PRR STUDIES ON TRIFLUOPERAZINE-CALMODULIN INTERACTION
钙调蛋白与拮抗剂TFP相互作用的水质子弛豫速率研究

Trifluoperazine (TFP) is an antipsychotic agent which interacts with Calmodulin (CaM) and is a potent antagonist of CaM.The change of water proton relaxation rates (PRR) by TFP bound to CaMis examined.By measuring T-11p for the system TFP-CaM it is possible to obtainthe hydration number of metal ions bound to the binding sites of CaM.As the result of our experiment, when the ratio of TFP:CaM is not larger than 2,the TFP bound to CaM does not change the metal ion coordination sphere. However, the additional TFP reduces the affinity of CaM to metal ions.The third TFP is believed to be bound to the CaM molecule in a different way.This conclusion is supported by the CD spectra of TFP-CaM determined in the far-UV and near-UV region.