Dissociation of saline-induced natriuresis from urea washout in the rat.
Dissociation of saline-induced natriuresis from urea washout in the rat.
复制标题
大鼠体内盐水诱导的尿钠排泄与尿素冲洗的分离。
DOI：
10.1152/ajprenal.1981.241.3.f250
复制
发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Cortell,S
中科院分区：
文献类型：
--
作者：
Gennari,FJ;Johns,C;Caflisch,CR;Cortell,S
髓质尿素冲洗被认为在容量扩张 (VE) 的利尿钠反应中发挥着重要作用。为了检验这一假设，在 VE 的尿钠排泄和非尿钠排泄模型中测量了肾组织溶质成分。分析肾组织成分在缺水、急性 VE、盐水负荷开始时肾动脉压力降至 70 mmHg 的急性 VE 以及盐水负荷 45 分钟后肾动脉压力降至 70 mmHg 的急性 VE（延迟钳夹）。立即钳夹是 VE 的一种非尿钠排泄模型，可防止 VE 诱导的尿素冲刷以及皮质和外髓质中钠和水含量的增加。延迟钳夹是 VE 的利尿钠模型，产生的组织成分模式与立即钳夹非常相似。两种方案中的组织尿素含量没有显着差异，仅注意到钠和水含量的微小差异。因此，在这些实验条件下，VE诱导的尿钠排泄可以与髓质尿素冲刷分离，并且必须调用其他机制来解释钠排泄的增加。
Medullary urea washout has been postulated to play a major role in the natriuretic response to volume expansion (VE). To examine this hypothesis, renal tissue solute composition was measured in a natriuretic and nonnatriuretic model of VE. Renal tissue composition was analyzed during hydropenia, acute VE, acute VE with renal artery pressure reduced to 70 mmHg at the onset of saline loading (immediate clamping), and acute VE with renal artery pressure reduced to 70 mmHg after 45 min of saline loading (delayed clamping). Immediate clamping, a nonnatriuretic model of VE, prevented VE-induced urea washout and the increase in sodium and water content in the cortex and outer medulla. Delayed clamping, a natriuretic model of VE, produced a pattern of tissue composition very similar to immediate clamping. Tissue urea content was not significantly different in the two protocols and only minor differences in sodium and water content were noted. Thus, under these experimental conditions, VE-induced natriuresis can be dissociated from medullary urea washout, and other mechanisms must be invoked to explain the increased sodium excretion.