• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>American Journal of Physiology >Long-term hypoxia alters ovine fetal endocrine and physiological responses to hypotension.
【24h】

Long-term hypoxia alters ovine fetal endocrine and physiological responses to hypotension.

机译：长期缺氧会改变绵羊胎儿内分泌和对低血压的生理反应。

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

Exposure to long-term hypoxia (LTH) results in altered cortisol responses in the ovine fetus. The present study was designed to test the hypothesis that LTH alters adrenal responsiveness to fetal hypotension. Pregnant ewes were maintained at high altitude (3,820 meters) from day 30 of gestation. Normoxic control and LTH fetuses were catheterized on day 132 of gestation. In the LTH group, maternal Po(2) was maintained comparable to that observed at altitude ( approximately 60 mmHg) by nitrogen infusion through a tracheal catheter. On day 137, fetuses received a 5-h saline infusion followed by infusion of sodium nitroprusside to reduce fetal arterial pressure by 30-35% for 10 min. The study was repeated on day 139 of gestation with a continuous cortisol infusion (10 microg/min). Hypothalamic and pituitary tissues were collected from additional fetuses for assessment of glucocorticoid receptors. During the saline infusion in response to hypotension, plasma ACTH increased over preinfusion mean values in both groups (P < 0.05). Plasma cortisol concentrations increased in both groups concomitant with increased ACTH secretion. However, peak values in the LTH fetuses were significantly higher compared with controls (P < 0.05). During the cortisol infusion, the ACTH response was eliminated in both groups, with ACTH levels significantly lower in the LTH group (P < 0.05). Glucocorticoid receptor binding was not different between groups. These results demonstrate an enhanced cortisol response to hypotension in LTH fetuses that does not appear to be the result of an increase in negative feedback sensitivity of the hypothalamic-pituitary-adrenal axis.
机译：长期缺氧（LTH）暴露会导致绵羊胎儿的皮质醇反应改变。本研究旨在测试LTH改变肾上腺对胎儿低血压反应的假设。从妊娠第30天起，母羊就保持在高海拔（3820米）。妊娠第132天，将正常氧控制和LTH胎儿置入导管。在LTH组中，通过通过气管导管充氮，孕妇Po（2）维持与在海拔高度（约60 mmHg）观察到的水平相当。在第137天，胎儿接受了5小时的生理盐水注入，随后输注了硝普钠以使胎儿动脉压降低30-35％，持续10分钟。在妊娠的第139天，连续输注皮质醇（10 microg / min），重复该研究。从其他胎儿收集下丘脑和垂体组织，以评估糖皮质激素受体。在因低血压而输注盐水期间，两组血浆血浆ACTH均高于输注前平均值（P <0.05）。两组血浆血浆皮质醇浓度增加，同时ACTH分泌增加。但是，与对照组相比，LTH胎儿的峰值明显更高（P <0.05）。在皮质醇输注过程中，两组的ACTH反应均被消除，LTH组的ACTH水平显着降低（P <0.05）。两组之间糖皮质激素受体的结合没有差异。这些结果表明，皮质激素对LTH胎儿低血压的反应增强，这似乎不是下丘脑-垂体-肾上腺轴负反馈敏感性增加的结果。

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