Postnatal development of carotid body glomus cell response to hypoxia
Postnatal development of carotid body glomus cell response to hypoxia
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DOI：
10.1016/j.resp.2006.01.003
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发表时间：
2006-12-01
影响因子：
2.3
通讯作者：
Carroll, J. L.
中科院分区：
文献类型：
--
作者：
Wasicko, M. J.;Breitwieser, G. E.;Carroll, J. L.
本研究探讨CB球细胞去极化，细胞内钙（[Ca 2 +]（i））和O-2敏感的背景离子电导的大小，可能发挥作用的球细胞的氧敏感性的出生后增加的发育变化从出生后1-3天和11-14天的年龄大鼠分离。采用Fura-2和穿孔膜片全细胞记录技术，同时测定了常氧和缺氧时的[Ca ~（2+）]（i）和膜电位（E-m）。静止E.两个年龄段的正常氧含量相似。与1-3日龄大鼠相比，缺氧引起11- 14日龄大鼠血管球细胞更大的E-m去极化和相应更大的[Ca ~（2+）]（i）反应。两个年龄组对40 mM K+的E-m和[Ca 2 +]（i）反应相同。在常氧条件下，两个年龄组有相似的背景电导。在缺氧条件下（静息膜电位）背景K+电导下降显着更多的细胞从11日龄至14日龄的大鼠相比，细胞从1日龄至3日龄的大鼠。因此，新生儿的血管球细胞具有较低的O-2敏感背景K+电导。这些结果支持这一假设，即出生后成熟的球细胞O-2的敏感性涉及发育调控的背景离子电导的表达和/或O-2的敏感性。(c)2006 Elsevier B. V.保留所有权利。
This study examines developmental changes in CB glomus cell depolarization, intracellular calcium ([Ca2+](i)) and the magnitude of an O-2-sensitive background ionic conductance that may play roles in the postnatal increase in oxygen sensitivity of glomus cells isolated from rats of 1-3 days and 11-14 days postnatal age. Using fura-2 and perforated patch whole cell recordings, we simultaneously measured [Ca2+](i) and membrane potential (E-m) during normoxia and hypoxia. Resting E. in normoxia was similar at both ages. Hypoxia caused a larger E-m depolarization and Correspondingly larger [Ca2+](i) response in glomus cells from 11- to 14-day-old rats compared to 1-3-day-old rats. E-m and [Ca2+](i) responses to 40 mM K+ were identical between the two age groups. Under normoxic conditions both age groups had similar background conductances. Under anoxic conditions (at resting membrane potential) background K+ conductance decreased significantly more in cells from 11- to 14-day-old rats compared to cells from 1- to 3-day-old rats. Glomus cells from newborns therefore have less O-2-sensitive background K+ conductance. These results support the hypothesis that postnatal maturation of glomus cell O-2 sensitivity involves developmental regulation of the expression and/or O-2-sensitivity of background ionic conductances. (c) 2006 Elsevier B.V. All rights reserved.