Inhibition of p85 and PAC1 but not total α_IIbβ₃ expression upon p85 antisense treatment. HEL and primary megakaryocytic cells were treated with p85 sense or antisense oligonucleotides for 3 days, while control cells were left untreated. (A) p85 protein and β-tubulin were sequentially detected on the same filter after SDS-PAGE and Western blotting with specific antibodies. Lanes: 1, untreated HEL cells; 2, HEL cells treated with p85 sense; 3, HEL cells treated with p85 antisense. m.w., molecular weights. The expression of activated and total α_IIbβ₃ was analyzed by FACScan with PAC1 or anti-CD41a MoAb, respectively, in primary megakaryocytic (B) and HEL (C) cells as described in Materials and Methods. Data are expressed as means ± SD of three separate experiments.