Question

Mechanism of Hypothalamus Regulate Food Intake

Answer 1

There are five important sites in hypothalamus which regulate food intake. Their names and their mechanisms in regulating the food intake are described below:

1. The arcuate nucleus

The base of hypothalamus are rich in this type of cells. They secrete orexigenic neurotransmitters such as neuropeptide Y, opioids, dynorphins, beta-endorphins etc. These increase the appetite and favors food intake.

2. Ventromedial nucleus and lateral hypothalamus

These sites are characterised by the presence of satiety centre. They secrete a anorexigenic transmitters such as leptins and corticotropin releasing hormone. Any damage to this site will lead to increase intake of food and abnormal gain in body weight.

3. Dorsomedial nucleus

This sites has the receptors for orexigenic transmitters. Hence, in presence of these transmitters, they increase the rate of food intake.

4. Paraventricular nucleus and perifornical hypothalamus

Similar to dorsomedial nucleus, these regions regulate the food intake. In presence or anorexigenic transmitters, they reduce the food intake.

5. Suprachiasmatic nucleus

This site of hypothalamus mainly regulates the light-dark cycle also called the circadian rythms. The appetite in humans is dependent on this region. We consume food during the active part of the day and thus these regions in hypothalamus significantly affects the food intake.