Determination of biodistribution of 99mTc-3PRGD2 in mice bearing the lung carcinoma xenograft byγcounter / 国际药学研究杂志

ABSTRACT

Objective To establish a quantitative analysis method for determining 99mTc-HYNIC-PEG4-E[PEG4-c(RGDfK)]2 (99mTc-3PRGD2,a radioactive tumor agent)byγcounter, and to investigate the distribution of 99mTc-3PRGD2 in mice bearing with lung carcinoma xenograft. Methods The mice were divided into 4 normal groups and one blocking peptide group(control group). The 99mTc-3PRGD2(8μg/kg)was injected to mice bearing with lung carcinoma xenograft through the tail intravenous administration. Tissues of the normal mice were taken at 0.5,1,2 and 4 h. The control group were treated by 3PRGD2 and 99mTc-3PRGD2. The control mice were injected with the 3PRGD2 saline solution(2.5 mg/ml,0.2 ml)at 0.5 h earlier before the injection of 99mTc-3PRGD2. The tu?mor and organ tissues of the control mice were taken at 2 h. The radioactivity was detected by Gamma Counter. Results The radioac?tivity of 99mTc-3PRGD2 detected was high in the tumor and very low in brain. In addition,high radioactivity in kidneys and bladder sug?gested that the drug excreted by renal. Conclusion The results proved that the blocking peptide can competitively inhibit the combi?nation of 99mTc-3PRGD2 and integrinαvβ3 receptors.