endocrinology- basic principles :0

Question 1

examples of protein and polypeptide hormones

Answer 1

• growth hormones
• prolactin
• insulin
• oxytocin

these are hormones encoded by genes made up of amino acid chains of various lengths

Question 2

examples of amino acid derived hormones?

Answer 2

• tyrosine
• adrenaline
• tryptophan
• melatonin

much smaller hormones

Question 3

examples of steroid hormones?

Answer 3

• cholesterol
• testosterone
• oestradiol

Question 4

where are steroid hormones usually synthesised?

Answer 4

• adrenal glands

- reproductive organs

Question 5

what are the 4 main groups of hormone receptors?

Answer 5

• G protein coupled receptors
• Receptor Tyrosine Kinase (RTK) Families
• Receptors associated with tyrosine kinase activity
• Steroid hormone receptors

Question 6

what similar features do all G-protein couples receptors share?

Answer 6

all have:

• an extracellular domain
• an intracellular domain
• 7 transmembrane domain

Question 7

what does the extracellular domain in G protein coupled receptors do?

Answer 7

ligand binding

Question 8

what does the intracellular domain in a G couples protein receptor do?

Answer 8

activates intracellular signalling cascade

Question 9

what type of receptor is the insulin receptor?

Answer 9

receptor tyrosine kinase families

Question 10

where are steroid hormones receptors usually found?

Answer 10

-intracellular either in cytoplasm or nucleus

Question 11

what will the ability to accurately measure hormone levels depend on?

Answer 11

-pattern of secretion
-the presence of carrier hormones
-interfering agents
-stability of hormones
-absolute concentration
!!major determinant= rate of secretion!!

Question 12

what would a raised TSH suggest?

Answer 12

hypothyroid

Question 13

what would a suppressed TSH suggest?

Answer 13

hyperthyroid

Question 14

why might it not be reliable to measure TSH levels in unwell patient?

Answer 14

their TSH levels may fall and then rise later on

Question 15

would taking a random cortisol test be a good indication of HPA axis function?

Answer 15

no, cortisol varies so much throughout the day, it would be better to take it at 9am

-need dynamic testing to really tell HPA axis function

Question 16

what is HPA axis?

Answer 16

-its a term used to represent the interaction between the hypothalamus, pituitary gland and adrenal glands and plays an important role in stress response

Question 17

what is the formal diagnostic test for cushings syndrome?

Answer 17

low dose (1mg overnight) dexamethasone suppression test and if there is a failure to suppress then it is cushings