Neurochemical-neuroendocrine systems in the brain controlling macronutrient intake and metabolism.

Appetite, energy balance and body weight gain are modulated by diverse neurochemical and neuroendocrine signals from different organs in the body and diverse regions in the brain. The hypothalamus plays an important integrative function in this process, acting through a variety of systems that involve a close interaction between nutrients, amines, neuropeptides and hormones. These systems underlie normal nutrient intake and metabolism and are thought to be responsible for shifts in feeding behavior across the circadian cycle and fluctuations relating to gender and age in both rats and humans. Moreover, alterations in these normal neurochemical-neuroendocrine systems may be associated with abnormal eating patterns, such as anorexia nervosa, bulimia and obesity. Understanding the systems that control eating behavior might provide a foundation for the treatment and possible prevention of such disorders.