Obesity is characterized by increased adiposity of visceral and subcutaneous depots as well as other organs, including the vasculature. These fat depots secrete various hormone-like proteins implicated in metabolic homeostasis (e.g., adiponectin, resistin), the central control of appetite (e.g., leptin) and the increased production of cytokines. These molecules act either in a paracrine or endocrine manner, contributing to the metabolic and cardiovascular complications of obesity. Explant cultures of white adipose tissue are an important step in analyzing the secretory mechanisms of adipose tissue by preserving the physiological in vivo cross-talk between the various types of cells.