中文摘要：

目的 探讨多巴胺D2受体显像剂（s）-（-）-N-（1-烯丙基吡咯烷-2-氨基甲基）-5-（3-氟）-2,3-二甲氧基苯甲酰胺（18F-Fallypride）靶向显像胰岛细胞的可行性.方法 （1）细胞学实验：确定适宜的胰岛细胞密度（15×10^3个细胞/孔）和18F-Fallypride放射性活度（3.70 kBq）.将上述胰岛细胞与18F-Fallypride共同孵育1h,测定其细胞摄取率[细胞计数/（上清液计数＋细胞计数）×100％].相同实验条件下按多巴胺抑制剂氟哌利多的浓度（1.0×10^-6、4.0×10^-6、2.0× 10^-5、1.0× 10^-4、5×10^-4和1.0×10^-3 mol/L）分6个抑制组并设定空白对照组.加入氟哌利多后30 min,每组分别加入3.70 kBq ^18F-Fallypride,计算各组^18F-Fallypride摄取率.（2）组织放射自显影实验：取正常ICR小鼠18只,分为6组.A组为结合实验组,尾静脉注射^18 F-Fallypride（55±5）MBq/只.B-F组为抑制组,静注18F-Fallypride前30 min先给予氟哌利多,剂量分别为0.2、0.4、0.6、0.8和1.0 mg/kg.注射后处死动物,行放射自显影检测胰腺组织灰度.各组总体趋势比较采用单因素方差分析,组间两两比较采用最小显著差异t检验.结果 （1）体外胰岛细胞^18 F-Fallypride摄取率为（18.40±1.21）％.各抑制组胰岛细胞摄取率随着氟哌利多浓度增加而减少,分别为（16.11±1.37）％、（15.76±0.99）％、（13.90±1.02）％、（8.86±0.73）％、（7.26±0.62）％和（6.92±0.58）％（F=50.01,P＜0.01）.当氟哌利多浓度为1.0× 10^-4 mol/L时胰岛细胞摄取率最低,抑制率为51.85％.（2）A组小鼠胰腺组织灰度为1.21×10^6光强度单位（DLU）/mm^2,B-F组灰度随着抑制剂浓度增加而下降,分别为0.93× 10^6、0.77× 10^6、0.59× 10^6、0.32×10^6和0.25× 10^6 DLU/mm^2.结论 18F-Fallypride可与胰岛细胞多巴胺受体特异结合,效率高,可能是胰岛细胞显像的潜在示踪剂.

英文摘要：

Objective To evaluate the feasibility of dopamine D2 receptor imaging agent （s）-（-）-N-（1-allylpyrrolidine-2-N-methyl）-5-（3-18F）-2,3-dimethoxy Benzamide （18F-Fallypride） for targeting islet cell imaging.Methods （1） Cytology experiment：Islet cells of 15×10^3cells/well were incubated with 3.70 kBq/well 18F-Fallypride for 1 h and the uptake rate of cells was calculated （cell counts/（supernatant counts ＋ cell counts）× 100%）.Under the same experiment conditions,6 inhibiting groups were administrated with different concentration of dopamine inhibitors droperidol （1.0×10^-6,4.0×10^-6,2.0× 10^-5,1.0× 10^-4,5.0× 10^-4 and 1.0× 10^-3 mol/L,respectively）.After 30 min,3.70 kBq of 18F-Fallypride was added to each inhibiting group,and the inhibiting rate was calculated.（2） Autoradiography：18 normal ICR mice were divided into 6 groups.For group A,ICR mice were injected with ^18F-Fallypride （55 ± 5） MBq/mice through tail vein.For the other 5 inhibiting groups （group B-F）,ICR mice were injected with different doses of droperidol （0.2,0.4,0.6,0.8 and 1.0 mg/kg,respectively）,and after 30 min ^18F-Fallypride were injected through tail vein.Ten minutes later,pancreas of ICR mice was taken for preparation of tissue section autoradiography.The data were analyzed by one-way analysis of variance and the least significant difference t test.Results （1） The 18F-Fallypride uptake rate of control group was （18.40± 1.21） %.The uptake rates of inhibiting groups were （16.11±1.37）%,（15.76±0.99）%,（13.90±1.02）%,（8.86±0.73）%,（7.26±0.62）% and （6.92±0.58）%,respectively,which decreased with the decreasing concentration of droperidol （F=50.01,P〈0.01）.When the concentration of droperidol was 1.0× 10^-4 mol/L,the uptake rate reached the lowest with inhibiting rate of 51.85%.（2） The autoradiography showed that the pancreas gray scale value of group A was 1.21×10^6 digital light units （DLU）/mm^2.The pancreas gray scale value of groups B t