Tohoku J. Exp. Med., 2005, 206(4)

Genotoxicity of Thallium-201 in Patients with Angina Pectoris Undergoing Myocardial Perfusion Study

MUSTAFA YILDIRIM, MEVLIT IKBAL,¹ TULAY TOS,¹ BEDRI SEVEN, IBRAHIM PIRIM¹ and ERHAN VAROGLU

Departments of Nuclear Medicine and, ¹Medical Genetics, Ataturk University, Medical Faculty, Erzurum, Turkey

Thallium-201 (²⁰¹Tl) has been widely used as a nuclear reagent for myocardial blood flow imaging. The purpose of this study was to investigate genotoxic effects of ²⁰¹Tl in patients with angina pectoris (n = 21), who had undergone myocardial perfusion imaging. Lymphocytes were isolated from each patient before, and 3, 30 and 90 days after ²⁰¹Tl administration (111 MBq, 3 mCi) and were analyzed for chromosomal aberrations, sister chromatid exchanges, mitotic index and replicative index. There were significant increases in chromosomal aberrations and sister chromatid exchanges 3 days after ²⁰¹Tl administration (p < 0.001), although no difference was noted in these values after 30 and 90 days (p > 0.05). Moreover, decreased mitotic index and replicative index were noted after 3 days of ²⁰¹Tl administration (p < 0.001). These results suggest that the administration of ²⁰¹Tl for myocardial blood flow imaging may induce genetic damage.

keywords —— myocardial perfusion; thallium-201; sister chromatid exchange; chromosomal aberration; mitotic index; replicative index

© 2005 Tohoku University Medical Press

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Correspondence: Mustafa Yildirim, Ataturk University, Medical Faculty, Department of Nuclear Medicine, 25240 Erzurum, Turkey.

e-mail: musyil@atauni.edu.tr, yildirimumran@hotmail.com