Koseki C, Kanai Y, Hayashi Y, Ohnuma N, Imai M
Jpn J Pharmacol. 1986 Sep;42(1):27-33. doi: 10.1254/jjp.42.27.
We examined intrarenal localization of receptors for alpha-rat atrial natriuretic polypeptide (alpha-rANP) by injecting [125I]-labeled ligand in vivo into the rat aorta. We found that the receptors for alpha-rANP are distributed also on the vasa recta of the outer and inner medulla in addition to the previously reported sites, i.e., the renal arteries, renal pelvis, glomeruli, and inner medullary tissues including collecting tubules. In the vascular bundle of the outer medulla, the majority of grains was preferentially localized on the arterial vasa recta. The electron microscopic autoradiography of the glomerulus showed that the binding sites were mainly localized on the foot process of the podocyte. Since alpha-rANP injected into the aorta under physiological conditions was bound to the glomerulus and vasa recta in the kidney, the effect of ANP on these binding sites may be important in the mechanism of natriuresis.
我们通过向大鼠主动脉内注射[125I]标记的配体，研究了α-大鼠心房利钠多肽（α-rANP）受体在肾内的定位。我们发现，除了先前报道的部位，即肾动脉、肾盂、肾小球以及包括集合小管在内的髓质内组织外，α-rANP受体还分布在外髓和内髓的直小血管上。在外髓的血管束中，大多数银粒优先定位于动脉直小血管上。肾小球的电子显微镜放射自显影显示，结合位点主要定位于足细胞的足突上。由于在生理条件下注入主动脉的α-rANP会与肾脏中的肾小球和直小血管结合，因此ANP对这些结合位点的作用可能在利钠机制中具有重要意义。
