TY - JOUR T1 - Therapeutic Effects of a <sup>186</sup>Re-Complex–Conjugated Bisphosphonate for the Palliation of Metastatic Bone Pain in an Animal Model JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 122 LP - 127 VL - 48 IS - 1 AU - Kazuma Ogawa AU - Takahiro Mukai AU - Daigo Asano AU - Hidekazu Kawashima AU - Seigo Kinuya AU - Kazuhiro Shiba AU - Kazuyuki Hashimoto AU - Hirofumi Mori AU - Hideo Saji Y1 - 2007/01/01 UR - http://jnm.snmjournals.org/content/48/1/122.abstract N2 - Previously, based on the concept of bifunctional radiopharmaceuticals, we developed a highly stable 186Re-mercaptoacetylglycylglycylglycine (MAG3) complex–conjugated bisphosphonate, [[[[(4-hydroxy-4,4-diphosphonobutyl)carbamoylmethyl]carbamoylmethyl]carbamoylmethyl]carbamoylmethanethiolate] oxorhenium(V) (186Re-MAG3-HBP), for the treatment of painful bone metastases. This agent showed a superior biodistribution as a bone-seeking agent in normal mice when compared with 186Re-1-hydroxyethylidene-1,1-diphosphonate (186Re-HEDP). In this study, we evaluated the therapeutic effects of 186Re-MAG3-HBP using an animal model of bone metastasis. Methods: The model was prepared by injecting syngeneic MRMT-1 mammary tumor cells into the left tibia of female Sprague–Dawley rats. 186Re-MAG3-HBP (55.5, 111, or 222 MBq/kg) or 186Re-HEDP (55.5 MBq/kg) was then administered intravenously 21 d later. To evaluate the therapeutic effects and side effects, tumor size and peripheral blood cell counts were determined. Palliation of bone pain was evaluated by a von Frey filament test. Results: In the rats treated with 186Re-HEDP, tumor growth was comparable with that in untreated rats. In contrast, when 186Re-MAG3-HBP was administered, tumor growth was significantly inhibited. Allodynia induced by bone metastasis was attenuated by treatment with 186Re-MAG3-HBP or 186Re-HEDP, but 186Re-MAG3-HBP tended to be more effective. Conclusion: These results indicate that 186Re-MAG3-HBP could be useful as a therapeutic agent for the palliation of metastatic bone pain. ER -