To investigate the preparation of radioiodinated salidroside and its cell uptake in SH-SY5Y and its biodis-tribution in mice

salidroside was labeled with 131I using the chloramine-T method and the radiolabeled compound was characterized by polyamide TLC

in which the substratum of Vtrichoromethane: Vmethanol: Vacetone: Vwater=6:3:1:1 was used as the developing agent. The uptake of 131I-salidroside in human neuroblast cells(SH-SY5Y) and mammary can-cer cells(MCF-7) was then measured and the biodistribution studies were carried out in KM mice. At different time(5

10

30

60

120

and 240 min) after radiopharmaceutical i.v. administration (1.85MBq 131I-salidroside /mouse)

the animals were sacrificed (n=5 animals for each time). Blood and the interested tissues samples were collected

washed

weighted and counted. The percent injected dose per gram (%ID/g) was calculated for each sample. The labeling yield of 131I-salidroside was 98% and its RCPs were 98.5%

97.3%

and 97.1% after 1

4 and 20 days

respectively. In SH-SY5Y

131I-salidroside uptake kept at a low level of around 0.035% from 0.5 to 4h

while in MCF-7 a slightly higher uptake of 0.1% was reached. Biodistribution in mice demonstrated that 131I-salidroside was metabolized mainly in liver and rapid elimination through kidney

in which the % ID/g were 7.71% and 11.31% at 5 min

0.36% and 0.3% at 4h

respectively. Rapid clearance was also found in blood

6.43% at 5 min and decreased to 0.35% at 4h. A little distribution appeared in brain with slower clearance

the %ID/g were 0.27% at 5 min and 0.11% at 4h. In heart

lung

spleen

muscle

bone

and intestines

there were little distributions. It is concluded that labeling yield of 131I-salidroside was high and the radioiodinated salidroside was stable

but its uptake in neuroblast was little.