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.Human and mouse leptin share ~84% sequence identity.
