Development of the receptors to prostaglandin E2 in the rat kidney and neonatal renal functions.
Development of the receptors to prostaglandin E2 in the rat kidney and neonatal renal functions.
复制标题
大鼠肾脏和新生儿肾功能中前列腺素 E2 受体的发育。
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
M. A. Melendez
中科院分区：
文献类型：
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作者：
E. Melendez;Jose L. Reyes;Bruno A. Escalante;M. A. Melendez
抑制前列腺素（PGs）的合成诱导对肾功能的反应是年龄依赖性的。吲哚美辛在成年大鼠中增强对加压素的反应，而在新生大鼠中阻断对脱水的反应。这些差异表明，随着动物的成熟，肾组织对PG的敏感性发生变化。本研究旨在分析发育期大鼠前列腺素E_2受体的特点，并与成年大鼠进行比较。在与氚化PGE 2孵育的皮质和髓质切片中进行结合。结果发现，放射性配体的肾摄取有三个组成部分，第一是内源性肾上腺素的合成，第二是肾小管分泌（仅在皮质），第三是结合到受体位点。我们发现有必要消除前两个组件（与吲哚美辛和p-氨基马尿酸），以实现充分测量的表观亲和力的结合位点PGE 2。在这些条件下，皮质比髓质结合更多的PGE 2（在所有年龄），在新生儿皮质中观察到最高的亲和力。新生大鼠前列腺素E2的合成高于成年大鼠。在体内，吲哚美辛和对乙酰氨基酚阻断新生大鼠脱水的反应，而在断奶和成年大鼠的反应没有改变这些抑制剂的合成的arylandins。我们的研究结果表明，在新生儿的水平衡的调节中的主要作用的三尖杉酯碱。
Inhibition of prostaglandins (PGs) synthesis induces responses on renal function that are age-dependent. Indomethacin in the adult rat potentiates the response to vasopressin whereas in the newborn rat blocks the response to dehydration. These differences suggest that the sensitivity of the renal tissue to PGs changes as the animal matures. This study was designed to analyze the characteristics of the receptors to PGE2 in the developing rat and to compare with that of the adult rat. Binding was performed in cortical and medullary slices incubated with tritiated PGE2. It was found that the renal uptake of the radioactive ligand had three components, the first is the synthesis of endogenous prostaglandins, the second is tubular secretion (only in cortex) and the third is binding to receptor sites. We found it necessary to eliminate the first two components (with indomethacin and p-amino-hippurate) to achieve an adequate measurement of the apparent affinity of the binding sites to PGE2. Under these conditions the cortex bound more PGE2 than the medulla (at all ages) and the highest affinity was observed in the neonatal cortex. Synthesis of prostaglandin E2 was higher in newborn than in adult rats. In vivo, indomethacin and acetaminophen blocked the response of the newborn rat to dehydration whereas in the weaning and adult rat the response was not changed by these inhibitors of the synthesis of prostaglandins. Our results suggest a major role of the prostaglandins in the regulation of the water balance in the neonate.