Lysophosphatidylinositol (LPI) has been shown to induce an increase in pancreatic insulin secretion. This effect is due to increasing intracellular calcium concentration. This effect of LPI is exerted by its binding to and activating which of the following receptors?

Question

Quizplus · Accepted Answer

LPI exerts its effect on pancreatic insulin secretion by binding to and activating GPR55, which leads to an increase in intracellular calcium concentration.  The primary receptor for LPI is GPR55 although additional studies have shown that LPI can also bind and activate GPR119. LPI activation of GPR55 results in increased intracellular calcium concentrations. This effect of LPI is associated with increased insulin release from the pancreas, arterial contraction, and the proliferation and migration of several cell type. In addition, LPI induces calcium flux in hepatic mitochondria. The effects of LPI on intracellular calcium mobilization are blocked by GPR55 antagonists as well as in cells where GPR55 levels have been downregulated demonstrating the specificity of the role of GPR55 in LPI action.

Lysophosphatidylinositol (LPI) Has Been Shown to Induce an Increase in Pancreatic