endo DIT Flashcards
cAMP modifying hormones (11)
FSH LH TSH hCG ACTH MSH GHRH PTH Calcitonin glucagon V2 vassopressin
IP3 modifying hormones(4)
GNRH
TRH
Oxytocin
vasopressin (v1)
Tyrosine kinase receptor modulators
GH Insulin insulin like growth factor Platelet derived growth factor fibroblast growth factor Cytokines prolactin
cGMP modulators (2)
NO
ANP
the vasodialators
Preganancy leads to an increase of what liver product that may affect hormone affects
binding globulin decreasing the amount of free active hormone
Thyroid - TGH for example
Steroid receptor modulated hormone (5)
estrogen, progesteron, testosterone glucocorticoids aldosterone Thyroid hormone Vit D
Availabilty of binding hormone affects 2 things
amount of free hormone
activity of steroid hormone
increased sex binding hormone may have what affect on men?
gynectomastia due to decreased free testosterone
decreased sex binding hormone in women may have what effect in women?
hurtusism
ACTH and MSH are synthesized by what precursor?
Clinical relevance?
POMC
Leads to hyperpigmentation w/ primary adrenal insufficency
Hyperprolactenima due to? (4)
pregnancy/ nipple stim
stress
prolactinoma
dopamine antagonists ) haloperidol, risperidone, domperidone, metoclopramide, methydopa
Symptoms of hyperprolactinemia in
pre meno women
post meno?
Men
hypogonadism -> infertility, oligo/amennorhea, rarely galatorrhea
post meno - asymptomatic, maybe galactorrea
Men - (low testosterone)low labido, impotence, infertility, gynectomastia, rarely galactorrhea
remember, prolactin inhibits FSH and LH
Clinical uses of octreotide(3)
pituitary excess
-acromegaly, thyrotropinoma, ACTH secreting hormones
GI endocrine excess
-Zollinger ellison syndrome, carcinoid, VIPoma, glucagona, insulinoma
Need to reduce splanchnic circulation
-portal HTN, bleeding peptic ulcers
infertility, galactorrhea and bitemporal hemanopsia
prolactinoma
inability to breastfeed, amenorrhea, cold intolerance
sheehan syndrome
Which hormones share a common alpha subunit(4)
TSH
LH
FSH
b hCG
anterior pituitary is derived from
rathke’s pouch
surface ectoderm
posterior pituitary is derived from
neuroectoderm
ADH is stimulated w/ ?(3)
Decreased w?(3)
nicotine
opiates
high serum osmolarity
low volume contraction
ethanol
atrial naturetic factor
low serum osmolarity
Oxytocin important w/
stimulated w?
pregnancy and breast feeding
uterine contraction ( return to normal size/clamp bleeding)
milk ejection
cervical dilation
inhibited w/ alcohol and stress
inhibit feeds back and blocks
FSH
progesterone and testosterone feedback on
LH
ACTH is stimulated to release w/(2)
Stress
CRH from the hypothalamus
TSH is released from?
inhibited by?
Stimulated by?
TSH from the pituitary
inhibited by T3 and T4 levels
Stimulated by TRH from hypothalamus
Prolactin leads to inhibition of ?
Prolactin stimulated by?
ovulation via blocking of LH and FSH
- stimulates milk production and breast development
stimulated to release by TRH and less Dopamine inhibition
GH effects (4)
increases growth
decreases glucose uptake (insulin resistent- mobilize gluc)
increase protein synth
increase organ size and lean body mass
upstream control of GH (2)
other regulators of release(environmental)
GHRH - releases
GHIH (somatostatin)
+: exercise, sleep, hypoglycemia, puberty, estrogen, stress, endogenous opiods
-: obesity, hyperglycemia, pregnancy
Downstream response to increase of GH
increase of IGF 1
Rx for prolactinoma
dopamine agonists
- bromocriptine
- cabergoline
Presentation of Acromegaly
large tounge deep voice large hands/feet coarse facial feature impaired glucose tolerance
Diagnosis of acromegaly (2)
measure IGF1 - more stable vs pulsitile GH
failure of suppression of GH from the pituitary adenoma w/ glucose given
Zona glomerulosa secretes
responds to
Aldosterone
renin
Zona fasiculata secretes?
responds to
cortisol
ACTH and CRH
Zona reticularis secretes?
Responds to?
androgens
ACTH and CRH
Adrenal tumor in adult vs kids
One key difference
Pheochromocytoma in adults -> episodic periods of hypertension
Neuroblastoma in kids -> maybe chronic HTN.
Symptoms of a pheochromocytoma (4)
HA, Sweats, Tachy, Eposodic HTN
Fetal adrenal gland is important in
secretion of cortisol for fetal lung maturation
responds to CRH and ACTH
ketoconazole acts to block what enzyme?
desmolase
-conversion of cholesterol -> pregnenolone
ACTH acts on what enzyme to encourage hormone synthesis?
