Role of PKC down-regulation on LPA- and PMA-induced LPA_1–3 receptor phosphorylation.

<p>Cells overexpressing LPA₁ (panel A, black bars), LPA₂ (panel B, blue bars) or LPA₃ (panel C, red bars) receptors were incubated in the absence or presence of 1 μM PMA overnight, washed and subjected to the receptor phosphorylation protocol. Cells were incubated for 15 min in the absence or presence of 1 μM LPA or 1 μM PMA. Plotted are the percentage of baseline (B) phosphorylations as mean ± S. E. M. of 3–4 experiments using different cell preparations. Representative autoradiographs separated by vertical lines are presented on the top of the figures for the different receptor subtypes. p < 0.001 vs. baseline; ** p < 0.05 vs. baseline.