The Pig-a assay is a useful in vivo mutation detecting test and is easier to perform than the in vivo transgenic mutation assay. This assay is now recognized to be able to detect a number of mutagenic chemicals administered to rats in sub-acute or sub-chronic dose studies. The present investigation was conducted to evaluate the usefulness of peripheral blood Pig-a assays with total red blood cells (RBC Pig-a assay) and with reticulocytes (PIGRET assay) using two genotoxic rodent carcinogens, 1,3-propane sultone (1,3-PS) and 2-acetylaminofluorene (2-AAF). Male rats were orally administered a single dose of each test compound, and both the RBC Pig-a and PIGRET assays were performed using flow cytometry to measure the Pig-a mutant frequency (MF) before and after dosing on Days 8, 15 and 29. In the experiment with 1,3-PS, significant increases in Pig-a MF were observed from Day 15 and Day 8 in the RBC Pig-a and PIGRET assays, respectively. The results of both assays demonstrated that the increases in Pig-a MF were detectable after a single treatment with 1,3-PS. Furthermore, the difference in the kinetics of the increase in Pig-a MF between the RBC Pig-a and PIGRET assays with 1,3-PS suggests that the PIGRET assay has an advantage in detecting the mutant erythrocytes earlier than the RBC Pig-a assay. In contrast, no significant increases were observed in the Pig-a assays using either RBC or reticulocytes with 2-AAF. The negative results in both assays with 2-AAF may indicate the limitation of the single dose method; however, further investigation at higher doses is necessary to determine limitation of the single dose method.

中文翻译：

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使用 1,3-丙烷磺内酯和 2-乙酰氨基芴单剂量给药方案的大鼠 Pig-a/PIGRET 测定的结果。

Pig-a 试验是一种有用的体内突变检测试验，比体内转基因突变试验更容易进行。该测定现在被认为能够检测在亚急性或亚慢性剂量研究中给予大鼠的许多致突变化学品。本研究旨在评估使用两种遗传毒性啮齿动物致癌物 1,3-丙烷磺内酯 (1, 3-PS) 和 2-乙酰氨基芴 (2-AAF)。雄性大鼠口服单一剂量的每种测试化合物，并使用流式细胞术进行 RBC Pig-a 和 PIGRET 测定，以测量第 8、15 和 29 天给药前后的 Pig-a 突变频率 (MF) . 在 1,3-PS 的实验中，在 RBC Pig-a 和 PIGRET 检测中，分别从第 15 天和第 8 天观察到 Pig-a MF 显着增加。两种测定的结果表明，在用 1,3-PS 单次处理后，可以检测到 Pig-a MF 的增加。此外，RBC Pig-a 和使用 1,3-PS 的 PIGRET 测定之间 Pig-a MF 增加的动力学差异表明 PIGRET 测定在检测突变红细胞方面比 RBC Pig-a 更早化验。相比之下，在使用 RBC 或网织红细胞和 2-AAF 的 Pig-a 测定中没有观察到显着增加。2-AAF 的两种检测结果均为阴性可能表明单剂量方法存在局限性；然而，需要对更高剂量进行进一步研究以确定单剂量方法的局限性。