概括
在老鼠的早期生活中,处理或暴露于寒冷会显著降低上腺酸水平,当他们感到压力时. 在这个关键时期降低体温似乎是影响这种应激反应的关键因素.
科学领域:
- 身体生理学 身体生理学
- 发育生物学 发展生物学
- 压力反应应激反应
背景情况:
- 早期的生活经历可以深刻影响一个生物体的生理发育和应激反应能力.
- 上腺酸反应是压力期间下丘脑-垂体-上腺 (HPA) 轴活动的关键指标.
研究的目的:
- 调查早期生命处理和寒冷暴露对大鼠应激反应的长期影响.
- 为了确定温度降低是否独立于触觉刺激,在压力下影响上腺甲酸耗尽.
主要方法:
- 鼠在出生后的第一个星期被处理或暴露在寒冷中 (没有处理).
- 对照组没有接受生命早期干预.
- 在压力和非压力成年大鼠中测量了上腺酸水平.
主要成果:
- 与对照组相比,暴露于生命早期处理的老鼠在压力下显著降低了上腺 Askorbic 酸.
- 在未经处理的情况下暴露于低温的老鼠也在压力下显著降低了上腺 Askorbic 酸.
- 对照大鼠没有表现出这种显著的减少.
结论:
- 早期接触手持或寒冷,降低体温,使大鼠对压力产生改变的上腺 Askorbic 酸反应.
- 新生儿时期的温度降低可能是调解处理对应力轴发育影响的关键组成部分.
相关概念视频
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02:55Temperature Dependence on Reaction Rate
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The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
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02:19Le Chatelier's Principle: Changing Temperature
Consistent with the law of mass action, an equilibrium stressed by a change in concentration will shift to re-establish equilibrium without any change in the value of the equilibrium constant, K. When an equilibrium shifts in response to a temperature change, however, it is re-established with a different relative composition that exhibits a different value for the equilibrium constant.
To understand this phenomenon, consider the elementary reaction:
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02:28Effect of Temperature Change on Reaction Rate
The Arrhenius equation,
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01:21Entropy Changes Accompanying Specific Processes
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