Evaluation of the cytogenetic effects of I-131 preceded by recombinant human thyrotropin (rhTSH) in peripheral lymphocytes of Wistar rats

Autor(es)

da Silva, Marcia Augusta ^[1] ; Calil Cury Guimaraes, Maria Ines ^[2] ; Yoriyaz, Helio ^[3] ; Carvalho Pinto Ribela, Maria Teresa ^[1] ; Buchpiguel, Carlos Alberto ^[2] ; Bartolini, Paolo ^[1] ; Okazaki, Kayo ^[1]

Afiliação do(s) autor(es)

^[1] IPEN CNEN SP, Ctr Biotechnol, BR-05508900 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Fac Med, Ctr Med Nucl, Sao Paulo - Brazil

^[3] IPEN CNEN SP, Ctr Engn Nucl, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: RADIATION AND ENVIRONMENTAL BIOPHYSICS; v. 47, n. 4, p. 453-461, NOV 2008.
• Citações Web of Science: 4

Resumo

The present study was carried out to investigate the cytogenetic effects of therapeutic exposure to radioiodine preceded by rhTSH in an animal model. Three groups of Wistar rats (n = 6) were used: one group was treated only with I-131 (11.1 MBq/animal); the other two groups received rhTSH (1.2 mu g/rat of either Thyrogen or rhTSH-IPEN, respectively) 24 h before administration of radioiodine. The percentage of lymphocytes with chromosome aberrations and the average number of aberrations and of dicentrics per cell were determined on blood samples collected 24 h, 7 and 30 days after administration of I-131. The data show that the treatment with radioiodine alone or associated with rhTSH resulted in a greater quantity of chromosome alterations in relation to basal values after 24 h, with a gradual decline after 7 and 30 days of treatment. An increase in chromosome alterations was also seen after rhTSH treatment alone. Neither of the treatments, i.e., with I-131 alone or associated with hormone, resulted in an aneugenic effect or influenced the kinetics of cellular proliferation in rat blood lymphocytes. There was no significant difference between the cytogenetic effects of Thyrogen and rhTSH-IPEN treatment. These data suggest that the treatment with radioiodine, associated or not with rhTSH, affects to a limited extent a relatively small number of cells although the occurrence of late stochastic effects could not be discarded. (AU)

• Processo FAPESP: 02/09872-6 - Avaliacao do efeito citogenetico do i-131 precedido por estimulo com hormonio tireotrofico humano recombinante, em modelo animal.
• Beneficiário: Paolo Bartolini
• Modalidade de apoio: Auxílio à Pesquisa - Regular