaCl溶液的累计摄入量(mL)。结果30 min 内电解损毁大鼠双侧CeA可消除双侧孤束核注入醛固酮所诱发的0.3 mol/L NaCl摄入增加量(损毁组:0.3±0.04 mL相对于假 损毁组:1.3±0.3 mL)。电解损毁大鼠单侧CeA可减少双侧孤束核注入醛固酮所诱发的0.3 mol/L NaCl摄入增加量,与对照组相 比,在前15 min内单侧损毁组摄钠量仍有显著差异(醛固酮:0.48±0.02 mL,相对于对照组:0.23±0.01 mL;P<0.05),而后15 min 内摄钠量则无明显差异(P>0.05)。30 min内假损毁大鼠双侧孤束核注入醛固酮(50 ng/μL)后,0.3 mol/L NaCl摄入量仍明显增 加(醛固酮:1.3±0.3 mL,相对于对照组:0.25±0.02 mL)[F(3, 224)=24.0;P<0.05]。结论醛固酮在延髓水平调控钠盐摄入的机制 接受双侧CeA下行易化调制,且完整的CeA对于醛固酮在延髓水平正常发挥调控钠盐摄入的非基因组作用是必须的。

Abstract: Objective To reveal the nongenomic effect of aldosterone on the regulation of sodium intake in the nucleus tractus solitarius (NTS) and the role of central nucleus of the amygdala (CeA) in regulating this effect. Methods Adult male SD rats were divided into four groups and underwent operations to induce bilateral CeA electrolytic lesions (400 μA, 25 s; n=28), bilateral sham CeA lesions (n=28), unilateral CeA lesions (n=28), or unilateral sham CeA lesions (n=26). After 3 days of recovery, the rats received implantation of a stainless steel 23-gauge cannula wih two tubes into the NTS followed by a recovery period of 7 days. The rats in each group were then divided into two subgroups for microinjection of aldosterone (50 ng/μL) or control solution in the NTS, and the cumulative intake within 30 min of 0.3 mol/L NaCl solution was recorded for each rat. Results Bilateral CeA lesions (3 days) eliminated the increased 0.3 mol/L NaCl intake induced by aldosterone microinjected into the NTS (0.3±0.04 mL in CeA lesion group vs 1.3±0.3 mL in sham lesion group). Unilateral CeA lesion (3 days) reduced aldosteroneinduced increase of NaCl intake in the first 15 min (P<0.05) but not in 15-30 min (P>0.05). In rats with sham lesions, aldosterone (50 ng/μL) still induced a significant increase in NaCl intake [1.3±0.3 mL vs 0.25±0.02 mL in the control group; F (3, 224)=24.0, P< 0.05]. Conclusion The regulation of sodium intake by aldosterone is subjected to descending facilitatory modulation by the bilateral CeA, and CeA integrity is essential for aldosterone to execute the nongenomic effect in regulating rapid sodium intake.