Heisler S, Tallerico-Melnyk T, Yip C, Schimmer B P
Unité de Biorégulation Cellulaire, Centre Hospitalier de l'Université Laval, Sainte-Foy, Quebec, Canada.
Endocrinology. 1989 Nov;125(5):2235-43. doi: 10.1210/endo-125-5-2235.
The effects of atrial natriuretic peptide (ANP) on adrenocortical fasciculata cells were examined in the ACTH-responsive Y-1 mouse adrenocortical tumor cell line. Y-1 cell membranes rapidly bound [125I]ANP, with equilibrium binding (22 C) reached within 45 min. Binding of [125I]ANP was inhibited in a concentration-dependent manner by unlabeled ANP and atriopeptin-I (IC50, approximately 1.2 X 10(-9) and 1.6 X 10(-8) M, respectively), but not by C- or N-terminal-deleted ANP fragments, ACTH, or arginine vasopressin (up to 10(-6) M). Scatchard analysis revealed a single class of high affinity binding sites with a Kd of 1.6 X 10(-10) M and a binding capacity of 560 fmol/mg protein. Photo-affinity labeling demonstrated the specific binding of ANP to two protein entities of 130 and 63 kDa. ANP stimulated both cGMP synthesis and secretion from Y-1 cells (EC50, approximately 3.5 X 10(-9) M). Release of the nucleotide was inhibited by probenecid (IC50, approximately 5 X 10(-5) M). The atrial peptide partially inhibited ACTH-stimulated cAMP formation (IC50, approximately 10(-8) M) and partially antagonized basal and ACTH-stimulated steroidogenesis. The data demonstrate the presence in Y-1 cells of specific and saturable ANP receptors, activation of which leads to changes in cyclic nucleotide metabolism and inhibition of steroidogenesis.
在促肾上腺皮质激素（ACTH）反应性Y-1小鼠肾上腺皮质肿瘤细胞系中研究了心钠素（ANP）对肾上腺皮质束状带细胞的作用。Y-1细胞膜能快速结合[125I]ANP，45分钟内达到平衡结合（22℃）。未标记的ANP和心房肽-I以浓度依赖的方式抑制[125I]ANP的结合（IC50分别约为1.2×10^(-9)和1.6×10^(-8)M），但C端或N端缺失的ANP片段、ACTH或精氨酸加压素（高达10^(-6)M）则无此作用。Scatchard分析显示存在一类高亲和力结合位点，Kd为1.6×10^(-10)M，结合容量为560fmol/mg蛋白质。光亲和标记表明ANP与130kDa和63kDa的两种蛋白质特异性结合。ANP刺激Y-1细胞合成cGMP并分泌（EC50约为3.5×10^(-9)M）。核苷酸的释放受到丙磺舒的抑制（IC50约为5×10^(-5)M）。心房肽部分抑制ACTH刺激的cAMP形成（IC50约为10^(-8)M），并部分拮抗基础和ACTH刺激的类固醇生成。数据表明Y-1细胞中存在特异性和可饱和的ANP受体，其激活导致环核苷酸代谢改变并抑制类固醇生成。
