A mixture of lysophosphatidylinositols isolated from porcine liver with various fatty acyl groups at the sn-1 position and a hydroxy group in the sn-2 position; formed via PLA1 or PLA2 catabolism of phosphatidylinositol; induce exocytotic release of insulin by pancreatic islet cells and intracellular calcium mobilization in a variety of cells; increase ERK1/2, Akt, and p38 phosphorylation via GPR55 activation; accumulate in transformed cell lines