Desmolase
Angitension II acts on adrenal steroid synthesis by increasing the action of what enzyme
aldoserone synthase
One thing in common w/ adrenal hyperplasia
all have decrease production of cortisol
- > ACTH ramps up
- > stimualtes adrenal cortex
- > adrenal hyperplasia
Enzyme responsible for converting testosterone to a more active enzyme
Blocked by what drug
5 alpha reductase
blocked by finasteride
estone, estradiol and estriol all need what enzyme to be made?
Aromatase
Features of 3 beta hydroxysteriod deficiency? (3)
Inability to produce
- glucocorticoids
- mineralcorticoids
- androstenedione-> testosterone or estrone
- estrogens
Excessive Na excretion in the urine (salt wasting)
Early death
What features are characteristic in 17 alpha hydroxylase deficiency
inability to produce androgens/sex hormones and cortisol
-> phenotypic female that is unable to mature (no androstendione)
Hypertension w/ everything being shunted to aldosterone production
-Na and water retention
Desmolase is responsible for what
converting cholesterol to pregnenolone starting the adrenal steroid pathway
rate limiter
What features are characteristic of a deficiency in 21 alpha hydroxylase? (3)
Can’t make cortisol or aldosterone ->
Increased ACTH
Hypotension and salt wasting w/ou Aldosterone
Masculinization w/ everything shunted to the right (androstenedione)
What features are characteristic of 11 beta hydroxylase deficiency?
Inability to produce Aldosterone and Cortisol
Increased ACTH
Increased production of 11 deoxycorticosterone
-Acts as a weak aldosterone -> HTN
masculinization with a shift to sex hormone production (androstenedione)
2 deficiencies characteristic in hypertension
11 beta hydroxylase
17 alpha hydroxylase
2 deficiencies characteristic in masculinization
21 hydroxylase
11 beta hydroxylase
deficiency characteristic in hypotension
masculinization of feminization
21 hydroxylase
masculinization
Cortisol maintains BP how?
increasing alpha 1 receptors on the vasculature increasing sensitivity
Cortisol functions/effects on the body (5)
BBIG
Maintain BP increasing alpha receptors on vasculature
Decreases bone formation
Anti inflam/immune suppresive
-neutropenia w/ adhesion disruption, inhibits prostaglandin production, block IL2
Insulin resistance (diabetogenic)
Gluconeogenesis/lipolysis and proteolysis ( increases enzyme expression)-> mobilizes sugars
Why is there a rise in WBC after giving a glucocorticoid
neutropenia transient due to mobilization of WBC stores in the vasculature
Regulation of cortisol 3 steps
CRH from the hypothalamus
- > Pituitary releasing ACTH
- > ACTH acts on the adrenal cortex (desmolase) to increase production of cortisol in the zona fasiculata
What can induce prolonged secretion of cortisol
chronic stress
Symptoms of Cushing Syndrome
BAM CUSHINGOID
Buffalo hump
Amenorrhea
Moon Fascies
Crazy Ulcers (peptic) Skin ∆s (striae, acne) HTN Infection Necrosis of femoral head glaucoma.cataracts Osteroperosis Immunosuppression DM
4 Causes of Cushing Syndrome
Iatrogenic (exogenous steriods - #1)
Pituitary Adenoma - Cushings disease (ACTH)
Ectopic ACTH production - small cell
Adrenal adenoma (primary high cortisol)
Dexamethasone suppression test w/ high dose will suppress cortisol of which cause of cushing syndrome?
Suppreses pituitary adenoma
ACTH levels to differentiate between adrenal adenoma and small cell - both unsuppresed
- high ACTH in ectopic (small cell)
- low ACTH in adrenal adenoma
Presentation of HTN, hypokalemia and metabolic alkalosis due to
Conn Syndrome
- Primary hyperaldosteronism
Have a low renin level
primary hyperaldosteronism name?
Triad of symptoms
Conn syndrome
See:
- Hypertension
- Hypokalemia
- metabolic alkalosis
Rx for Conn syndrome (2)
epleronone and spironolactone
Surgery
prevent hyperaldosertone
Secondary hyperaldosteronism due to: (4)
renal artery stenosis
chronic renal failure
CHF
hypo protein states (edema perceived fluid loss)
- cirrosis
- nephrotic syndrome
Going to have high renin levels (appropriately)
Fludrocortizone
highly active synthetic mineral corticoid
Stimulation of Aldosterone
decreased aldosterone secretion
Decreased
-high Na
Increased in
- low Na or volume
- Hyperkalemia
Addisons is most commonly due to
Presentation
autoimmune attack of the adrenal cortex -> chronic primary adrenal insufficiency ( less aldosterone, cortisol)
–Less commonly: TB and METs
low aldosterone and cortisol ->
- hypotension
- skin pigmentation
- hyperkalemia
- acidosis
- malaise
- anorexia
- fatigue
- weight loss
Primary adrenal insufficiency can be distinguished from secondary adrenal insufficiency by :
Increased amount of ACTH in primary adrenal insufficiency
Decreased in secondary adrenal insufficiency (problem is in the pituitary
Secondary adrenal insufficiency presents as?
