The aim of this work is to determine the effect of chronic immobilization stress on kinetics and dosimetry of 67Ga in a mouse model. A control group (CG) and a stress group (SG), each with 15 mice, were included in the study, and the latter group was subjected to a chronic immobilization stress model 2 h daily for 14 consecutive days. At day 13, 67Ga-citrate was administered intraperitoneally (11.24 ± 0.44 MBq) to each mouse. Then, sets of three mice were obtained sequentially at 24, 36, 48, 60 and 72 h, in which the radionuclide activity was measured with an activity counter. The 67Ga biokinetic data showed a fast blood clearance in the SG, with a mean residence time of 0.06 h. The calculated mean radiation absorbed doses were: liver (2.45 × 10-03 Gy), heart (3.17 × 10-04 Gy) and kidney (1.88 × 10-04 Gy) in the SG. The results show that stress reduced weight gain by approximately 13% and also increased adrenal gland weight by 26%. On the other hand, chronic stress accelerates 67Ga clearance after 24 h compared to normal conditions. It is concluded that murine organisms under chronic immobilization stress have higher gallium-67 clearance rates, decreasing the cumulated activity and absorbed dose in all organs.

中文翻译：

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慢性固定应激对小鼠模型67Ga的生物动力学和剂量学的影响。

这项工作的目的是确定长期固定压力对小鼠模型中67Ga动力学和剂量学的影响。对照组（CG）和应激组（SG）各有15只小鼠，研究中，后者每天2h接受慢性固定应激模型，连续14天。在第13天，向每只小鼠腹膜内给予67Ga柠檬酸盐（11.24±0.44MBq）。然后，在24、36、48、60和72小时顺序获得三只小鼠的组，其中用活性计数器测量放射性核素的活性。67Ga的生物动力学数据显示，SG中血液快速清除，平均停留时间为0.06 h。计算得出的平均辐射吸收剂量为：SG中的肝脏（2.45×10-03 Gy），心脏（3.17×10-04 Gy）和肾脏（1.88×10-04 Gy）。结果表明，压力使体重增加减少了约13％，肾上腺重量也增加了26％。另一方面，与正常情况相比，慢性应激会在24小时后加速67Ga的清除。结论是，慢性固定应激条件下的鼠类生物具有较高的镓67清除率，降低了所有器官的累积活性和吸收剂量。