TY - JOUR T1 - A Detailed Examination of Pulmonary Uptake of 99mTc-Tin Colloid in Healthy Mature Miniature Pigs JF - In Vivo JO - In Vivo SP - 551 LP - 554 VL - 23 IS - 4 AU - KYUNG MI SHIM AU - SE EUN KIM AU - CHANGJONG MOON AU - SUNG-HO KIM AU - CHUN-SIK BAE AU - HO JAE HAN AU - SEONG SOO KANG Y1 - 2009/07/01 UR - http://iv.iiarjournals.org/content/23/4/551.abstract N2 - 99mTc-Tin colloid is a commonly used colloidal radiopharmaceutical in human medicine for evaluating liver function and morphology. 99mTc-Tin colloid is taken up in the liver by the phagocytic activity of Kupffer cells, the reticuloendothelial cells of the liver. Unlike what occurs in human beings, we demonstrated 99mTc-Tin colloid uptake within the lungs and liver in healthy, mature, miniature pigs. Our observations may be explained by the presence of pulmonary intravascular macrophages (PIMs) closely apposed to the endothelium of the pulmonary capillaries in several animal species, such as the sheep, horse, goat, cat and pig. In the current study, we compared scintigraphic images using 99mTc-Tin colloid in rats with those in mature, miniature pigs, and identified the presence of PIMs, reticuloentothelial cells similar to Kupffer cells, by immunohistochemistry in pigs. Pulmonary uptake of 99mTc-Tin colloid occurred only in pigs, and PIMs in the pulmonary capillaries stained positively for mouse monoclonal MAC387 antibodies to macrophages in lung sections, as well as Kupffer cells in liver sections. Therefore, we conclude that the uptake of intravenously injected 99mTc-Tin colloid within both Kupffer cells and PIMs results in scintigraphic imaging of the lung and liver in miniature pigs. ER -