[Noninvasive detection of experimental vulnerable atherosclerotic plaques with 99Tc m labeled C2A domain of synaptotagmin I].
OBJECTIVE
(99)Tc(m) labeled C2A domain of synaptotagmin I ((99)Tc(m)-Syt I-C2A) is used for noninvasive detection of vulnerable atherosclerotic plaque.


METHODS
Recombinant C2A domain of synaptotagmin I, overexpressed in E. Coli, was thiolated with 2-iminothiolane (2-IT) and labeled with (99)Tc(m). Atherosclerotic plaques were produced in 5 rabbits by deendothelialization of the abdominal aorta and the rabbits were fed with cholesterol diet for 3 months. Three rabbits not manipulated served as normal controls. All animals were injected with (99)Tc(m)-Syt I-C2A and underwent in vivo imaging thereafter. Aortas were then explanted for ex vivo imaging and histological characterization.


RESULTS
In deendothelialized animals, intense radio-uptake in abdominal aorta, showed by gamma camera at 2 h after injection, was visualized and T/B was 3.25 +/- 0.51 by ROI measurement, quantitative uptake ratio of abdominal aortas with atherosclerotic lesions to thoracic aortas was 8.39 +/- 1.74 in ex vivo imaging. The mean uptake in specimens of abdominal aortas with lesions was 12.6-fold higher than in control abdominal aortas, and 10.2-fold higher than in thoracic aortas of deendothelialized animals by gamma-counter.


CONCLUSIONS
(99)Tc(m)-Syt I-C2A has a high affinity for vulnerable atherosclerotic plaque and is a suitable a gent for the noninvasive detection of vulnerable atherosclerotic plaque.
Fang
Wei
W
Department of Nuclear Medicine, Cardiovascular Institute and Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
Ji
Shun-dong
SD
Wang
Feng
F
Yang
Min-fu
MF
Lü
Bin
B
Liu
Lei
L
Wang
Zi-zheng
ZZ
He
Zuo-xiang
ZX
D000818:Animals; D050197:Atherosclerosis / Q000000981:diagnostic imaging* / Q000473:pathology; D004195:Disease Models, Animal; D007140:Immunoglobulin Fab Fragments; D007553:Isotope Labeling; D008297:Male; D011817:Rabbits; D011877:Radionuclide Imaging; D050863:Synaptotagmin I / Q000276:immunology; D013667:Technetium
D007140:Immunoglobulin Fab Fragments; D050863:Synaptotagmin I; D013667:Technetium