C-type natriuretic peptide receptors and signaling in rectal gland of Squalus acanthias.
C-type natriuretic peptide receptors and signaling in rectal gland of Squalus acanthias.
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棘角鲨直肠腺中的 C 型利钠肽受体和信号传导。
DOI：
10.1152/ajprenal.1993.264.2.f300
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Silva,P
中科院分区：
文献类型：
--
作者：
Gunning,M;Cuero,C;Solomon,R;Silva,P
最近的证据表明，新描述的利钠肽，C 型利钠肽（CNP），可能是鲨鱼体内利钠肽的循环形式。在鲨鱼中，CNP 在直肠腺中具有主要作用部位，直肠腺响应容量负荷或 CNP 输注的刺激而增加氯化物分泌。因此，我们检查了鲨鱼直肠腺的利尿钠肽受体，并确定了该组织中是否存在鸟苷酸环化酶连接的受体和 CNP 的非鸟苷酸环化酶连接的受体。 CNP 以均匀的高亲和力（解离常数为 78 +/- 11 pM）与直肠腺质膜中的高密度受体（受体密度为 61 +/- 0.7 fmol/mg 蛋白质）结合。通过使用大鼠心房钠尿肽（rANP）作为竞争配体，该群体中出现了两类受体，它们对 CNP 具有相似的亲和力，但对 rANP 具有不同的亲和力。低分子量利钠肽受体特异性肽 des-[Gln116,Ser117,Gly118, Leu119,Gly120]rANP-(102-121) 可与直肠腺中 50% 的受体结合，但即使在微摩尔浓度下也无法与其余 50% 的受体结合。猪脑钠尿肽 (pBNP) 与所有受体的结合亲和力均匀减弱，而不相关的肽，猪血管活性肠肽，不结合这些受体。当肽环打开时，亲和力的显着损失强调了 CNP 环结构完整性的重要性。（摘要截断为 250 字）
Recent evidence suggests that the newly described natriuretic peptide, C-type natriuretic peptide (CNP), may be the circulating form of natriuretic peptide in the shark. In the shark CNP has a major site of action in the rectal gland, which augments chloride secretion in response to stimulation by volume loading or CNP infusion. We therefore examined the shark rectal gland for natriuretic peptide receptors and determined the presence of guanylate cyclase-linked receptors and non-guanylate cyclase-linked receptors for CNP in this tissue. CNP binds with uniform high affinity (dissociation constant of 78 +/- 11 pM) to receptors of high density (receptor density of 61 +/- 0.7 fmol/mg protein) in plasma membranes prepared from the rectal gland. By use of rat atrial natriuretic peptide (rANP) as a competing ligand, two classes of receptors become apparent in this population, both of which have similar affinity for CNP, but different affinities for rANP. The low-molecular-weight natriuretic peptide receptor-specific peptide, des-[Gln116,Ser117,Gly118, Leu119,Gly120]rANP-(102-121), binds to 50% of the receptors in the rectal gland, but fails to bind to the remaining 50% even at micromolar concentrations. Porcine brain natriuretic peptide (pBNP) binds with uniformly diminished affinity to all receptors, whereas the unrelated peptide, porcine vasoactive intestinal peptide, does not bind these receptors. The importance of the integrity of the ring structure of CNP is underlined by the significant loss of affinity when the peptide ring is opened.(ABSTRACT TRUNCATED AT 250 WORDS)