pituitary Flashcards
stimulates production and release of corticosteroids by adrenal glands
ACTH
anabolic hormone released from ant. pituitary
growth hormone
stimulates production and release of T4 by thyroid
TSH
key hormone controlling reproductive process and development
FSH
stimulates ovulation and development of corpus luteum as well as production of testosterone
LH
stimulates milk production and provides sexual gradification
prolactin
2 hormones from posterior pituitary
ADH and oxytocin
vasopressin increases water absorption in kidneys
ADH
increasing uterine contractions and milk release
oxytocin
which lobe secretes hormones by negative feedback to adrenals, thyroid, and gonads
anterior pituitary
which lobe does not produce its own hormones but stores
posterior
which hormones are made in the hypothalamus
ADH and oxytocin
what is intermediate pituitary lobe do
secretes melanocyte stimulating hormone to control skin pigmentation
Acromegaly is usually caused by a ___ ___ which secretes ___. Very rarely it may be caused by at an ___ location like a pancreatic cancer
Acromegaly is usually caused by a pituitary adenoma which secretes GH. Very rarely it may be caused by at an ectopic location like a pancreatic cancer
Excessive growth of hands, feet, jaw and internal organs Doughy moist handshake Amenorrhea Headaches Weakness HTN Cardiomegaly Arthralgias and arthritis
acromegaly
Gigantism
If excessive GH occurs in childhood before the epiphyses are closed
IGF-1 levels 5 times normal
Glucose tolerance test with a GH level taken at 1 hour
Elevated Prolactin
Fasting blood sugar or glucose tolerance test – patients will usually have an insulin resistance or DM 2
acromegaly blood work
IGF-1
from what organ
how is it stimuated
from liver
excess growth hormone stimulates release of this
acromegaly blood work
- marked elevation of what
- prolactin
- glucose test when and result
IGF-1 levels 5 times normal
Elevated Prolactin
Glucose tolerance test with a GH level taken at 1 hour
Fasting blood sugar or glucose tolerance test – patients will usually have an insulin resistance or DM 2
acromegaly imaging
MRI will show pituitary adenoma in about 90% of patients and is better than CT
Radiographs: Thickened skull; Tufting of terminal phalanges, Increased thickness of heel pad
Radiographs: Thickened skull; Tufting of terminal phalanges, Increased thickness of heel pad
acromegaly imaging
acromegaly MRI or CT
MRI will show pituitary adenoma in about 90% of patients and is better than CT
acromegaly onset and it does not affect what
30s
does not affect long bones
doughy moist handshake, Carpel tunnel, deep course voice, HTN, insulin resistance, arthralgias, colon polyps, cystic acne, acanthosis nigricans, HA, spinal stenosis, temporal hemianopsia, decreased libido, ED, menstrual abnormalities, obstructive sleep apnea, macroglossia, cardiomegaly
acromegaly
main acromegaly s/s
enlargement and elongation of hands, feet, jaw and internal organs
at diagnosis of acromegaly, 10% will have what
overt heart failure with dilated left ventricle and reduced ejection fraction
IGF-1 is elevated 5 fold
adenoma
why measure prolactin levels
GH secreting tumors often co-secrete prolactin
GH secreting tumors often co-secrete what
prolactin PRL
describe glucose test for acromegaly
75 gm loading dose 1hr GTT will show failure of GH to decrease to less than 2
Treatment of acromegaly
Transsphenoidal resection of the pituitary adenoma is the primary treatment.(no larger than 2cm)
Cyberknife or gamma knife if surgical and medical approaches unsuccessful
Dopamine agonist (Cabergoline) will help to normalize GH
Somatostatin analog (Octreotide, Lanreotide acetate)
GH receptor antagonist (Pegvisomant)
what will normalize GH
cabergoline- dopamine agonist
Somatostatin analog
Octreotide, Lanreotide acetate
GH receptor antagonist
Pegvisomant
Pegvisomant
GH receptor antagonist; blocks hepatic IGF-1 production, thereby providing symptomatic relief and normalization of IGF-1 in 90% of pts
Octreotide, Lanreotide acetate
Somatostatin analog are inhibitory and may decrease tumor size
cabergoline
Dopamine agonist (Cabergoline) will help to normalize GH; suppress GH levels in some pts with acromegaly that fail surgery
what is the best measure of surgical success
normalization of GH and IGF-1 levels
blocks hepatic IGF-1 production, thereby providing symptomatic relief and normalization of IGF-1 in 90% of pts
GH receptor antagonist (Pegvisomant)
acromegalic pts have increased morbidity and mortality from what
cardiovascular disorders and progression of acromegalic symptoms
what accounts for frequent visual involvement
pituitary gland has close proximity to the optic chiasma
MRI shows a sellar lesion
acromegaly
do not get what levels in acromegaly
GH. get IGF-1
achondroplasia
dwarfism; non lethal type
failure to ossify cartilage
dwarfism
syndrome that affects 1 in 15,000-40,000 newborns
dwarfism
most common type of short limbed dwarfism
achondroplastic dwarfs
average height of an adult male and female with dwarfism
4’ 4” male; and 4’ 1” female
dwarfism- describe limbs, trunks, head, face, brows
short limbs
long and narrow trunks
large heads with midface hypoplasia
prominent brows
dwarfism
motor skills
intelligence
frequent what
delayed motor milestones
nml intelligence
frequent otitis media
neurologic complications, bowing of legs, obesity, dental problems
dwarfism
although not usually apparent at birth, pituitary dwarfism may present in male infants with what
hypoglycemia and micropenis
achondroplasia group of disorders are all caused by what
mutations in the FGFR3 gene
