Presystemic influences on thirst, salt appetite, and vasopressin secretion in the hypovolemic rat.
Presystemic influences on thirst, salt appetite, and vasopressin secretion in the hypovolemic rat.
复制标题
系统前对低血容量大鼠口渴、盐食欲和加压素分泌的影响。
DOI：
10.1152/ajpregu.00595.2006
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Stricker,EdwardM
中科院分区：
文献类型：
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作者：
Smith,CarrieA;Curtis,KathleenS;Smith,JamesC;Stricker,EdwardM
本研究探讨了系统前信号对非扩张性低血容量大鼠口渴、盐食欲和加压素（VP）分泌的影响。向大鼠注射30%聚乙二醇（PEG）溶液，禁食和禁水过夜，然后允许饮用水、0.15 M NaCl或0.30 M NaCl。PEG治疗，产生30-40%的血浆容量赤字，引起快速摄入的初始回合的饮用水，但大鼠消耗更多的0.15 M NaCl比水或0.30 M NaCl。在考虑为什么喝水或浓盐水摄入后饮水停止得更快时，似乎相关的是，在初始发作期间观察到全身血浆Na+浓度变化很小或没有变化，并且低血容量的部分修复是相当的，无论消耗哪种液体。在饮用0.15 M NaCl的大鼠中，胃排空最快，胃和小肠中摄入液体的总体积最大。这些和其他观察结果与以下假设一致，即低血容量大鼠的液体摄入受到胃和近端小肠扩张的抑制，并且稀释或浓缩的液体进入小肠的运动提供了另一种分别抑制口渴或盐食欲的系统前信号。另一方面，在PEG处理的大鼠中，没有观察到水或生理盐水消耗对VP分泌的早期影响，与脱水大鼠中最近的研究结果相反。因此，在低血容量期间，对液体摄入和VP分泌的控制是相似的，但不完全相同。
The present studies investigated the influence of presystemic signals on the control of thirst, salt appetite, and vasopressin (VP) secretion in rats during nonhypotensive hypovolemia. Rats were injected with 30% polyethylene glycol (PEG) solution, deprived of food and water overnight, and then allowed to drink water, 0.15 M NaCl, or 0.30 M NaCl. The PEG treatment, which produced 30–40% plasma volume deficits, elicited rapid intakes in an initial bout of drinking, but rats consumed much more 0.15 M NaCl than water or 0.30 M NaCl. In considering why drinking stopped sooner when water or concentrated saline was ingested, it seemed relevant that little or no change in systemic plasma Na+concentration was observed during the initial bouts and that the partial repair of hypovolemia was comparable, regardless of which fluid was consumed. In rats that drank 0.15 M NaCl, gastric emptying was fastest and the combined volume of ingested fluid in the stomach and small intestine was largest. These and other observations are consistent with the hypothesis that fluid ingestion by hypovolemic rats is inhibited by distension of the stomach and proximal small intestine and that movement of dilute or concentrated fluid into the small intestine provides another presystemic signal that inhibits thirst or salt appetite, respectively. On the other hand, an early effect of water or saline consumption on VP secretion in PEG-treated rats was not observed, in contrast to recent findings in dehydrated rats. Thus the controls of fluid ingestion and VP secretion are similar but not identical during hypovolemia.