Evaluation of Concanavalin A-induced Acute Liver Injury in Rats using an Empirical Mathematical Model and Dynamic Contrast-enhanced MR Imaging with Gd-EOB-DTPA

Abstract

We evaluated concanavalin A (Con A)-induced acute hepatic injury in rats using an empirical mathematical model (EMM) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA). We allocated 18 rats into 3 groups of six each and intravenously injected them with either 10 mg/kg body weight (BW) of Con A (Con A [10] group), 20 mg/kg BW of Con A (Con A [20] group), or a single dose of of saline (4 mL/kg BW, normal control group). We performed the DCE-MRI studies using Gd-EOB-DTPA (0.025 mmol Gd/kg; 0.1 mL/kg BW) as the contrast agent 24 hours after injection of Con A or saline. We then sampled blood, measured serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and calculated the rate of contrast uptake (α), rate of contrast washout (β), area under the curve (AUC), time to maximum relative enhancement (RE) (T(max)), and elimination half-life of RE (T(1/2)) from the time-signal intensity curves using the EMM. β values were significantly smaller in the Con A (10) and Con A (20) groups than the control group, but α did not differ significantly among the 3 groups. The AUC value was significantly greater in the Con A (10) group than controls, and the T(max) and T(1/2) values were significantly greater in the Con A (20) group than controls. The β, T(max), and T(1/2) values correlated significantly with AST and ALT. In conclusion, the EMM is useful for evaluating Con A-induced acute hepatic injury using DCE-MRI with Gd-EOB-DTPA.