• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>American Journal of Physiology >Regulation of renal NaPi-2 expression and tubular phosphate reabsorption by growth hormone in the juvenile rat.
【24h】

Regulation of renal NaPi-2 expression and tubular phosphate reabsorption by growth hormone in the juvenile rat.

机译：幼年大鼠生长激素对肾NaPi-2表达和肾小管磷酸盐重吸收的调节。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Growth hormone (GH) is an important factor in the developmental adaptation to enhance P(i) reabsorption; however, the nephron sites and mechanisms by which GH regulates renal P(i) uptake remain unclear and are the focus of the present study. Micropuncture experiments were performed after acute thyroparathyroidectomy in the presence and absence of parathyroid hormone (PTH) in adult (14- to 17-wk old), juvenile (4-wk old), and GH-suppressed juvenile male rats. While the phosphaturic effect of PTH was blunted in the juvenile rat compared with the adult, suppression of GH in the juvenile restored fractional P(i) excretion to adult levels. In the presence or absence of PTH, GH suppression in the juvenile rat caused a significant increase in the fractional P(i) delivery to the late proximal convoluted (PCT) and early distal tubule, so that delivery was not different from that in adults. These data were confirmed by P(i) uptake studies into brush-border membrane (BBM) vesicles. Immunofluorescence studies indicate increased BBM type IIa NaP(i) cotransporter (NaPi-2) expression in the juvenile compared with adult rat, and GH suppression reduced NaPi-2 expression to levels observed in the adult. GH replacement in the [N-acetyl-Tyr(1)-d-Arg(2)]-GRF-(1-29)-NH(2)-treated juveniles restored high NaPi-2 expression and P(i) uptake. Together, these novel results demonstrate that the presence of GH in the juvenile animal is crucial for the early developmental upregulation of BBM NaPi-2 and, most importantly, describe the enhanced P(i) reabsorption along the PCT and proximal straight nephron segments in the juvenile rat.
机译：生长激素（GH）是发育适应中增强P（i）重吸收的重要因素;然而，GH调节肾P（i）摄取的肾单位和机制尚不清楚，这是本研究的重点。在成人（14至17周龄），少年（4周龄）和GH抑制的幼年雄性大鼠中，在有无甲状旁腺激素（PTH）的情况下进行急性甲状腺甲状旁腺切除术后进行微穿刺实验。尽管与成年幼体相比，PTH的磷酸化作用减弱，但幼体中GH的抑制将P（i）的分数排泄恢复至成年水平。在存在或不存在PTH的情况下，幼年大鼠中的GH抑制导致向晚期近端旋绕（PCT）和早期远端小管的P（i）递送分数显着增加，因此递送与成人没有区别。这些数据已通过P（i）对刷状边界膜（BBM）囊泡的摄取研究得到证实。免疫荧光研究表明，与成年大鼠相比，少年中BBM IIa型NaP（i）共转运蛋白（NaPi-2）表达增加，而GH抑制将NaPi-2表达降低到成年大鼠中观察到的水平。 GH替换[N-乙酰基-Tyr（1）-d-Arg（2）]-GRF-（1-29）-NH（2）处理的少年中恢复了高的NaPi-2表达和P（i）吸收。总之，这些新颖的结果表明，幼小动物体内GH的存在对于BBM NaPi-2的早期发育上调至关重要，最重要的是，它描述了沿PCT和近端笔直肾单位段增强的P（i）重吸收。幼鼠。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号