24.2 Phys: Pituitary function and failure

Question 1

What is the difference between the anterior/posterior pituitary gland?

Answer 1

Anterior:
Vascular (Hypothalamic-hypophyseal portal system)
‘Real endocrine gland’
Epithelial origin

Posterior:
Neural
Brain out-pouching

Question 2

What are 2 examples of hormones from the posterior pituitary?

Answer 2

Vasopressin/ADH

Oxytocin

Question 3

What occurs in Kallmann syndrome? Why?

Answer 3

Hypogonadism/anosmia

Due to failure of GnRH neurons to migrate (via olfactory pathway)

Question 4

What are 3 effects of growth hormone?

Answer 4

Metabolic (increase blood fatty acid, glucose)
Tissue/skeleton (increase PRO synthesis)
Increase IGFs from liver

Question 5

What are somatomedins?

Answer 5

IGF-I, IGF-II

Question 6

What plays a permissive role for tissue and bone growth?

Answer 6

Thyroid hormone

Question 7

What closes the epiphyseal plates of long bones?

Answer 7

Oestrogen

Question 8

What occurs in growth hormone deficiency?

child, adult and if GH R’s are unresponsive

Answer 8

Child, no GH: Dwarfism
Adult, no GH: few effects
GH R’ unresponsive: Laron dwarfism

Question 9

What are some GH independent causes of short stature? (3)

Answer 9

Cretinism (hypothyroidism as a child)
XO chromosomes
Achondroplasia

Question 10

What is acromegaly?

Answer 10

Overproduction of GH as an adult resulting in bone/soft tissue deformity, increased viscera size and content