Hypothalamus V

Question 1

GnRH: location of cells, pituitary hormone, peripheral hormones.

Answer 1

diffuse preoptic

pit: LH, FSH
peripheral: estrogen, progesterone, testosterone (also activin and inhibin)

Question 2

GHRH; somatostatin: location of cells, pituitary hormone, peripheral hormones.

Answer 2

Arcuate and PVN
pituitary: GH (somatotropin)
peripheral:
bone and liver. Liver makes IGF-1

Question 3

CRH: location of cells, pituitary hormone, peripheral hormones.

Answer 3

PVN

pituitary: ACTH
peripheral: adrenal glucocortiocids

Question 4

TRH: location of cells, pituitary hormone, peripheral hormones.

Answer 4

cells in the PVN

pituitary: TSH
perpheral: T3, T4 in the thyroid

Question 5

Dopamine: location of cells, pituitary hormone, peripheral hormones.

Answer 5

arcuate

pit: prolactin
peripheral: mammary glands.

Question 6

What happens with vasopression (where produced, where stored)

Answer 6

made in magnocellular neurons of the supraoptic and paraventricular nucleus (PVN). transported to the POSTERIOR pituitary. Stored in secretory granules until released into the circulation based on stimulation from neurons in hypothalamus circumventrricular organs.

Question 7

Where are thermosensitive neurons?

Answer 7

Preoptic region

Question 8

What are the thermosensitive neurons involved with in addition to thermoregulation?

Answer 8

sleep. increase firing rate at the onset of sleep.

Question 9

How does fever happen?

Answer 9

increased prostaglandin activity in the preoptic nuclei.

Question 10

What is one important function of medial preoptic region?

Answer 10

sexual function. maybe maternal behaviors.

Question 11

What is leptin?

Answer 11

synthesized by adipose tissue and proportional to the amount of adipose tissue. this is sensed by the brain. Should act as a break on food intake when food is not needed.

Question 12

Where are the main receptors for leptin?

Answer 12

arcuate nucleus.

Question 13

How does insulin contribute to weight?

Answer 13

stimulates the synthesis of fat, proteins and glycogen and inhibits their release. receptors in the hypothalamus lead to reduced food intake and weight loss. too much insulin could lead to obesity.

Question 14

What is ghrelin?

Answer 14

hormone secreted by the stomach that opposes leptin. will increase feeding and adiposity. Increase during fasting when leptin drop –> signal to induce hunger.

Question 15

Where are ghrelin receptors found?

Answer 15

arcuate nucleus.

Question 16

What are the functions of anapolic peptides and some examples

Answer 16

NPY, AgRP

increase food intake, decrease energy output, increase adipose tissue/weight.

Question 17

What synthesizes NPY and AgRP?

Answer 17

arcuate nucleus

Question 18

Biochemically, what does AgRP do?

Answer 18

can increase feeding for up to six days

antagonist at the MC3, MC4 receptors in the PVN (these are the ghrelin receptors, so it is antagonizing ghrelin).

Question 19

What do catabolic peptides do? Where synthesized? Eamples?

Answer 19

decrease feeding.

CART and a-MSH made in the arcuate nucleus.

Question 20

Biochemically, what does a-MSH and CART do?

Answer 20

bind to MC3 and MC4 receptors in the PVN, VMH, and VLH (it is an agonist). maybe a new drug target.