Neuroendocrine System - 26

Question 1

This structures is known as the “master regulator of homeostasis.”

Answer 1

Hypothalamus

Question 2

What kind of info does the hypothalamus receive?

Answer 2

The hypothalamus receives descending information from the brain, ascending visceral and somatic sensory information, and chemosensory information.

Question 3

What 5 things does the hypothalamus control?

Answer 3

Control of blood flow/volume Regulation of energy metabolism Regulation of temperature Regulation of reproductive function Coordination of responses to stress

Question 4

How does the hypothalamus control blood flow/volume?

Answer 4

It controls adjustments to cardiac output, vascular tone, blood osmolarity, renal clearance and the urge to drink water/take in salt.

Question 5

How does the hypothalamus regulate energy metabolism?

Answer 5

It monitors blood glucose levels and feeding behavior, digestive functions and metabolic rate.

Question 6

How does the hypothalamus regulate temperature?

Answer 6

It alters the amount of thermogenesis and stimulates behaviors such as seeking colder or warmer environments (getting in shade)

Question 7

How is the hypothalamus in control of of reproductive function?

Answer 7

It influences gender identity, sexual orientation, mating behavior and (in females) menstrual cycle, lactation and pregnancy.

Question 8

How does the hypothalamus coordinate responses to stress?

Answer 8

It regulates the amount of stress hormones and controls the balance between sympathetic and parasympathetic activity.

Question 9

What are the three regions of the hypothalamus?

Answer 9

Anterior, tuberal, and posterior regions

Question 10

What is the most inferior part of the anterior region? What does it control?

Answer 10

Suprachiasmatic nucleus : circadian rhythm

Question 11

What does the anterior hypothalamus do?

Answer 11

Integrates different types of sensory info to determine if there is a deviation from physiologic norm. Controls blood pressure/composition, body temp, reproductive activity, many hormone levels, and circadian rhythm

Question 12

What are the important nucleus of the Tuberal hypothalamus?

Answer 12

Dorsomedial/ventromedial nucleus Paraventricular nucleus Arcuate nucleus/periventricular nucleus Supraoptic nucleus

Question 13

What does the Dorsomedial/ventromedial nucleus do?

Answer 13

Projects within the hypothalamus to regulate complex integrative functions (growth, feeding, reproduction)

Question 14

What does the Paraventricular nucleus do?

Answer 14

Controls the posterior and anterior pituitary gland. Contains neurons that innervate both the sympathetic and parasympathetic preganglionic neurons thereby controlling autonomic function.

Question 15

What type of cells are contained within the paraventricular nucleus? What do they do?

Answer 15

Both magnocellular and parvocellular components control the posterior and anterior pituitary gland.

Question 16

What kind of neurons are contained within the periventricular and arcuate nucleus?

Answer 16

Parvocellular neuroendocrine neurons

Question 17

What kind of neurons are contained within the Supraoptic nucleus?

Answer 17

Magnocellular neuroendocrine cells

Question 18

Remember this picture:

Answer 18

Question 19

What are the main regions of the posterior hypothalamus?

Answer 19

the Mammillary body, Posterior hypothalamic region, and tuberomammillary nucleus.

Question 20

What does the posterior hypothalamus do?

Answer 20

Not well understood

Tuberomammillary nucleus composed of histamineric neurons that control arousal and wakefulness

Question 21

Name the structures

Answer 21

Question 22

Name the structures

Answer 22

Question 23

Answer 23

Question 24

Answer 24

Question 25

Answer 25

Question 26

Answer 26

Question 27

Where are Parvocellular endocrine neurons located?

Answer 27

In the paraventricular, periventricular, and arcuate nuclei

Question 28

Where are magnocellular endocrine neurons located?

Answer 28

In the Paraventricular and Supraoptic nuclei

Question 29

Where do the magnocellular endocrine neurons project to? What do they do?

Answer 29

Directly to the posterior pituitary gland They release neuropeptides directly into the bloodstream

Question 30

What are the two kinds of Parvocellular cell types?

Answer 30

Parvocellular Neurons, and parvocellular autonomic neurons

Question 31

What do parvocellular endocrine neurons do?

Answer 31

They project to the “portal vasculture” of the anterior pituitary gland. Release their neuropeptides through the portal blood system, down to the pituitary, that then produce/release their own hormones

Question 32

Parvocellular endocrine neurons control the endocrine system ____________ by secreting regulatory hormones into the \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_, which feeds the anterior pituitary.

Answer 32

Indirectly : local portal circulation

Question 33

Magnocellular endocrine neurons control the endocrine system ___________ by secreting regulatory hormones into \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.

Answer 33

Directly : the general circulation

Question 34

What two neuropeptides are released by magnocellular neurons?

Answer 34

Oxytocin and vasopressin

Question 35

What do the parvocellular endocrine neurons release?

Answer 35

Several releasing and inhibiting hormones

Question 36

What do the parvocellular autonomic neurons release?

Answer 36

Oxytocin and vasopressin

Question 37

Where do the parvocellular endocrine neurons project?

Answer 37

Anterior petuitary

Question 38

Where do the parvocellular autonomic neurons project to?

Answer 38

The preganglionic autonomic neurons (medulla/spinal cord)

Question 39

How are the parvocellular autonomic neurons different from the magnocellular endocrine neurons since they both release oxytocin and vasopressin?

Answer 39

The PAneurons release them into a synapse and they act as a neuropeptides. the magnocellular release them into the bloodstream as a hormone.

Question 40

What does vasopressin do when released by the magnocellular endocrine neurons?

Answer 40

Vasoconstriction, water resorption by the kidneys (^blood pressure)

Question 41

What does oxytocin do when released by magnocellular endocrine neurons?

Answer 41

Uterine contraction and milk ejection

Question 42

What 2 neuropeptides are released from the parvocellular endocrine neurons?

Answer 42

TRH - thyrotropin-releasing hormone, and CRH - corticotropin-releasing hormone

Question 43

What is thyrotropin?

Answer 43

Thyrotropin - TSH - Thyroid stimulating hormone : stimulates release of thyroid hormones from the thyroid gland : enhances metabolism and grown.

Question 44

What is adrenocorticotropin?

Answer 44

ACTH - Stimulates the production of mineralo- and gluco-corticosteroids from the adrenal gland and promotes release of androgenic steroids

Question 45

What does the fact that humans maintain the same body weight for years show?

Answer 45

Feeding behavior is subject to a control mechanism.

Question 46

What types of things can alter the “set point” of a person’s body weight?

Answer 46

Stress, exercise, palatability of food

Question 47

What portion of the brain controls feeding?

Answer 47

The hypothalamus controls part of it.likely several nuclei

Question 48

What hormones regulate feeding?

Answer 48

Ghrelin, Leptin, and POMC

Question 49

What is ghrelin?

Answer 49

A hormone that is secreted by the stomach prior to feeding; signal for hunger

Question 50

What is leptin?

Answer 50

A hormone secreted by adipocytes following feeding; signal for satiety

Question 51

What is POMC? What is one of its neuropeptides?

Answer 51

Pro-opiomelanocortin; secreted by hypothalamic cells in response to ghrelin and leptin : Alpha-MSH

Question 52

What is Alpha-MSH? WHat is its receptor?

Answer 52

A neuropeptides encoded by POMC; regulates satiety via binding to its receptor : MCR4

Question 53

Where is MCR4 found?

Answer 53

Several brainstem nuclei