Hypothalamus, pituitary and thyroid function

Question 1

Describe the anatomy of the hypothalamus, the posterior pituitary and the anterior pituitary

Answer 1

The hypothalamus sends neurones from the hypothalamus to form a posterior pituitary, which releases nueropeptides like oxytocin and ADH. The anterior pituitary is very close but not apart of the brain.

Question 2

Describe the process of the transmission of a hormone from the hypothalamus to the anterior pituitary.

Answer 2

The neurones in the hypothalamus send axons to the median eminence. Therre is no BBB there,, so the hormones enter the portal vessels. They then bind to their complementary receptors.

Question 3

State the 5 hormones released from the hypothalamus

Answer 3

TRH (Thyrotropin releasing hormone)
Prolactin
CRF (Corticotrophin releasing factor)
GnRH (Gonadotrophin releasing hormone)
GHRH (Growth hormone releasing hormone)

Question 4

State the 6 hormones released from the anterior pituitary

Answer 4

TSH (Thyroid stimulating hormone)
ACTH (Adrenocorticotrophin Hormone)
LH (Luteinising Hormone)
FSH (Follice Stimulating Hormone)
GH( Growth Hormone )

Question 5

Name 2 inhibitory molecules that affect the release of hormones and state the systems they target

Answer 5

Somatostatin halts GH/TRH

Dopamine halts Prolactin release

Question 6

Starting at the hypothalamus, describe how LH and FSH are released

Answer 6

Hypothalamus - Releases GnRH via median eminence and portal vessels to the anterior pituitary. The anterior pituitary releases LH and FSH via gonadotrophs.

Question 7

Describe the complications that arise in children that lack FSH or LH and suggest how this can be solved.

Answer 7

These children will not be able to undergo puberty and may lose their reproductive function. GnRH, FSH and LH can be used to manipulate reproductive function, as they are even used in IVF.

Question 8

Starting at the hypothalamus, describe how GH is released

Answer 8

Hypothalamus - Releases GHRH via median eminence and portal vessels to the anterior pituitary. The anterior pituitary releases GH via somatrophs.