Scientists claim to have solved the mystery of how stress contributes to memory loss in old age.
4 a4 [* t6 n5 P2 e1 q" { Researchers at Edinburgh University have shown how two receptors in older brains react to the stress hormone cortisol, which has been linked to memory loss in the elderly.) O, U9 K/ \; N6 C& k
科学家们表明他们已经揭开了压力如何导致老年记忆衰退之秘。爱丁堡大学的研究者解释了两个老化的大脑感受器如何对应激激素皮质醇作出反应,这跟老年记忆衰退有关。- E! Y- U7 k5 N! f
The study found that one receptor was activated by low levels of cortisol, which helped memory.1 }/ Q8 i" c" r5 R
研究发现一个感受器被低水平的皮质醇所激活,有助于记忆力。/ ^" O- p) S F y) A# m/ V2 X
However, once levels of the hormone were too high they spilled over on to a second receptor, activating brain processes which contribute to memory impairment., P, N5 ?, b! {) t% N9 n
然而,一旦激素水平过高,就会溢出洒向第二个感受器,激活大脑运作导致记忆障碍。" C. h6 k( u2 `
When the receptor linked to poor memory was blocked, the memory recall problem was reversed.
: W- J% T$ V( ?# o 当连接到健忘的感受器被阻塞,记忆恢复问题就会被改变。中华考试网(www.Examw。com)
K! T% @9 x9 c- A( Y The experiment based on older mice navigating a maze, was published in the Journal of Neuroscience.
( S" X* H8 y) {; S4 T R4 p The research helps explain why too much stress over a prolonged period interferes with the normal processes in storing everyday memories.5 J2 k0 z5 _! [: F' p
This is despite the fact that a little bit of stress can help us better remember emotional memories.' ^' q, j5 z% ~
Dr Joyce Yau said: 'While we know that stress hormones affect memory, this research explains how the receptors they engage with can switch good memory to poorly-functioning memory in old age.'
# S+ R! w0 J& x ] 以大老鼠走迷宫为基础的实验发表在《神经科学杂志》上。% d( X6 g% @4 w5 ]- B; t
该研究解释了为什么长期过多压力会影响日常储存记忆的正常程序。% z% }8 [, Q6 h- Y/ F% } V
尽管一点点压力可以帮助我们更好地进行情绪记忆。
, I, d' |( ?4 n: `1 v5 G/ t Joyce Yau教授说:“我们知道应激激素影响记忆,该研究解释了参与的两个感受器如何在老年时将良好记忆转换成不良记忆。” S6 g7 K. S: P1 M, w7 M9 }6 a
She added that understanding the mechanisms in the brain, which affect memory as we age, will help find ways to combat conditions linked to memory loss.# K3 P8 r5 ^. K2 U0 }- X x& v& q2 N
The study was funded by the Medical Research Council.
. ^4 c; v- s5 K3 r' x 她还说,了解随着年龄老化影响记忆的大脑机制有助于找到与记忆衰退有关问题的解决方法。" D$ q$ m0 f' a5 m/ Q) ~+ l
该研究得到了医学研究理事会的资助。
) c9 s- L$ O* w; X& f Professor Chris Kennard, of the MRC, said: 'This research highlights some interesting, original concepts relating to why memory loss occurs in old age.
4 U6 o/ h3 t; @% f" ? 'With people living ever longer, the MRC is really focusing on research which allows elderly people not just to survive, but also to stay healthy.', v) H! v/ S- u
The researchers are looking at a new chemical compound which blocks an enzyme, known as 11beta-HSD1, which helps produce stress hormones within cells.
$ w9 `* y' |: M# b MRC的教授Chris Kennard说:“这项研究重点介绍了一些原始有趣的观念,即关于为什么老年人记忆会衰退。”; `) A. t6 G& Y. X+ r# B! V" k
“随着人们活的越来越长,MRC真正关注的研究不仅是老年人的生存,而且是他们健康地生活。”! p( }* k D- J6 ]% t
研究人员在关注一种新的化合物11beta-HSD1,它能阻碍一种酶,可以帮助细胞产生应激激素。
4 D4 p( G+ d C+ \# T0 ]5 q They hope this could be used to develop a drug treatment to slow the normal decline in memory associated with ageing, or even improve memory in people who are very old.! B! Y/ ^/ T6 \' E% B
他们希望这种化合物可以用来发明一种药物治疗,放慢由于变老造成的正常记忆衰退速度,甚至提高老年人的记忆力。 |