FABP3/H-FABP. Fattyacid binding protein-3 (FABP3; also named Fatty acid binding protein 11,FABP11, H- or M- (heart or muscle) FABP, Mammary derived growth inhibitor, orMDGI) is a member of a large superfamily of lipid binding proteins that areexpressed in a tissue specific manner (1, 9, 10). FABP3 is one of tencytoplasmic FABPs that are 14-15 kDa in size and range from 126-140 aminoacids (aa) in length (1,  2, 3). Although all are highly conserved in theirtertiary structure, there is only modest aa identity between any two members.The FABP family members are subdivided based on organ or tissue type it wasoriginally expressed or identified; liver- (L-FABP), intestine- (I-FABP), heart-(H-FABP), adipocyte- (A-FABP), epidermal- (E-FABP), ileal- (IL-FABP), brain-(B-FABP), myelin- (M-FABP) and testis-FABP (T-FABP) (1). Human H-FABP, the productof the FABP3 gene, is a 132 aa cytosolic protein that shows a flattened beta-barrel structure generated by a series of antiparallel beta ‑strands and twoalpha ‑helices(4, 5, 7). One molecule of FABP3 is capable of binding onelong-chain fatty acid (6, 8, 11).It is suggested that ligands first bind to the outside of the molecule, andthis binding subsequently induces a conformational change in the bindingprotein, resulting in "internalization" of the ligand (7, 11). HumanFABP3 is 86%, 89% and 89% aa identical to mouse, rat and canine FABP3,respectively. It also shows 29% and 32% aa identity to human L-FABP and I‑FABP, respectively.