Growth Hormone Flashcards
(21 cards)
What are examples of non-endocrine factors that may influence growth and development?
- malnutrition
- malabsorption
- chronic hypoxia due to congenital heart failure
- chronic renal disease
- psychological and social deprivation
- ethnic and genetic factors
What are examples of endocrine factors involved in growth process?
- hyper- or hpothyroidism
- precocious or delayed puberty
- prolonged steroid therapy
- hypoparathyroidism
What stimulates the somatotrophe cells of the anterior pituitary to secrete Growth Hormone (GH)?
Growth hormone releasing hormone (GH-RH) and somatostatin
Where is the main target tissue for GH? What happens there?
Liver - stimulates the production and release of somatomedins (mediate most effects of GH)
Is most of the GH transported bound or unbound to growth hormone binding protein (GHBP)?
Bound - only 30% unbound GH is biologically active
What is the main psychological effect of GH?
The promotion of linear growth that occurs during adolescence
GH effect produces an increase in what 2 things?
protein synthesis and extracellular collagen deposition
GH stimulates the availability of what?
nutrients and other elements required for growth (amino acid uptake, lipolysis, fatty acid uptake, etc.)
Fetal growth (embryonic somatomedin) is different from growth at different stages of life. Why?
It is independent of GH
What is GH secretion stimulated by?
Estrogen
Dwarfism is commonly resulted from deficiency of what? Common to have these diseases as well…
GH
Grave’s Disease, Addison’s, and diabetes
The main source of GH production is by what?
using recombinant DNA techniques
GH therapy is helpful in what cases?
AIDS and anterior pituitary damage
What is the most common cause of hypersecretion of GH?
secretory tumor of the anterior pituitary
What does hypersecretion before puberty lead to?
gigantism
What is acromegaly? Characterized by?
Excess GH secretion occurring after epiphyseal closure
Growth of bones other than long bones (i.e. jutting jaw, prominent forehead, and enlarged hands and feet)
Continued growth of internal organs such as spleen, liver, and heart also
What happens in hypERthyroidism?
increased metabolic rate results in utilization of skeletal proteins leading to retardation
What happens in HypOthyroidism?
Failure to undergo spurt of growth occurring before puberty results in retardation
Treatment for HypOthyroidism?
Administration of TH - allows patient to achieve normal height and sexual maturation
What is the difference between thyroid deficient dwarfism and GH deficient dwarfism?
Thyroid - characterized by retention of juvenile proportions (short limb length and immature face)
GH - allows normal maturation (elongation of limbs)
Normal growth may be dependent on what?
Normal secretion of insulin
