LeFevre M E, Hancock D C, Joel D D
J Toxicol Environ Health. 1980 Jul;6(4):691-704. doi: 10.1080/15287398009529888.
Intestinal barrier function in mice was assessed after acute or chronic oral administration of 15.8- and 5.7-micron synthetic spherical particles. The results failed to confirm previous reports that ingested particles rapidly appear in blood. Furthermore, 15.8-micron particles did not accumulate in intestinal Peyer's patches, mesenteric lymph nodes, or other organs of the reticuloendothelial system, even after the maximum dosage of 8 X 10(6) particles per day for 60 d. However, the 5.7-micron particles were demonstrated in Peyer's patches, mesenteric lymph nodes, and lungs after the maximum dosage of 4.5 X 10(8) particles per day for 60 d. At 77 d after the termination of ingestion, 5.7-micron particles were still present in these tissues. The 5.7-micron particles were not found in spleen; retention in liver was equivocal. The site of uptake of particles capable of penetrating the intestinal mucosa appears to be the Peyer's patches. It is suggested that most absorbed particles are sequestered in Peyer's patch macrophages. Particles that escape sequestration are transported by lymph rather than by portal blood. The findings indicate that hazards associated with intestinal uptake of large (> 5 micron) particulates exist, but that the frequency of such penetration is still unclear.
在对小鼠急性或慢性口服15.8微米和5.7微米的合成球形颗粒后，评估其肠道屏障功能。结果未能证实先前关于摄入颗粒会迅速出现在血液中的报道。此外，即使在每天最大剂量为8×10⁶个颗粒、持续60天的情况下，15.8微米的颗粒也不会在肠道派伊尔结、肠系膜淋巴结或网状内皮系统的其他器官中积聚。然而，在每天最大剂量为4.5×10⁸个颗粒、持续60天的情况下，5.7微米的颗粒在派伊尔结、肠系膜淋巴结和肺中被检测到。在停止摄入后77天，5.7微米的颗粒仍存在于这些组织中。在脾脏中未发现5.7微米的颗粒；在肝脏中的滞留情况不明确。能够穿透肠黏膜的颗粒的摄取部位似乎是派伊尔结。据推测，大多数被吸收的颗粒被隔离在派伊尔结巨噬细胞中。未被隔离的颗粒通过淋巴而不是门静脉血运输。研究结果表明，存在与肠道摄取大颗粒（>5微米）相关的危害，但这种穿透的频率仍不清楚。
