Gerzer R, Weil J, Strom T, Müller T
Klin Wochenschr. 1986;64 Suppl 6:21-6.
Atrial natriuretic factor (ANF) acts through specific receptors at its target tissues. Receptor-occupancy by ANF induces activation of particulate guanylate cyclase, increased cyclic GMP formation and also inhibition of adenylate cyclase which results in a decrease of cyclic AMP formation. These second messenger systems appear to mediate the effects of ANF in target tissues. Following receptor-mediated activation of particulate guanylate cyclase, cyclic GMP is extruded from the cells, which leads to elevated cyclic GMP levels in plasma and urine in man, whereas cyclic AMP levels remain unchanged. Since cyclic GMP has a much longer half-life than ANF, it is more sensitive as a marker for ANF release than ANF itself, which has a half-life of just a few minutes. Since cyclic GMP is excreted into urine, determinations of urine cyclic GMP can also allow conclusions about the ANF system when blood sampling is impractical. Thus, cyclic GMP and not cyclic AMP is a sensitive biological marker for ANF.
心房利钠因子（ANF）通过其靶组织中的特定受体发挥作用。ANF与受体结合会诱导颗粒型鸟苷酸环化酶激活，增加环鸟苷酸（cGMP）的生成，同时抑制腺苷酸环化酶，导致环腺苷酸（cAMP）生成减少。这些第二信使系统似乎介导了ANF在靶组织中的作用。在受体介导的颗粒型鸟苷酸环化酶激活后，cGMP从细胞中排出，这导致人体血浆和尿液中的cGMP水平升高，而cAMP水平保持不变。由于cGMP的半衰期比ANF长得多，作为ANF释放的标志物，它比半衰期仅为几分钟的ANF本身更敏感。由于cGMP会排泄到尿液中，在无法进行血液采样时，测定尿cGMP也可以对ANF系统做出推断。因此，cGMP而非cAMP是ANF的敏感生物学标志物。
