Description_x000D_ General description_x000D_ The gene LEP (leptin) is mapped to human chromosome 7q31. It is a 16kDa peptide. Leptin is released in the circulation and goes to the CNS (central nervous system). In CNS, it works by associating with leptin receptor._x000D_ Application_x000D_ Leptin human has been used:_x000D_ • to study the effect of leptin on ACAT1 (acyl-coenzyme A:cholesterol acyltransferase 1) expression and cholesterol efflux from primary cultured human macrophages_x000D_ • to study the effect of leptin on expression of IGFBP2 (insulin growth factor binding protein 2) in skeletal muscle_x000D_ • to study the effect of leptin on HLA-G (human leukocyte antigen G) expression in placental trophoblasts_x000D_ • to study the effect of leptin on in vitro maturation, fertilization and development of horse oocytes after ICSI (intracytoplasmic sperm injection)_x000D_ Biochem/physiol Actions_x000D_ Leptin is a hormone produced primarily in adipocytes, although leptin mRNA has also been identified in placenta and fetal tissues, gastric tissue and liver. Its primary site of action appears to be on neurons in the hypothalamus that are involved in regulating energy balance, appetite, and body weight. Leptin increases the production of nitric oxide in endothelial cells and stimulates angiogenesis in vitro and in vivo._x000D_ Human and mouse leptin share ~84% sequence identity._x000D_ Leptin is believed to play a role in normal pregnancy development._x000D_ Mutations in LEP (leptin) are linked with type-2 diabetes. Presence of high levels of leptin in plasma is related to adiposity._x000D_ Physical form_x000D_ Lyophilized from a 0.2 μm filtered solution with 0.0045 mM NaHCO3_x000D_ Analysis Note_x000D_ The biological activity is measured by its ability to induce proliferation of leptin-dependent human OB-R transfected murine BAF3 cells.