Hypothalamus appetite control

How does the brain control behavioral state

The limbic system

What does the hypothalamus do

• Regulation of hormones

• Fight or flight

• Arousal

• Sleep wake and circadian regulation

• Regulation of blood volume and thirst

• Regulation of appetite

Where is the hypothalamus

Where are the limbic structures

What does the lateral hypothalamus area do

• Feeding

• Drinking

• Srousal

• Fight of flight

• Circadian

What does the dorsomedial hypothalamus do

• Feeding

• Cardiovascular control

What does the ventromedial hypothalamus do

• Feeding

• Drinking

• Activity

What does the arcuate nucleus do

Feeding

What does the paraventricular nucleus do

• Feeding

• Drinking

• Parturition

• Cardiovascular control

What does the superoptic nucleus control

Drinking

What does the superchiasmatic nucleus control

Circadian rhythm

What hormones does the hypothalamus regulate

• Controls the pituitary gland

• TSH, FSH, LH, ACTH

• Vasopressin, oxytocin

What are the two roles of the suprachiasmatic nucelus

• Master circadian clock controlled daily rhythms

• Regulation of melatonin secretion

How does light influence the hypothalamus

Melanospin-containing retial ganglion cells detect light and send signals to the SCN to reset the circadian clock

What hormone is involved in day-night signalling from the hypothalamus pathway

Meletonin released from the pineal gland

What does melatonin do

Acts like a hormone to coordinate day might physiological behaviour

What neurotransmitter regulates the sleep wake signal

Orexin

What determines whether orexin increases or decreases at night

Whether the species is nocturnal or diurnal

What two major sleep states and contained by brain pathways

REM and NREM sleep

What feedback system does the hypothalamus mainly use

Negative feedback

Name two responses to high body temperature

Vasodilation and panting

Name one response due to low body temperature

Shivering

Failure of temperature regulation can lead to what two conditions

Hyperthermia and hypothermia

What hormone regulates plasma osmolarity and water balance

ADH

What is the main goal of appetite regulation

Balance energy intake with energy expenditure

Which hormone suppresses appetite

Leptin

Which hormone stimulates appetite

Ghrelin

What does the lipostat theory propose

Appetite is regulated by body fat via leptin signalling

What happens in animals lacking the leptin receptor

Severe obesity

Which hypothalamic pathway decreases feeding when activated by leptin

POMC → MSH → MC4 receptor

What appetite stimulating pathway does leptin inhibit

NPY pathway

Is the lipostat theory long term or short term appetite regulation

Long term

What does the glucostat theory propose

Hunger is regulated by blood glucose levels

According to glucostat theory what triggers hunger

Low blood glucose

Which neurotransmitter is responsible for reward related feeding

Dopamine

Dopamine neurones involved in feeding reward originate from where

Ventral tegmental area

What happens to dopamine receptors with prolonged dopamine stimulation

Down regulation

What drug used for weight loss activates GLP-1 receptors and stimulates POMC neurons

Semaglutide