PAF-induced kinin B1 receptor in vivo up-regulation:: involvement of distinct kinase pathways

Platelet activating factor (PAF) is an important mediator in several pathophysiological processes. PAF receptor activation can causes a series of cellular and tissue modifications and can lead to the production and/or release of diverse molecules, including cytokines, chemokines and receptors, amongst others, which are capable of amplifying the inflammation. PAF can up-regulate kinin B, receptor expression by various mechanisms. In the present study, we show an additional mechanism by which PAF can lead to an in vivo up-regulation of B, receptors. Our results clearly show that the phosphorylation of both ERK1/2 and JNK MAPKinases is an important step for this event. However, the exact mechanisms (transcriptional and post- transcriptional) by which PAT can trigger kinase phosphorylation and then up-regulate the B, receptor require further investigation.