外源氧是需要在脑缺血下进行前列腺诱导的,这是一个新的调节机制的证据
Drew R Seeger1, Brennon Schofield1, Derek Besch1
1Department of Biomedical Sciences, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND, USA.
Journal of lipid research
|October 2, 2023
概括
在缺血期间大脑的前列腺体 (PG) 生产受到氧气供应的调节,而不仅仅是酸. 这一发现挑战了传统的理解,并强调氧是低氧条件下PG合成的关键因素.
科学领域:
- 神经科学是一个神经科学.
- 生物化学 生物化学
- 缺血症研究 缺血症研究
背景情况:
- 大脑前列腺素 (PG) 水平,包括前列腺素,前列腺素和血栓素,在缺血期间迅速增加.
- 这种增加传统上归因于脂酶激活和阿拉基酸 (20:4n6) 释放的循环氧化酶 (COX) 酶.
- 在这个过程中,氧气的作用被忽视了,氧气是另一个重要的COX基质.
研究的目的:
- 研究氧气供应在脑缺血期间调节前列腺质 (PG) 生产中的作用.
- 重新评估在缺血病条件下对PG上调的既定机制.
主要方法:
- 分析小鼠大脑的前列腺体 (PG),自由阿拉基酸 (20:4n6) 和氧气水平在各种时间点后缺血.
- 在切之前,利用头部聚焦的微波辐射 (MW) 在位失活酶.
- 在不同的条件下比较PG水平:正常缺血症,MW治疗缺血症和随着或没有随后的氧气暴露而出现的无氧状况.
主要成果:
- 缺血性大脑中的氧气水平半衰期很短 (5.32 ± 0.45 秒),在 12 秒内变得无法检测.
- 在30秒的缺血后没有观察到自由20:4n6或PG的显著变化;尽管自由20:4n6增加了50-100倍,但在2分钟和10分钟内PG水平保持不变.
- 前列腺素 (PG) 水平只有在缺血之后进行了提供氧气的骨切割时才显著增加 (~30倍),并且在无氧大脑中暴露氧气时发生了PG诱导.
结论:
- 在脑缺血期间,氧气的可用性是前列腺质 (PG) 生产的关键调节因素.
- 这些发现挑战了传统的观点,即只有阿拉基酸的可用性驱动了缺血中的PG上调.
- 需要进一步的研究来阐明组织氧度在调节循环氧化酶 (COX) 和PG通路中的生理意义.
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