[Role of heart-type fatty acid binding protein in the brain function].

Long-chain polyunsaturated fatty acids (LCPUFAs) are components of membrane phospholipids and they are abundant in the brain. LCPUFAs are supposed to be involved in several brain functions including emotion, learning and memory. However, the mechanisms of effects of LCPUFAs on brain functions at cellular and molecular levels remains unclear. Because LCPUFAs are insoluble in the intracellular compartment, specific transporters are required to deliver LCPUFAs for appropriate intracellular compartments. Fatty acid binding proteins (FABPs) are believed to play crucial roles as their cellular shuttles. Among various FABPs, heart-type fatty acid binding protein (H-FABP) is highly expressed in neurons of the mature brain and involved in arachidonic acid incorporation in the brain. Moreover, the association of H-FABP and dopamine D2L receptor has been documented by our studies. In this context, we here examined behavioral and molecular biological phenotype of H-FABP gene-ablated mice to clarify function of H-FABP in the higher brain functions.