Ma J, Peng A, Lin S
Division of Nephrology, Huashan Hospital, Shanghai Medical University, China.
Chin Med J (Engl). 1998 Jan;111(1):17-23.
To investigate the therapeutic effect of Astragali on sodium and water retention in aortocaval fistula-caused experimental congestive heart failure and its involved mechanisms.
In aortocaval fistula-caused chronic (5 wk), heart failure rats treated with and without Astragali 1.0 g/day intraperitoneally, changes of cardiac and renal function, renal response to atrial natriuretic peptide (ANP) were examined. Dot blot analysis was used to determine the effect of Astragali on hypothalamic arginine vasopresin (AVP) mRNA expression, and mRNA expressions of aortic and renal AVP V1a receptor, renal AVP V2 receptor and aquaporin-2 (AQP2) were simultaneously detected by RT-PCR method.
Rats with aortocaval fistula impaired cardiac and renal functions evidenced by higher right atrial pressure (RAP), left ventricular end-diastolic pressure (LVEDP), lower + dP/dtmax of left ventricle, glomerular filtration rate (GFR), renal plasma flow (RPF), urine volume (UV), urinary sodium excretion (UNaV) and free water clearance (CH2O) compared with sham-operated control (P < 0.05). There was no change in serum sodium, hematocrit and plasma osmolality. Astragali could remarkably improve the cardiac and renal functions. Dot blot analysis demonstrated upregulated hypothalamic AVP mRNA expression in this experimental heart failure. The AVP V1a receptor mRNA level of aortic arch and renal medulla were reduced, while in renal cortex it was elevated. The mRNA expressions of AVP V2 receptor and AQP2 were increased in renal cortex while decreased in medulla. Astragali could partially or completely correct those abnormal mRNA expressions. Analysis on plasma atrial natriuretic peptide (ANP), urinary cyclic guanidino monophosphate excretion (UcGMP V), urinary cyclic guanidino monophosphate excretion/plasma atrial natriuretic peptide (UcGMP V/pANP), and further correlation and linear regression analysis between UcGMP V and plasma ANP showed that there was blunted renal response to ANP in heart failure rat, and astragali could improve the renal reaction to ANP significantly.
Chinese herb, astragali have therapeutic effects on sodium and water retention in aortocaval fistula-induced heart failure, the mechanisms of which might be the improvement of cardiac and renal functions, partly correction of abnormal mRNA expressions of AVP system and AQP2, and amelioration of blunted renal response to ANP.
探讨黄芪对主动脉腔静脉瘘所致实验性充血性心力衰竭钠水潴留的治疗作用及其相关机制。
将主动脉腔静脉瘘所致慢性（5周）心力衰竭大鼠分为两组，一组腹腔注射黄芪1.0g/天，另一组不做处理，检测心肾功能变化、肾脏对心房钠尿肽（ANP）的反应。采用斑点杂交分析检测黄芪对下丘脑精氨酸加压素（AVP）mRNA表达的影响，同时用逆转录-聚合酶链反应（RT-PCR）法检测主动脉和肾脏AVP V1a受体、肾脏AVP V2受体及水通道蛋白2（AQP2）的mRNA表达。
主动脉腔静脉瘘大鼠心肾功能受损，表现为右心房压（RAP）、左心室舒张末压（LVEDP）升高，左心室+ dP/dtmax、肾小球滤过率（GFR）、肾血浆流量（RPF）、尿量（UV）、尿钠排泄量（UNaV）及自由水清除率（CH2O）降低，与假手术对照组相比差异有统计学意义（P < 0.05）。血清钠、血细胞比容及血浆渗透压无变化。黄芪可显著改善心肾功能。斑点杂交分析显示，本实验性心力衰竭大鼠下丘脑AVP mRNA表达上调。主动脉弓和肾髓质AVP V1a受体mRNA水平降低，而肾皮质升高。肾皮质AVP V2受体和AQP2的mRNA表达增加，而髓质降低。黄芪可部分或完全纠正这些异常的mRNA表达。对血浆心房钠尿肽（ANP）、尿环磷酸鸟苷排泄量（UcGMP V）、尿环磷酸鸟苷排泄量/血浆心房钠尿肽（UcGMP V/pANP）进行分析，并进一步对UcGMP V与血浆ANP进行相关性和线性回归分析，结果显示心力衰竭大鼠肾脏对ANP的反应减弱，黄芪可显著改善肾脏对ANP的反应。
中药黄芪对主动脉腔静脉瘘所致心力衰竭的钠水潴留具有治疗作用，其机制可能是改善心肾功能、部分纠正AVP系统和AQP2异常的mRNA表达以及改善肾脏对ANP反应减弱的情况。
