Liver Targetability and Pharmacokinetics of $[^3H]$-Methotrexate-Lactosaminated Bovine Serum Albumin Conjugates

$[^3H]$-메토트렉세이트-락토오스아미노화한 소 혈청 알부민 공유결합체의 간표적성 및 체내동태

The organ distribution of $[^3H]$-methotrexate-lactosaminated bovine serum albumin conjugates ($[^3H]$-MTX-LBSA) was investigated to examine their role as a liver-specific anticancer drug. Synthesis of lactosaminated bovine serum albumin(LBSA) with BSA, lactose and sodium cyanoborohydride through reductive amination was followed by its conjugation with methotrexate (MTX) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), thereby synthesizing [$[^3H]$-MTX-LBSA conjugates. Organ distribution and plasma elimination profiles were studied in male Wistar rats after intravenous injection of [$[^3H]$-MTX-LBSA conjugates. The fates of $[^3H]$-MTX and the $[^3H]$-MTX-BSA conjugates´fates were also investigated for comparison. The results showed that the plasma level of $[^3H]$-MTX-LBSA conjugates declined more rapidly than those of $[^3H]$-MTX-BSA and their liver concentration was significantly higher than those of other treatment (p<0.01). In addition, their uptake compared to the amount taken up by the liver (1 : 33.1 at 10 min, 1 : 24.1 at 120 min). All these suggested that MTX-LBSA conjugate is one of the drug delivery system (DDS) that is advanced in concentrating MTX in the liver and minimizing the renal toxicity of MTX.