調(diào)查稱，美國26％的中小學(xué)生在進(jìn)入青春期之后學(xué)習(xí)成績出現(xiàn)下降,。3月19日的《科學(xué)》Science雜志報道說,。這并非玩笑：當(dāng)青春期來臨時，人們實際上學(xué)習(xí)能力也會下降,。 這一學(xué)習(xí)能力下降的階段已有充分的證明,，但現(xiàn)在，研究人員已經(jīng)在小鼠中找到了在這些青春發(fā)動期動物體內(nèi)的可減緩學(xué)習(xí)過程的某些細(xì)胞學(xué)和分子學(xué)的基礎(chǔ),。
美國紐約州立大學(xué)Hui Shen及其同僚結(jié)合高倍顯微鏡,、藥理學(xué)、生理學(xué)及行為測試等手段發(fā)現(xiàn)了某些受體復(fù)合物,，這些復(fù)合物在青春期的時候會出現(xiàn)在脊髓的突觸周圍,，從而影響海馬體的功能并降低學(xué)習(xí)的能力,。
這些特殊的GABAA 和 GABAR受體會在小鼠的青春期出現(xiàn)，并干擾輸送到海馬體的信號,，而這些信號對神經(jīng)元之間的交流是至關(guān)重要的,。 因此，這些年輕的小鼠在實驗室的測試中會出現(xiàn)空間學(xué)習(xí)能力下降的跡象,。 研究人員還發(fā)現(xiàn),，一種特別的應(yīng)激類固醇THP（它在正常時的作用是損害老年人的學(xué)習(xí)能力）實際上能夠逆轉(zhuǎn)這一青春期所驅(qū)動的學(xué)習(xí)能力下降的缺陷。研究人員提示,，該應(yīng)激類固醇可用來改變在青春期功能減緩的神經(jīng)元的功能,。 (生物谷Bioon.com)
APAM：超重男孩青春期可能遲到
PNAS：酒精使青春期變得更加瘋狂
Nature Immunology：讓精疲力竭的免疫細(xì)胞恢復(fù)青春
生物谷推薦原文出處：
Science DOI: 10.1126/science.1184245
A Critical Role for Alpha4-Beta-Delta GABAA Receptors in Shaping Learning Deficits at Puberty in Mice
Hui Shen,1,* Nicole Sabaliauskas,1,2,* Ang Sherpa,1,3 André A. Fenton,1,3,4 Armin Stelzer,1,3,4 Chiye Aoki,2 Sheryl S. Smith1,3,4,
The onset of puberty defines a developmental stage when some learning processes are diminished, but the mechanism for this deficit remains unknown. We found that, at puberty, expression of inhibitory 4β -aminobutyric acid type A (GABAA) receptors (GABAR) increases perisynaptic to excitatory synapses in CA1 hippocampus. Shunting inhibition via these receptors reduced N-methyl- D-aspartate receptor activation, impairing induction of long-term potentiation (LTP). Pubertal mice also failed to learn a hippocampal, LTP-dependent spatial task that was easily acquired by –/– mice. However, the stress steroid THP (3OH-5[β]-pregnan-20-one), which reduces tonic inhibition at puberty, facilitated learning. Thus, the emergence of 4β GABARs at puberty impairs learning, an effect that can be reversed by a stress steroid.
1 Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA.
2 Center for Neural Science, New York University, 4 Washington Place, New York, NY 10003, USA.
3 Program in Neural and Behavioral Science, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA.
4 The Robert F. Furchgott Center for Neural and Behavioral Science, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA.
