Growth Hormone - created from Mind Map

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site of origin

release of GH

actions on the organs level

pathologies and their treatment

Pituitary gland

anatomy

anterior lobe

posterior lobe

infundiblum

paras anterior

paras intermediate

paras distalis

acidophils

basophils

chromophopes

somatotropes

lactotropes

secrete GH

secrete prolactin

gonadotrophes

cotricotrophes

thyrotropes

FSH and LH

ACTH

TSH

colloid filled cysts

secrete MSH

portal venules system

at medial eminence

medial emenince

infundibulum

paras nervosa

connection with the hypothalamus

physiology of hormone release

hypothalamic-hypophyseal tract

hypophyseal portal system

1-hypothalamic nucleus secrete hormones

supraoptic--oxytocin

paraventricular -- ADH

2-released into the axons

3-stored in paras nervosa to be released when needed

1-neuroendocrine cells in the hypothalamus secrete hormones

factors that regulate GH secretion

releasing hormones

inhibiting hormones

2-released into the axons

3-at he medial eminence, they get released into the portal venules to be carried to the anterior pituitary to stimulate or inhibit its hormonal releases

pattern of release: pulsatile

metabolic actions

growth

actions in the cell-- 3 signal transduction pathways

CHO

LIPID

PROTEIN

hyperglycemic effect

muscles+adipocytes

liver-++ gluconeogenesis

-- glucose utilization

increase lipid catabolism

adipocytyes

liver

stimulate Hormone sensitive lipase to breakdown the fats

++oxidation of fatty acids

stimulate ketogenesis (because of excess acetyl Coa)

inhibit lipogenesis

INCREASE protein anabolism

muscles

++ aminoacids transport across membranes

++ RNA translation into proteins by ribosomes

++ DNA transcription into RNA to make proteins

DECREASE PROTEIN cataqbolism (protein sparing)

go to liver and generate IGF-1

growth of bone

width

length

stimulate osteoblasts

increase bone desposition on the surface

increase in bone thickness

increase the metabolism of chondrocytes

increase the secretion of cartilage in the epiphyseal cartilage

increase the conversion of this cartilage into bone

JAK/STAT pathway

MAPK and PI3K/PKB pathways

GH excess

GH deficiency

before epiphyseal closure

after epiphyseal closure

treatment

gigantism

increase in length to 8-9 feet

all tissue of the body growth rapidly

hypopituitarism

acromegaly

increase in bone thickness

growth in soft tissue (heart-kidney)

main line is surgery-2nd line: radiation

3rd line: pharmacological

Somatostatin analog

Dopamine agonists

GH receptor antagonists

octreoline

bromocreptine

pigvisomant

main cause: hypopituitarism

child

adult

treatment

pituitary dwarfism

patient becomes very short-sexual functions might be imparied

generalized symptoms

decrease muscle mass - obesity -lack of energy - accelerated aging

depends on the cause

GH is deficient

IGF-1 is deficient

Hypothalamic damage

recombinent hGH

Saizen

rIGF-1

Mecasermin

Synthesitic GHRH

Sermorelin