4 - Endocrine control of growth and disorders of growth Flashcards
what are the 4 factors that control growth
genetics, nutrition, hormones
what are teh main hormones that effect frowth
gh
igf 1
thyroid horome
sex teroids
insulin
what is the antatgoin gorwht hornmone
cotrisol
when do sex steriods mainy start
puberty
what are the 2 periods of rapid growth in humans
infancy - first 8 - 10 months of life
puberty
why is there rapid growth in infacny
, this is largely controlled by nutritional intake
due to growth hormen
why is there a spike in growth in puberty
androgens and oestrogen, this produces spikes in gh and igf - 1 hormone
effect of sex hormoens on long bone
terminate growtgh in epiphyes of long bone by sex hormone
gh, igf- 1 also cause long bone elongation
when do thyroid hormes mainly effect gorwth
early years,
when does growth horme effect growth
constantly throughout
when do androgens and eostrogen effect gorwoth
mostly in later years
what are teh hormes for intrautrien growth
inulin, thryoid horme, igf 2
what is congential hypothyrodis
where babeis ar born a nroal size but can’t produ theirown thryoid hormes
wht does a child lok like with low th
metal retardation
infnatile propaiton
effect of nrmal gh and low th
adult prpption
dwarthism
normal distriioinof mass
short staure
name of gh
somatotropin
what cells is growth hormone relased from
somatostatin cells
what hormes control gh
growth hormone inhibiton hormone
growth hormone releasing horone
what other horone does gh need
insulin and thryoid horme in a permissve fashion
what kind of receptor does gh work on
tyrosine kinase
what are teh action of gh
regualtion of metabolim
growth of long bones with igf 1
increases glucogeneis by liver
redues the abiltiy of insulin to stimalre glucose by mcuel and adipose tisseus
maeks adipoces more censeitee to lipolyic stimuli
increase amino acid uptake and preoin syntehsi in almost all cells
what other homees is igf - 1 like
insulin as it cuaess glucose uptake in to mucel and bone
where if igf 1 from
liver in respone to gh relases
where is igf 2 found
feotus and neonate
what type of hromeon are gh and igf
peptide
how do gh and igf travel in blood
bound to a carrier prtien
what percent of gh is bound
50% to provide a respovier of gh preventing over exertion in urine and prolonging half life
how does ig effect gorwth hormeon
inhibeis ghrn and stimuates ghih
main tissue benifited by gh
bone and brain
when is gh maily relaed in the day
firts 2 hours of sleep , during deep sleep
very little relase in waking hours
how does igf 1 change during hours
very little due to having a 20hr half life
what increase ghrh
decrea in energy supply in cells inlcing cold weather, exercies,
increased amounts of amin acids in plasma, proatin proein sytemh by liver and mucles
physical stress and illenss
delta sleep
oestral and tesotargle - this also prevent igf negative feedbac
what are teh stimuli for ghih
glucose
ffa
ageing
cortisol
what are conditions of hypersection of gh hormes
gigantism
acromegaly
what is gigantism
xs gh due to pituatroy tumuor befor epipheal plates of long bones close
what is acromegaly
xs gh due to pitalary turmou after the epipseal plates close
what are teh signs of acromegaly
bigger feet and hands, and faicl features
what rae caues of hypo section
deffecty in ghrm - hypothalmic origin
defiecy in gh - pituatary origin
genetic mutations - depress downsrea realse of ig 1 and periap tissues cannot respon to teh growth siganl
preconcious puberty sex gnrh stimalus puberty by promating sex hormone relase
hypothryoid dwarfism -
feastues of hypothyroid dwarfism
retain infalie feaue with stund growth
effect of gestation diabes on babes
cause them to be large as it cuase them to anabos by feoal insulin
