Gao Li, Zhang Wen-Hui, Wang Yu-Wei, Zhu Xiao-Jia, Xiao Yu-Jie, Gao Qian-Wen, Li Wei, Chen Long
School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023.
Taizhou Fourth People's Hospital, Taizhou 225300.
Zhongguo Ying Yong Sheng Li Xue Za Zhi. 2020 Sep;36(5):408-413. doi: 10.12047/j.cjap.5992.2020.087.
To explore the positive inotropic effect of atractylodin which is major active component of Rhzoma Atractylodis Lanceae and its underlying mechanism. For study, six male SD rats were randomly selected for the heart pressure-volume loop (P-V loop) experiment. The effects of atractylodin (3 mg/kg, intraperitoneal injection) on hemodynamic parameters such as LVDP (left ventricular developed pressure), SW (stroke work), HR (heart rate), CO (cardiac output), SBP (systolic blood pressure) and DBP (diastolic blood pressure) were analyzed. For study, left ventricular developed pressure (LVDP) from the Langendroff-perfused isolated rat heart was analyzed before as the control and after atractylodin perfusion. For study, the effects of atractylodin and atractylodin with H89 (PKA inhibitor) or KN-93 (CaMKII inhibitor or Calyculin A (PP1, PP2A inhibitor) on LVDP were analyzed. The experiments were separated into four parts with six isolated hearts for each as follows: (1) Control→0.1→1→10 μmol/L atractylodin; (2) Control→200 nmol/L H89 (PKA inhibitor)→200 nmol/L H89+10 μmol/L atractylodin; (3) Control→500 nmol/L KN-93 (CaMKII inhibitor)→500 nmol/L KN-93+10 μmol/L atractylodin; (4) Control→10 nmol/L Calyculin A (PP1, PP2A inhibitor)→10 nmol/L Calyculin A+10 μmol/L atractylodin. For the study of rat left ventricular myocyte Ca transient induced by field stimulation, the experiment design was the same as study. The six cells from the different rats were used for each part experiment. ① Atractylodin (3 mg/kg) significantly increased the heart rate, cardiac output and stroke work (＜0.05) and decreased the diastolic blood pressure (＜0.05). ② Atractylodin (0.1, 1, 10 μmol/L) significantly increased the LVDP in a concentration dependent manner (＜0.05). The positive inotropic effect of atractylodin could be blocked by PKA inhibitor H89. ③ Atractylodin (10 μmol/L) significantly increased the amplitude of SR Ca transient amplitude mediated by facilitating sarcoplasmic reticulum SERCA2a. The enhanced amplitude of SR Ca transient could be blocked by PKA inhibitor H89. Atractylodin had positive inotropic effect in rat heart both and with decreased diastolic blood pressure and its underlying mechanism was mediated by PKA. Based on the fact that the atractylodin exerted its positive inotropic effect was mediated by PKA, the PKA-SERCA2a signaling pathway might be the mechanism of the atractylodin's positive inotropy.
探讨茅苍术主要活性成分苍术素的正性肌力作用及其潜在机制。选取6只雄性SD大鼠，随机分为6组，进行心脏压力 - 容积环（P - V环）实验。分析苍术素（3 mg/kg，腹腔注射）对左心室舒张末压（LVDP）、每搏功（SW）、心率（HR）、心输出量（CO）、收缩压（SBP）和舒张压（DBP）等血流动力学参数的影响。在Langendorff灌注的离体大鼠心脏实验中，分析灌注苍术素前后的左心室舒张末压（LVDP）。分析苍术素以及苍术素与H89（PKA抑制剂）或KN - 93（CaMKII抑制剂）或Calyculin A（PP1、PP2A抑制剂）对LVDP的影响。实验分为四个部分，每组6个离体心脏，具体如下：（1）对照组→0.1→1→10 μmol/L苍术素；（2）对照组→200 nmol/L H89（PKA抑制剂）→200 nmol/L H89 + 10 μmol/L苍术素；（3）对照组→500 nmol/L KN - 93（CaMKII抑制剂）→500 nmol/L KN - 93 + 10 μmol/L苍术素；（4）对照组→10 nmol/L Calyculin A（PP1、PP2A抑制剂）→10 nmol/L Calyculin A + 10 μmol/L苍术素。在大鼠左心室肌细胞场刺激诱导的Ca2+瞬变实验中，实验设计与上述实验相同。每个部分实验使用来自不同大鼠的6个细胞。①苍术素（3 mg/kg）显著增加心率、心输出量和每搏功（P＜0.05），降低舒张压（P＜0.05）。②苍术素（0.1、1、10 μmol/L）以浓度依赖性方式显著增加LVDP（P＜0.05）。苍术素的正性肌力作用可被PKA抑制剂H89阻断。③苍术素（10 μmol/L）通过促进肌浆网SERCA2a显著增加SR Ca2+瞬变幅度。SR Ca2+瞬变幅度的增强可被PKA抑制剂H89阻断。苍术素在大鼠心脏中具有正性肌力作用，同时伴有舒张压降低，其潜在机制由PKA介导。基于苍术素发挥正性肌力作用由PKA介导这一事实，PKA - SERCA2a信号通路可能是苍术素正性肌力作用的机制。
