Feraille Éric, Olivier Valérie
Département de physiologie cellulaire et métabolisme, Université de Genève, Centre médical universitaire, 1 rue Michel-Servet, CH-1211 Genève 4, Suisse.
Med Sci (Paris). 2021 Apr;37(4):359-365. doi: 10.1051/medsci/2021032. Epub 2021 Apr 28.
The kidney plays a major role to maintain the constancy of the "milieu intérieur" by adjusting the urinary excretion of water and solutes to the requirement of the body balance. This function is coordinated with elimination of waste products generated among others by the catabolism of proteins and nucleic acids. To cope with these two major functions, the human kidneys generate each day about 180 L of ultrafiltrate from plasma and reabsorbs the vast majority of filtered water and solutes to excrete daily about one-two liter(s) of urine containing concentrations of sodium, potassium and chloride ranging from 20 to 200 mM. The final adjustment of urine composition is finely tuned along the aldosterone-sensitive distal nephron (ASDN) which includes the distal convoluted tubule and the collecting system (connecting tubule and collecting duct). Sodium reabsorption is predominant along the distal tubule if potassium must be spared, or along the collecting system when large amounts of potassium must be secreted. Nephrotic syndrome is characterized by heavy proteinuria consecutive to a glomerular injury, associated with renal sodium and water retention taking initially place along ASDN and leading to edema.
肾脏通过调节水和溶质的尿排泄以满足身体平衡的需求，在维持“内环境稳定”方面发挥着主要作用。该功能与蛋白质和核酸分解代谢等产生的废物的清除相协调。为了应对这两项主要功能，人类肾脏每天从血浆中生成约180升超滤液，并重新吸收绝大多数滤过的水和溶质，以每日排泄约一到两升尿液，其中钠、钾和氯的浓度范围为20至200毫摩尔。尿液成分的最终调节在醛固酮敏感的远端肾单位（ASDN）中进行精细调节，ASDN包括远端曲管和集合系统（连接小管和集合管）。如果必须保留钾，钠重吸收主要发生在远端小管；当必须分泌大量钾时，则主要发生在集合系统。肾病综合征的特征是肾小球损伤导致大量蛋白尿，伴有最初在ASDN发生的肾性钠和水潴留并导致水肿。
