1. Feeding Pathways

2. Hunger vs. Satiety Controlled by communication between the gut and
parasympathetic nervous system
Neuroscience (Bears, Connors, Paradiso)

3. Some Basic Feeding Terminology
Feeding Behavior:
Hyperphagy: increase in food intake (often used to explain pathological eating)
Hypophagy: decrease in food intake
Feeding Physiology:
Orexigenic: release of a drug or hormone that increases food intake
Anorexigenic: release of a drug or hormone that decrease food intake

4. Peripheral Regulation of Food Intake
Leptin (anorexigenic; satiety)
Ghrelin (orexigenic; hunger)

5. Dysregulation of leptin leads to…
The ob/ob mouse: do not have circulating leptin levels, but this does not mean that they are insensitive to leptin
In fact, they are hypersensitized to exogenously administered leptin. WHY?
animal model of Type II diabetes

6. Central Regulation of Food Intake
The BIG THREE hypothalamic
areas regulating food intake are:
Lateral hypothalamus
Ventromedial hypothalamus
Arcuate Nucleus

7. Central Regulation of Hyperphagy
NPY/AgRP-containing enhance feeding behavior

8. Central Regulation of Hypophagy
αMSH/CART-containing inhibit feeding behavior

9. Balance Between Two Pathways
Competitive agonism of MSH receptors and antagonism of MC4 receptors by leptin

10. Central Regulation of Thirst
Communication between neurons in the pituitary (organum vasculosum of lamina terminalis [OVLT] and vasopressin-secreting neurons) and kidneys
Diabetes Insipidus