Fig. 3.
Role of LPAR5 in regulating platelet function. LPA induces human platelet activation and aggregation through LPAR5. One study proposed the potential involvement of LPAR4 and PPARγ in inhibiting platelet aggregation as their expression was elevated in platelets that were nonresponsive to LPA stimulation (Pamuklar et al., 2008). While the involvement of PPARγ in inhibiting platelet function has been demonstrated with other PPARγ ligands, more research is needed to confirm the role of LPAR4 in modulating platelet function. Murine platelets express LPAR4 rather than LPAR5, which could explain in part why LPA does not induce platelet activation and aggregation in mice.