Maack T
Department of Physiology, Cornell University Medical College, New York, New York, USA.
Kidney Int. 1996 Jun;49(6):1732-7. doi: 10.1038/ki.1996.257.
Atrial natriuretic factor (ANF) is a 28 amino acid polypeptide hormone secreted mainly by the heart atria in response to atrial stretch. ANF acts on the kidney to increase sodium excretion and GFR, to antagonize renal vasoconstriction, and to inhibit renin secretion. In the cardiovascular system, ANF antagonizes vasoconstriction, and shifts fluid from the intravascular to the interstitial compartment. In the adrenal gland, ANF is a powerful inhibitor of aldosterone synthesis. ANF participates importantly in the natriuretic response to acute and chronic volume overload. ANF's property of shifting fluid from the vascular to the interstitial compartment acts as a buffering device, guarding against excessive plasma volume expansion in face of an increased total extracellular fluid volume. ANF is also a physiological modulator of GFR, and mediates nephron hyperfiltration and natriuresis when salt excretion is threatened by a reduction in the number of nephrons. Guanylyl cyclase (GCA) receptors mediate the effects of ANF by generating cGMP. Clearance receptors remove ANF from the circulation by receptor-mediated endocytosis, and serve as a hormone buffer system to impede large inappropriate fluctuations in plasma levels of ANF. The specific structure-function-dynamics relationships of these receptors serve to modulate the role of ANF in pressure-volume homeostasis.
心房利钠因子（ANF）是一种由28个氨基酸组成的多肽激素，主要由心房肌细胞在心房扩张时分泌。ANF作用于肾脏，增加钠排泄和肾小球滤过率（GFR），拮抗肾血管收缩，并抑制肾素分泌。在心血管系统中，ANF拮抗血管收缩，并使液体从血管内转移到组织间隙。在肾上腺，ANF是醛固酮合成的强效抑制剂。ANF在急性和慢性容量超负荷的利钠反应中起重要作用。ANF将液体从血管转移到组织间隙的特性起到了缓冲作用，可防止在细胞外液总量增加时血浆容量过度扩张。ANF也是GFR的生理调节因子，当肾单位数量减少威胁到盐排泄时，它介导肾单位超滤过和利钠作用。鸟苷酸环化酶（GCA）受体通过生成环磷酸鸟苷（cGMP）介导ANF的作用。清除受体通过受体介导的内吞作用从循环中清除ANF，并作为一种激素缓冲系统，以阻止ANF血浆水平出现大幅不当波动。这些受体特定的结构 - 功能 - 动力学关系有助于调节ANF在压力 - 容量稳态中的作用。
