Manevich E M, Köiv A, Järv J, Molotkovsky J G, Bergelson L D
Tartu State University, Estonian SSR.
FEBS Lett. 1988 Aug 15;236(1):43-6. doi: 10.1016/0014-5793(88)80282-5.
The previously suggested method of following ligand-receptor interactions by measuring ligand-induced changes in membrane fluidity [(1986) FEBS Lett. 194, 313-316] was employed to study the binding of specific ligands of the muscarinic receptor to rat brain membrane fragments containing a fluorescent analogue of phosphatidylcholine (APC) as a membrane probe. Upon addition of carbachol and atropine in low concentrations the fluorescence polarization of the APC-labeled membranes decreased significantly demonstrating that binding of these ligands to the muscarinic receptor increases the fluidity of its lipid environment. The fluidity changes were specific, concentration-dependent and saturable. In comparison with radioligand assays the fluorescent lipid probe method proved to be much more sensitive but the Kd values obtained by the two methods differed considerably.
采用先前提出的通过测量配体诱导的膜流动性变化来追踪配体 - 受体相互作用的方法[（1986年）《欧洲生物化学学会联合会快报》194，313 - 316]，研究毒蕈碱受体的特异性配体与含有磷脂酰胆碱荧光类似物（APC）作为膜探针的大鼠脑膜片段的结合。加入低浓度的卡巴胆碱和阿托品后，APC标记膜的荧光偏振显著降低，表明这些配体与毒蕈碱受体的结合增加了其脂质环境的流动性。流动性变化具有特异性、浓度依赖性且可饱和。与放射性配体测定相比，荧光脂质探针法被证明更为灵敏，但两种方法获得的Kd值差异很大。
