PECAM1 is phosphorylated

LDL causes a transient increase in p38 MAPK activity in platelets. After an initial phase in which LDL leads to the activation of p38MAPK, LDL leads to tyrosine phosphorylation and thereby activation of PECAM-1, which in turn leads to binding and stimulation of the Ser/Thr phosphatases PP1/PP2A which reduce the activity of p38MAPK by dephosphorylation.

低密度脂蛋白（LDL）可导致血小板中p38 MAPK活性的短暂增加。在低密度脂蛋白引发p38MAPK激活的初始阶段之后，低密度脂蛋白进一步导致酪氨酸磷酸化，从而激活PECAM-1，进而引发Ser/Thr磷脂酶PP1/PP2A的结合与激活，这些酶通过去磷酸化作用降低p38MAPK的活性。