endocrinology of growth Flashcards
what are the non-endocrine factors that regulate growth?
genetics is a principle factor
nutrition is critical
freedom from disease
what are the important growth-regulating endocrine factors?
hormones of the growth axis
thyroid hormones
glucose-regulating hormones
gonadal steroids
what are the 2 basic requirements for growth?
cell division/replication
protein synthesis
the final height of a human is determined by the growth of ___________
long bones
long bones grow as _____________ cartilage is replaced by bone
epiphyseal plate
cartilage replacement in long bones adds bone to which end of the diaphysis?
both ends
T/F: during the growth of long bones, the bone can make its own IGF-1
true
when do epiphyseal plates ossify?
during puberty
what are the two hypothalamic hormones that regulate GH secretion?
1) GHRH
2) somatostatin (SS)
what hypothalamic hormone decreases GH production? which increases it?
Decrease production- Somatostatin (SS)
increase production- GHRH
pituitary GH has what direct effects on somatic tissue?
1) stimulates protein synthesis
2) anti-insulin effects
Growth hormone (GH) will stimulate secretion of ______ from the liver and other tissues
IGF-1
T/F: feedback regulation of GH secretion is both long-loop and short-loop negative feedback
true
IGF-1 will ________ the secretion of GH & GHRH
decrease
what hormone will be increased when IGF-1 levels rise?
SS (somatostatin)
both GHRH and SS exhibit what patterns of secretion?
contrasting diurnal patterns
GHRH stimulated during early sleep, SS stimulated more during the day