Adenosine kinase inhibitor (iodotubercidin) reversed the AICAR induced inhibition of 3T3L1 adipocyte differentiation. The differentiating 3T3-L1 cells were treated with AICAR (0.5 mM) at various differentiating stages (on 0 day, 3rd and 6th day) in the presence or absence of iodotubercidin (0.1 μM). Intracellular lipids were stained with Oil Red O (a). To estimate extent of adipose conversion, 0.2 ml of isopropanol was added to a 12 well plate after 9 days of treatment when AICAR/iodotubercidin was added at 0 day. The extracted dye was immediately removed by gentle pipetting and its optical density was monitored spectrophotometrically at 510 nm (b). Values are mean ± S.D. of three determinations. $ p < 0.001 as compared with untreated cells. *** p < 0.001 as compared with differentiated cells. NS not significant; % p < 0.001 as compared with differentiated cells and AICAR treated cells, respectively. 3T3-L1 cells were treated with AICAR/iodotubercidin (0.5 mM/0.1 μM) during the differentiation induction phase (from day 0 to day2) followed by [3H] thymidine uptake to examine cell proliferation (c). Values are mean ± S.D. of three values. *** p < 0.001; NS not significant as compared with untreated cells. * p < 0.05, *** p < 0.001 as compared to AICAR treated cells (0.5 and 1.0 mM), respectively. 3T3-L1 cells were differentiated in the presence or absence of AICAR/iodotubercidin (0.5 mM/0.1 μM) for 9 days. The protein expression of SREBP1, PPARγ and β actin were examined by immunoblot analysis as described previously (d).