D‐[35S(U)]Inositol 1,4,5‐trisphosphorothioate, a novel radioligand for the inositol 1,4,5‐trisphosphate receptor Complex binding to rat cerebellar membranes

FEBS Letters

Challiss, R.A.John²  Potter, Barry V.L.¹  Nahorski, Stefan R.²  Smith, Susan M.² 

[1] School of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK;Department of Pharmacology and Therapeutic, University of Leicester, Leicester, LE1 9HN, UK

关键词: Inositol 1;    4;    5-trisphosphate;    Inositol 1;    4;    5-trisphosphorothioate;    Inositol 1;    4;    5-trisphosphate receptor;   

DOI  :  10.1016/0014-5793(91)80368-D

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

D-[³⁵S(U)]mya-inositol 1,4,5-trisphosphorothioate ([³⁵S]InsPS₃), a synthetic, metabolically stable analogue of inositol 1,4,5-trisphosphate (InsP₃) binds with high affinity (K_a 58.6±9.1 nM) to rat cerebellar revealing a high density of specific binding sites (D _max 21.5±2.1 pmol/mg of protein). Comparison with [³H]InsP₃ binding reveals a higher density of sites labelled by [³⁵S]InsPS₃ and complex competition curves for displacement of specific [³⁵S]insPS₃ by InsP₃. The results suggests that [³⁵S]InsPS₃ labels two sites in rat cerebellar membranes with equal affinity: the InsP₃ receptor and a site that displays low affinity for InsP₃.

【 授权许可】

Unknown