Interrelation between half-life of nuclear medicine and damage of vascular endothelial cell

核醫藥物半衰期與血管內皮細胞損傷之間的相關性

曾文昌(Wen-Chang Tseng) ； 何鎔莉(Jung-Li Ho) ； 王永成(Yung-Cheng Wang) ； 陳偉琪(Wei-Chi Chen)

《輔仁醫學期刊》 17卷4期 (2019/12) Pp. 169-184

https://doi.org/10.3966/181020932019121704002

摘要

Objective: Nuclear medical examination is to use agents labeled on unstable radioactive seeds. Then, these tracer agents are injected into the patient's body or absorbed orally. According to the characteristics of various tracer agents distributed to some specific tested organs, the extremely small amount of gamma rays emitted by these unstable nuclear seeds can be taken by radiological detection instrument for diagnosis. According to the previous literature and clinical studies, the quality of nuclear medicine is a relatively balanced role in the science of nuclear imaging. This research puts forward a hypothesis is: when radioactive tracer injection organisms, after a half-life, two half-life and after 24 hours, vascular endothelial cells in nuclear medicine retention, whether can produce damage effect. Methods: Experiments were conducted via the rat femoral vein injection dye agent Evans blue (EB), which was followed by the injection of the same concentration, a different dose (0.2 mCi, 1 mCi and 5 mCi) of radioisotope (free ^(99m)Tc) and then the EB in the tissue to measure the vascular permeability. Results: The longer the retention time, the vessels present a very slight leakage reaction. In addition, according to the colloid carbon leakage markers and the histomorphological experiments, the experimental results of vascular leakage showed that the experimental group showed a very small amount of colloid carbon leakage, and the red blood cells were only slightly infiltrated. However, the results showed no significant difference with the saline injection (control group). In terms of immunohistochemical staining, the presence of nitrotyrosine can serve as an indicator. The experimental results showed that the longer the residence time of nuclear drugs, the darker the color of nitrotyrosine. Taken together, these results suggest that the longer the exposure to radiation, the more NO is produced, or perhaps the endothelial cells are destroyed and the leakage increases. The conclusion of this study is that the excessive production of NO is involved in the vascular injury and leakage caused by radioactive nucleation seeds in vivo.

關鍵字

half-life ； vascular endothelial damage

並列摘要

目的：核子醫學檢查是利用藥劑標定於不穩定的放射性核種上，然後，把這些示 蹤性藥劑注射到病人體內，或是口服吸收，並依據各種示蹤劑分佈到某些特定受檢器官的特性，再由這些不穩定的核種所放射出的極微量加瑪射線，以放射線偵測儀器取像，從而判別診斷。依照之前的文獻及臨床研究指出，核醫藥物劑量與影像攝取品質在核子醫學影像學的因果關係中，扮演了一個相對平衡的角色。本研究所提出的一個假說是：當放射性示蹤劑注入生物體內，經過一個半衰期、二個半衰期和24小時之後，血管內皮細胞在核醫藥物滯留之下，是否會產生損傷效應。實驗方式：實驗是經由大鼠股靜脈注射染劑Evans blue（EB），接著注射相同濃度、不同劑量（0.2 mCi, 1 mCi and 5 mCi）的放射性同位素（free ^(99m)Tc），然後粹取組織中的EB以測量血管滲透度。結果：隨著滯留時間越長，血管呈現非常微量的滲漏反應，其結果與saline注射（控制組）結果無顯著性差異。另外，依照膠體碳滲漏標記以及組織形態學實驗方面，顯示：實驗組出現膠體碳非常少量的滲漏情形，且紅血球也只有微量外滲。至於在免疫組織化學染色方面，以nitrotyrosine的存在當作指標。實驗結果顯示：核醫藥物滯留時間越長，nitrotyrosine的呈色就越深。結論：暴露於放射線的時間越長，NO的產生就越多，血管內皮細胞被破壞滲漏的情形就會增加。NO的過量產生抑或參與放射性核種所造成的血管傷害及滲漏。

並列關鍵字

半衰期 ； 血管內皮細胞損傷