Principles of Endocrinology Flashcards
most diverse hormone subtype?
proteins and peptides
what are prehormones?
large inactive hormones that undergo proteolytic change
name the 4 main hormone receptors
GPCR
receptor tyrosine kinase
steroid hormone receptors
cytokinase receptors (linked to TK activity)
what hormone receptor does insulin use?
tyrosine kinase receptor
what are the main chemicals involved in signalling cascades within GPCR?
cAMP
IP3
what receptors are seen as the main sensors of the internal environment?
GPCR
what happens to TK receptors when insulin binds?
undergo a conformational change
name 2 hormones that perform signalling via TK activity?
prolactin receptor
growth hormone receptor
are steroid hormone reeptors usually intra or extra cellular?
intracellular
where in the cell are steroid receptors typically located?
cytoplasm
nucleus
what is the main aim of hormones that signal via steroid hormone receptors?
to change gene transription
how does the hypothalamus control release of hormones from the anterior pituitary?
via hypothalamic releasing hormones
main determinant of hormone concentration?
rate of secretion
what is the only hormone not to be triggered by hypothalamic secretion?
prolactin
what hormones should be tested regularly?
thyroid steroid GH reproductive and sex hormones prolactin
2 types of negative feedback?
short or long acting loop
what would a normal TSH indicate?
normal thyroid
what would a raised TSH indicate?
hypothyroid
what would a suppressed TSH indicate?
hyperthyroid
when would TSH not be a reliable marker of thyroid status?
if you have pituitary disease eg secondary hypothyroidisim or pituitary cancer
what is your first line hormone test?
TSH levels
what hormone test would you do if the first line test was normal?
T3/4 levels