Agonist pharmacology of the neuronal α7 nicotinic receptor expressed in Xenopus oocytes

FEBS Letters

Lunt, G.G.¹  Wonnacott, S.¹  Amar, M.¹  Thomas, P.¹  Johnson, C.¹ 

[1] Department of Biochemistry, University of Bath, Bath BA2 7AY, UK

关键词: Neuronal nicotinic receptor;    Nicotinic agonist;    (+)-Anatoxin-a;    Nicotine;    α-Bungarotoxin;    Xenopus oocyte;    nAChR;    nicotinic acetylcholine receptor;    αBgt;    α-bungarotoxin;    DMPP;    1;    1-dimethyl-4-phenylpiperazinium iodide;    AMP MeI;    1-acetyl-4-methylpiperazine methiodide;   

DOI  :  10.1016/0014-5793(93)81005-K

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The potencies and efficacies of seven agonists at chick α7 nicotinic receptors expressed in Xenopus oocytes were determined by whole cell recording. (+)-Anatoxin-a was the most potent agonist (EC₅₀ = 0.58 μM) and acetylcholine was the least potent (EC₅₀ = 320 μM). The rank order of agonist potencies was: (+)-anatoxin-a ⪢ cytisine > (−)-nicotine > (+)-nicotine > DMPP > 1-acetyl-4-methylpiperazine methiodide > acetylcholine. DMPP evoked only very small currents: comparison of maximally effective agonist concentrations showed that DMPP was only one-fifth as efficacious as other agonists. Previously published IC₅₀ values for rat brain [¹²⁵I]α-bungarotoxin sites show a similar agonist profile, and the identity of homo-oligomeric α7 receptors with native α-bungarotoxin-sensitive neuronal nicotinic receptors is discussed.

【 授权许可】

Unknown