精神医学62巻4号

2020年04月発行

特集 ベンゾジアゼピン受容体作動薬の問題点と適正使用

ベンゾジアゼピン受容体作動薬依存の薬理学的機序

著者： 芝﨑真裕¹ 森友久¹ 成田年¹

所属機関： ¹星薬科大学薬理学研究室

ページ範囲：P.387 - P.394

抄録　ベンゾジアゼピンは，その安全性から容易に処方され，現代の臨床現場で広く用いられている。しかしながら，長期にわたる連続的な服用により依存症を引き起こすことが知られている。ベンゾジアゼピン系薬物は，α₁，α₂，α₃，およびα₅のいずれのサブユニットから構成されるGABA_A受容体に結合し，薬理作用を発現する。その機序解明にはさまざまなGABA_A受容体の点変異マウスが用いられてきたが，現在ではベンゾジアゼピンの依存症発現にはα₁サブユニットを含有するGABA_A受容体が重要であることが分かってきた。本稿ではベンゾジアゼピン依存に関し，GABA_A受容体を中心としたベンゾジアゼピンの作用機序と薬理学的役割ならびにベンゾジアゼピン依存形成機序について，基礎研究による知見を基盤にして概説する。

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