Gomes Maria Luisa, de Mattos Deise Mara M, Freitas Rosimeire S, Diré Glaucio F, Lima Elaine A C, Souza Sonia Maria S, Bernardo-Filho Mario
Universidade do Estado do Rio de Janeiro, Instituto de Biologia, Departamento de Biofisica e Biometria, Av. 28 de Setembro, 87, Rio de Janeiro, RJ, Brazil.
Cell Mol Biol (Noisy-le-grand). 2002 Nov;48(7):757-9.
We have reported that drugs alter the biodistribution of radiopharmaceuticals used in diagnostic imaging in nuclear medicine. Knowledge of such altered biodistribution is important in making diagnostic from scintigraphy. Mitomycin-C is used as component of many chemotherapeutic regimens to treat different tumors. The biological activities of mitomycin-C can be explained by its ability to inhibit deoxyribonucleic acid synthesis. Since patients on chemotherapeutic treatment can be submitted to nuclear medicine procedures, we studied the mitomycin-C effect on the bioavailability of the technetium-99m-labelled sodium pyrophosphate (9mTc-PYP) using an animal model. Mitomycin (0.45 mg) was administered by ocular plexus way Balb/c mice. One hour after the last dose, 99mTc-PYP (7.4 MBq) was administered and after 0.5 hr the animals (n = 15) were rapidly sacrificed. The organs were isolated, the radioactivity counted in a well counter and the percentage of radioactivity (%ATI) calculated. The results have shown that in the treated animals the %ATI has been decreased in spleen, thymus, heart and brain and increased in lung, liver and bone. The effect of this chemotherapeutic drug on the 99mTc-PYP biodistribution was statistically significant (Wilcoxon test, p < 0.05) and it could be explained by the metabolization or therapeutic action of mitomycin-C.
我们曾报道，药物会改变核医学诊断成像中使用的放射性药物的生物分布。了解这种改变的生物分布对于通过闪烁显像进行诊断很重要。丝裂霉素-C被用作许多化疗方案的组成部分，用于治疗不同的肿瘤。丝裂霉素-C的生物活性可以通过其抑制脱氧核糖核酸合成的能力来解释。由于接受化疗的患者可能会接受核医学检查，我们使用动物模型研究了丝裂霉素-C对99m锝标记的焦磷酸钠（99mTc-PYP）生物利用度的影响。通过眼丛途径给Balb/c小鼠注射丝裂霉素（0.45毫克）。在最后一剂后1小时，注射99mTc-PYP（7.4兆贝可），0.5小时后迅速处死动物（n = 15）。分离出器官，在井型计数器中计数放射性，并计算放射性百分比（%ATI）。结果表明，在接受治疗的动物中，脾脏、胸腺、心脏和大脑中的%ATI降低，而肺、肝脏和骨骼中的%ATI升高。这种化疗药物对99mTc-PYP生物分布的影响具有统计学意义（Wilcoxon检验，p < 0.05），这可以用丝裂霉素-C的代谢或治疗作用来解释。
