Biology 118 Study Guide Final

Study guide, block exam 5, boil 118, Fall 2012, Dr. Benjamin Smarr. * Hunger * Neural regulation of * These include hormones and nutrients from the periphery that convey information about energy availability to the brain, and to the hypothalamus in particular. Neurons in distinct hypothalamic nuclei that are targeted by these molecules project to other hypothalamic nuclei as well as to extrahypothalamic sites. The complex process of regulating food intake is now known to involve the brainstem and limbic and striatal areas. This poster provides an overview of some of the molecules and circuits that are involved in the regulation of food intake and energy balance. * Hormonal regulation of * More on these hormones http://hungerhormones.com/hypothalamus.html * Lateral Hypothalamus: This region of the brain is associated with hunger recognition.
Ventromedial Hypothalamus: This nuclear region is involved with the recognition of the feeling of fullness.
Paraventricular Hypothalamus: This nuclear region is involved with the regulation of hunger.
Chemical Hunger: Ghrelin
The hormone ghrelin is produced by the stomach and the hypothalamus. Hormonal levels of ghrelin have been shown to increase before meals and decrease after. Ghrelin was the first discovered hunger hormone. The hypothalamus has receptors for ghrelin, which signals the body of hunger. Ghrelin has also been associated with certain aspects of certain addictive drugs, alcohol, and is associated with food cravings as a reward.
Chemical Hunger: Leptin
The hormone leptin is produced by adipose (fat) tissue, and binds to certain receptors of the hypothalamus. Leptin works oppositely of ghrelin, and signals the body that it is full. Leptin also has specific roles in the regulation of energy expenditure and intake. * Anatomy of * Gut: The gut is at the core of understanding appetite, as the image of a full belly after a meal attests. The