Leptin is a single-chain 16 kDa protein, the product of the ob (obese) gene. Leptin is produced mainly in the adipose tissue and the primary effect of leptin is mediated by leptin receptors expressed mainly in the hypothalamus. Leptin plays an important role in appetite control, fat metabolism and body weight regulation. Leptin was the first adipocytokine discovered. We are proud that BioVendor ELISA kit was the first commercial enzyme immunoassay for the first adipokine. Currently we offer immunoassays to measure human, mouse and rat samples.