Basics: Pathophysiology


In all forms of PA, aldosterone production is excessive to the body's requirements and relatively autonomous with regard to its normal chronic regulator, the renin-angiotensin II system. This results in excessive sodium re-absorption through amiloride-sensitive epithelial sodium channels within the distal nephron, leading to HTN and suppression of renin-angiotensin II. Urinary loss of potassium and hydrogen ions, exchanged for sodium at the distal nephron, may result in hypokalaemia and metabolic alkalosis if severe and prolonged enough. The exact causes of excessive, autonomous aldosterone production in aldosterone-producing adenoma and bilateral adrenal hyperplasia are unknown, but genetic factors related to adrenal cortical  ellular growth regulation and/or steroid biosynthesis are likely to be involved.


In FH-I, the causative hybrid gene encodes a hybrid enzyme of unique structure that synthesises aldosterone but, unlike CYP11B2, is regulated by adrenocorticotrophic hormone (ACTH) and not by angiotensin II. Aldosterone production in FH-I is therefore regulated by ACTH rather than by angiotensin II, and can be suppressed and managed by administering small doses of glucocorticoids such as dexamethasone.


Mutations in KCNJ5 (which encodes an inwardly-rectifying potassium channel) lead to reduced potassium/sodium channel selectivity and sodium influx, predisposing to cell membrane depolarisation, increased calcium influx, increased expression of genes promoting aldosterone synthesis, and increased aldosterone production by adrenocortical cells. How these effects lead to adrenal cell proliferation and tumour development remains uncertain.



Although morbidity in PA mainly results from HTN, experimental and clinical evidence strongly suggests that aldosterone excess can bring about adverse cardiovascular sequelae (including remodelling and fibrosis) independently of its hypertensive effects. In animal studies, both aldosterone excess and a high salt intake appear to be necessary for induction of cardiac fibrosis, and coronary vasculitis has been observed to be an early manifestation. These effects were preventable by the administration of mineralocorticoid receptor antagonists. The doses of aldosterone used in experimental studies have been very large, and the results of these studies may, therefore, have limited applicability to clinical situations. Nevertheless, several groups have convincingly demonstrated abnormalities in cardiovascular morphology or function in patients with PA that appear to be out of proportion to the

elevation in BP. These have included:


·        Increased left ventricular mass index and reduced diastolic function, both of which markedly improved following specific treatment of PA

·        Reduced myocardial perfusion at rest and during exercise

·        左心室质量指数增加和舒张功能降低,经过特异性假性醛固酮增多症治疗后两项指标均明显好转

·        静止或运动时的心肌灌注减少 


·        Increased myocardial backscatter (an echo marker of myocardial fibrosis)

·        Increased proteinuria (as evidence of renal glomerular damage)

·        心肌背向散射(心肌纤维化的回声标记)增加

·        蛋白尿增加(肾小球损害的标志)

·        A greater incidence of cardiovascular events, which was reversed following specific surgical or medical treatment.

·        Evidence of left ventricular remodelling was also reported in individuals with genetically proven FH-I who had biochemical evidence of aldosterone excess but had not yet developed HTN.


·        心血管事件的发生率较高,经相关手术或药物治疗后可逆转

·        研究结果证明遗传学证实为家族性醛固酮增多症I型且生化检查显示有醛固酮过多但还没有发展成为原发性高血压的个体有左室重构现象


List of sample translations 

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Sample 3_Medical Devices_Atherectomy system 

Sample 4_Medical:healthcare_patient report

Sample 5_Phamarceutical_drug mechanism of action

Sample 6_Psychology_test