In rats, intramuscular injection of oxytocin (0.25 nmol/100 g body weight) increased sodium excretion from 19±5 to 120±11 μmol/min. A significant correlation ( p <0.001) was revealed between renal excretion of oxytocin and sodium ions. Under the action of oxytocin, natriuresis was characterized by diminished reabsorption of fluid in the proximal tubule of the nephron attested by elevated lithium clearance rate and from stimulation of V 1a receptors in the cells of thick ascending loop of Henle. Pmp-Tyr(Me)-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH2, a V 1a receptors antagonist, prevented the natriuretic effect of oxytocin.

中文翻译：

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催产素的利钠作用机制

在大鼠中，肌肉注射催产素（0.25 nmol/100 g 体重）使钠排泄量从 19±5 增加到 120±11 μmol/min。在催产素和钠离子的肾脏排泄之间揭示了显着的相关性（p <0.001）。在催产素的作用下，尿钠排泄的特征是肾单位近端小管中液体的重吸收减少，这证明了锂清除率升高和 Henle 厚升袢细胞中 V 1a 受体的刺激。Pmp-Tyr(Me)-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH2 是一种 V 1a 受体拮抗剂，可阻止催产素的利钠作用。