Leptin is an adipocyte-derived hormone that promotes weight loss by reducing appetite and by increasing energy expenditure through sympathetic stimulation to thermogenic tissue. Leptin also produces sympathoactivation to kidneys, hind limb, and adrenal glands, suggesting that the obesity-associated increase in sympathetic nerve activity could be due in part to these sympathetic effects of leptin. Leptin produces an array of autonomic and cardiovascular actions. Most human obesity appears to be associated with partial leptin resistance. However, recent studies indicate that leptin resistance may be selective, with preservation of adverse sympathetic effects despite the partial loss of favorable satiety and thermogenic (metabolic) actions of leptin. Understanding of the molecular mechanisms and spectrum of selective leptin resistance may have implications for understanding the role of leptin the cardiovascular complications of obesity...