Goldinger J M, Hong R B, Lee S H, de Bold A J, Hong S K
Proc Soc Exp Biol Med. 1986 Jul;182(3):358-63. doi: 10.3181/00379727-182-42352.
The aim of the present investigation was to test the hypothesis that atrial natriuretic factor (ANF) is secreted into the proximal tubule lumen by the organic anion transport mechanism. The rationale for this hypothesis was the reported probenecid attenuation of the natriuretic effect of ANF. Probenecid is widely regarded as an inhibitor of organic acid transport in the proximal tubule. ANF was prepared in varying degrees of purity ranging from a relatively crude extract to a highly purified form. A commercially available form was also used. All forms were bioassayed using the anesthetized rat and a diuresis and natriuresis was observed in each case which was comparable to literature reports. Interaction of ANF with the organic acid transport system was evaluated using the renal cortical slice technique. Over a wide range of concentrations, there was no effect of ANF on cortical slice accumulation of either p-aminohippurate (PAH), the classical substrate of the organic anion transport system or tetraethylammonium (TEA), a typical organic cation. It is concluded that although ANF may indeed exert its effect at the luminal membranes of the nephron, access to the lumen is not mediated by the organic cation or anion transport system in the proximal tubule.
本研究的目的是验证心房利钠因子（ANF）通过有机阴离子转运机制分泌到近端小管管腔的假说。该假说的依据是，有报道称丙磺舒可减弱ANF的利钠作用。丙磺舒被广泛认为是近端小管中有机酸转运的抑制剂。制备了纯度不同的ANF，从相对粗提物到高度纯化形式。还使用了市售形式。所有形式均用麻醉大鼠进行生物测定，并且在每种情况下均观察到利尿和利钠作用，这与文献报道相当。使用肾皮质切片技术评估ANF与有机酸转运系统的相互作用。在很宽的浓度范围内，ANF对有机阴离子转运系统的经典底物对氨基马尿酸（PAH）或典型有机阳离子四乙铵（TEA）的皮质切片蓄积均无影响。得出的结论是，尽管ANF可能确实在肾单位的管腔膜上发挥作用，但进入管腔并非由近端小管中的有机阳离子或阴离子转运系统介导。
