龟脑的强抗氧化功能可能与龟类的长寿相关

Improved Antioxidative Efficacy of Turtles May be of Importance for Their Enhanced Longevity

龟脑防御缺氧和再供氧伤害的过程可能与龟类的长寿相关。研究表明龟体内有特别的保护各种离子通道和受体功能的机制,龟脑在缺氧条件下,可以抑制兴奋性神经递质的毒害作用,其机制也许是通过维持多巴胺和谷氨酸的释放与再吸收之间的平衡来实现的。此外,它通过胞外的γ-氨基丁酸(GABA)浓度的持续升高和其受体密度的相应增加而抵抗活性氧基团的生成,并且免受其伤害。这样的机制可能在缺氧和再供氧的状态下被选择性的激活,因此龟类可作为研究衰老和抗衰老生理机制的动物模型。

The capability of preventing oxidative stress in turtles is found enhanced and reviewed. The anoxic turtle brain can avoid excitatory neurotransmitter toxicity by regulating a balance between dopamine and glu-tamate content. In the anoxic turtle brain inhibitory tone seemed to be strengthened through an increase in extracellular GABA and the density of GABA receptors. The turtles seem to developed an enhanced capability in protecting against reactive oxygen species and their damages. Turtles may thus serve as a useful model to investigate mechanisms for efficient protection and rescue for animal tissues during aging.