Ant/Pos Pit

Question 1

What are the water soluble hormones of the pituitary?

Answer 1

Oxytocin, Catecholamines, And protein hormones such as HGH.

Question 2

Where can the hypothalamus be found?

Answer 2

Within the third ventricle in the diencephalon of the brain.

Question 3

What nucleus within the hypothalamus provides rhymic control?

Answer 3

The superchiasmatic nucleus receiving signalling from the retinohypothalmic fibers.

Question 4

Which hormones share the same alpha units?

Answer 4

TSH, LH, and FSH.

Question 5

How is ACTH released from the pituitary?

Answer 5

CRH from the hypothalamus.

POMC is created and split into ACTH and B-lipotropin with a small ammount of B-endorphin (And melanin Secreting Hormone).

Leads to the secretion of adrenocortical hormones (cortisol, androgens, and aldosterone.)

Question 6

TRH stimulates the release of what hormone?

Answer 6

TRH causes TSH to be released from the anterior pituitary along with prolactin.

Question 7

Growth hormone is released by what factor and what else is released with it?

Answer 7

Growth hormone is released in response to GHRH and is released along with somatostatin that inhibits it.

Ghrelin from the GI can also induce GH release.

Question 8

What hormone restricts prolactin release?

Answer 8

Prolactin following TRH stimulation is inhibited by the hormone dopamine, also known as Prolactin inhibiting hormone.

Question 9

What can cause excessive prolactin release and what effect would it have?

Answer 9

Excessive prolactin release can occur in cases of pituitary stalk tumors. Excess prolactin may lead to infertility.

Question 10

How are hormones released by the posterior pituitary?

Answer 10

The hypothalamus talks to the post. pit. through use of the hypothalamohypophysial tract composed of axpns.

The posterior pit will then release hormones in response to depolarization. The preprohormones are then created in the magnocellular neurons located in either the supraoptic or paraventricular nuclei of the hypothalamus..

Question 11

What nuclei does arginine vasopressin, also known as ADH come from?

Answer 11

This guy is made in the supraoptic nuclei.

Question 12

Describe neurogenic diabetes insipidus.

Answer 12

This is the case in which AVP (ADH) cannot be released this the kidneys are unable to concentrate urine.

Question 13

Describe nephrogenic diabetes.

Answer 13

The kidneys do not have receptors for vasopressin (ADH) on the collecting ducts and thus are unable to concentrate urine.

Question 14

Which nucleus is Oxytocin most likely created in?

Answer 14

Secreted mostly in the Paraventricular nuclei in response to breast feeding and birth.

Question 15

What is psychogenic polydypsia?

Answer 15

This is due to excess water intake causing dilute urine and will return to normal following a reduction in water intake.

Question 16

Which hormone is released following a milk let down response?

Answer 16

Oxytocin from the paraventricular nuclei.

Question 17

When is innapropriate antidiuretic hormone release most commonly seen?

Answer 17

This is most commonly seen in brain tumors.

Question 18

What does Growth hormone cause systemically?

Answer 18

Increased protein stimulus
release of fatty acids
decreased glucose use (insulin resistance)
Increased glucose synthesis by liver
Increased insulin secretion

Question 19

Where are insulin-like growth factors produced and what do they do?

Answer 19

Also known as somatomedins and mostly formed by the liver in response to GH (Tropic effect) but can be formed systemically.

Somatomedin C (IGF-1) prolongs the halflife of growth hormone up to 20 hours!

Question 20

What does the term panhypopituitarism mean?

Answer 20

This is a congenital disorder aquired from a pituitary tumor destroying the pituitary gland leading to abnormally low amounts of growth hormone secretion.
Surgery or other accidents can cause this as well.

Question 21

When is Gigantism and Acromegally seen?

Answer 21

These are both caused by excess growth hormone. Gigantism is seen during puberty when the bone growth plates are still not closed.

Acromegally is the thickening of bone seen after the bone plates have closed.

Question 22

What is a tropic hormone?

Answer 22

These are hormones that target a different organ than the one they were created from.

Question 23

Ghrelin acts as a Growth hormone analogue. In this respect it is called a “ “?

Answer 23

Secretagogue.

Question 24

What are the regulators on GH?

Answer 24

GHRH from the pituitary causes GH to be released but also acts as negative feedback on itself.

Somatostatin is secreted in response to growth hormone and inhibits the release of GH.

Somatomedins (ILG-1) are released from target cells which also shut down GH production.