Preparation and animal in vivo study of 131 I-nalepride as a dopamine D2 receptor imaging agent
10.3969/j.issn.1671-8348.2014.02.001
- VernacularTitle:多巴胺D2受体显像剂131I-nalepride的制备和动物体内研究
- Author:
Lizhen WANG
;
Min YANG
;
Donghui PAN
;
Fei CHEN
- Publication Type:Journal Article
- Keywords:
receptor;
dopamine D2;
131 I-nalepride;
imaging agents;
biodistribution
- From:
Chongqing Medicine
2014;(2):129-131,135
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the preparation of 131 I-nalepride and its characters in small animal in vivo ,and to evaluate the feasibility for its application in diagnosing neuropsychiatric disease .Methods s-5-(tributyltin)-N-[(1-ethyl-2-pyrrolidinyl) meth-yl]-2 ,3-dimethoxy-benzamide was used as the labeled precursor .The hydrogen peroxide method was adopted to label131 I-nalepride . The bio-distribution character test in ICR mice was performed .SD rats were performed the blocking experiment and the cerebral au-toradiography .Results The radiolabeled yield and radiochemical purity were over 95% .The results of the bio-distribution character test showed that the striatum had the highest uptake .The striatum to cerebellum uptake radio(ST/CB) reached 111 .87 at 4 h after injection and the maximum ST/CB value of 416 .97 at 12 h after injection .Regional brain autoradiography showed that the optical densities were significantly decreased from 7 .43 ± 0 .86 to 1 .07 ± 0 .18 after injection of 131 I-naleprid(P<0 .05) .These results indi-cated that 131 I-nalepride had specific binding to the dopamine D2 receptor .131 I-nalepride was rapidly uptaken by organs after injec-tion .The initial uptake in liver and kidney were higher and the % ID/g values were 14 .82 ± 3 .88 and 10 .28 ± 1 .65 receptively .The tracer was cleared out from the organ quite rapidly .Conclusion 131 I-nalepride has the high affinity and specificity to dopamine D2 receptor ,which could be used as the EPECT imaging agent of dopamine D2 receptors and as a tool drug to screen and evaluate the affinity of other antipsychotic agents to dopamine D2 receptors .