Due to
less ACTH due disruption of the pituitary ->
malaise
fatigue
weight loss
anorexia
NO skin pigmentation (no POMC)
NO hyperkalemia/hypotension (Aldosterone from renin)
How do you have hypotension w/ Addison’s
chronic primary adrenal insufficiency
no alpha 1 upregulation w/ cortisol
No aldosterone leading to water and Na retention
Cause of acute adrenal insufficiency
adrenal hemorrhage w/ Nessieria meningitidia
(waterhouse frederichsen syndrome
- Septic
- DIC
endotoxic shock
Urine product detecting pheo?
Serum product looking for a pheo?
VMA ( vanilla mandelin acid) in urine
Normetanephrine and metanephrine in serum
catecholamine breakdown products
Pheos can be associated w which 3 tumor syndromes
MEN 2A
MEN 2B
neurofibromatosis 1
Erythropoeitin can be secreted in 4 tumors
Pheochromocytoma
Renal cell carcinoma
hemangioblastoma
hepatocellular carcinoma
Medical treatment for a pheochromocytoma?(3 steps
1st manage the BP w/ alpha 1 antagonist - phenoxybenzamine
- maybe give a beta blocker
- surgically remove the chromatin cell/adrenal medulla cancer
Rule of 10s w/ a pheochromocytoma (5)
90% benign 90% adults 90% adrenal - occasionally extra renal 90% do not calcify 90% unilateral
most common tumor of the adrenal medulla in kids
presentation/location?
test for urine?
neuroblastoma
tumor can be anywhere in the sympathetic chain 40% adrenal
less likely episodic HTN
homovanillic acid (dopamine breakdown) in urine
neuroblastoma is associated w. over expression of this oncgene
Histological stain to help differentiate
n-myc
can stain for neurofilaments
Bombeison tumor marker associated w?
neuroblastoma
MEN 1 tumors
associated mutation
mutation in p53
3 Ps
Pituitary adenoma
Parathyroid adenoma**
Pancreatic tumors (VIPoma, gastrinoma, insulinoma, zollinger ellison, glucagonomas)
MEN 2a tumors
associated mutation
mutation in ret gene
PP’s and M
Medullary thyroid carcinoma* (secretes calcitonin)
Pheochromocytoma
Parathyroroid tumor
MEN 2 B tumors
associated mutation
mutation in ret gene
1P and 2 Ms
Medullary Thyroid Carcinoma
Pheochromocytoma
Mucosal neuromas (ganlioneuromatosis of the Gi and oral cavity)
MEN syndrome inheritence
all auto recessive
presentation of kidney stones or stomach ulcers w/ weigh loss
be concerned of what?
MEN 1
- parathyroid tumor -> PTH -> excess Ca
- Pancreatic tumor -> gastrinoma
most common cause of Conn syndrome
adrenal hyperplasia
Thyroid is derived from what tissue in what location?
ectoderm
originates from the floor of the primitive and descends into the neck via the thyroglossal duct
foramen cecum is site of origination and most common site of ectopic thyroid tissue
anterior midline mass that moves with swallowing is what?
Derived from
thyroglossal duct cyst that is due to persistent thyroglossal duct
Function of T3 and T4
ramps up metabolism
- bone growth (synergy w/ GH)
-CNS maturation
increase in beta 1 receptors of the heart
increased basal metabolic rate via increased Na/K atpase activity
increased glycogenolysis, gluconeogenesis. lipolysis
Thyroxine binding globulin increased w?
Decreased w?
resulting lab values
Increased TBG in pregnancy and OCP use
- leads to increase in total T4 and T3 w/ binding of free hormone
- percieved depletion of free hormone leads to increase in release which is again bound up -> normal/elevated T3/T4
TSH can be low due to similarity to beta hCG
Enzyme responsible for oxidation and organification go iodide?
Peroxidase
Iodide is brought into the follicular cell via?
Bound to what AA residue
Na/I cotransporter
then oxidized to Iodine and bound tyrosine AA residue on thyroglobulin (organification)
2 drugs to prevent thyroid hormone synthesis
Which is preferred overall?
Which is preferred in pregnancy
propylthirouracil
- blocks peripheral conversion of T4-> T3
- used in 1st trimester
- generally worse SFx profile w/ agranulocytosis, liver dysfunction
methimazole
- preferred over all
- used in 2nd and 3rd trimester only due to risk aplastic cutis in 1st
Symptoms of hyperthyroidism
heat intolerance -> due to production/metabolism weight loss hyperactivity diarrhea increased reflexes pretibibial myxedema - graves warm moist skin tachycardia
Lab value used to screen for hyperthyroidism
TSH would be low
-very responsive to small changes in T3 and T4