Endocrine Flashcards
Zona glomerulosa of adrenal gland
most superficial layer of cortex
secretes aldosterone
controlled by renin-angiotensin
Zona fasciculata of adrenal gland
middle layer of cortex
secretes cortisol/sex hormones
controlled by ACTH/CRH
Zona reticularis of adrenal gland
deepest layer of cortex
secretes sex hormones (androgens)
controlled by ACTH/CRH
Medulla of adrenal gland
secretes catecholamines (chromaffin cells) has preganglionic sympathetic fibers
Post pituitary secretion
ADH
oxytocin
from neuroectoderm
Ant pituitary secretion
FSH LH ACTH TSH prolactin GH melanotropin from oral ectoderm (Rathke's pouch)
Endocrine cells of pancreas
alpha-glucagon
beta-insulin
delta-somatostatin
Insulin secretion pathway
increased Glc, increases ATP
K+ channels close, depolarizes cell
Ca2+ channels open
Ca2+ stimulates insulin release
Transporters of glucose in membrane
Glut1-RBC/brain
Glut2-beta islet cells/liver/kidney/intestines (bidirectional)
Glut4-adipose/muscle tissue (insulin dependent)
Stimulators of insulin release
hyperglycemia
GH
beta2-antagonists
Inhibitors of insulin release
hypoglycemia
somatostatin
alpha2-agonists
Regulators of prolactin
TRH increases
dopamine decreases
Regulators of TSH
TRH increases
Somatostatin decreases
Somatostatin role
inhibitors GH and TSH
antigrowth
GnRH role
increase FSH/LH
inhibited by prolactin
Prolactin characteristics
inhibits ovulation/spermatogenesis promotes milk production inhibits GnRH release inhibited by dopamine/stimulated by TRH from ant pituitary
GH/somatotropin characteristics
linear growth & muscle mass though IGF1/somatomedian secretion
released in pulses by GHRH
increased secretion during sleep/exercise
inhibited by Glc/somatostatin
HTN
hypokalemia
ambiguous genitalia in male
17alpha-hydroxylase deficiency decreased DHT (testosterone)
Hypotension (volume)
hyperkalemia
female
pseudohermaphroditism
21-hydroxylase deficiency
masculinization
HTN
masculinization
11beta-hydroxylase deficiency
Cortisol characteristics
from zona fasiculata decreases bone formation increases epi/NE sensitivity (alpha1 receptors) on arterioles increase insulin resistance increased gluconeogenesis
Regulation of cortisol
increased by CRH/ACTH
excess cortisol decreases CRH/ACTH
PTH characteristics
increased bone resorption
increased renal Ca2+ resorption/decreased phosphate renal resorption
increases calcitriol production of kidneys
Vit D characteristics
1,25 (OH)2 in kidney
increases Ca2+/phosphate absorption in GI
also increases bone resorption
Role of calcitonin
decrease bone resorption of Ca2+
Functions of T3 (thyroid hormone)
brain maturation
bone growth
beat-adrenergic effect
increase basal metabolic rate (via Na+/K+ ATPase activity)
Regulation of thyroid hormones (T3/T4)
TRH stimulates TSH, which stimulates follicular cells to make T4/T3
T3 (-) feedback on ant pituitary
HTN wt gain moon facies buffalo hump osteoporosis
Cushing’s syndrome
increased cortisol (steroids/tumor)
also see thin skin and immune suppression
truncal obesity seen
HTN
hypokalemia
alkalosis
low plasma renin
Primary hyperaldosteronism (Conn's sydnrome) from adrenal hyperplasia/adenoma
HTN
hypokalmeia
high plasma renin
no growth on adrenal glands
Secondary hyperaldosteronism
renal artery stenosis/renal failure/cirrhosis
Skin hyperpigmentation
adrenal atrophy
hypotension
hyperkalemia
Addison’s disease/adrenal insufficiency
lack of aldosterone and cortisol
involves entire cortex of adrenals
N. meningitidis infection
DIC
acute hypotension/hyperkalemia
Waterhouse-Friderichsen syndrome
hemorrhage of adrenal glands
Episodic HTN headache 40 y/o male persperiation pallor
Pheochromocytoma
chromaffin cell tumor secreting dopamine/NE/epi
has urinary VMA (NE/epi metabolite)
tx with irreversible alpha antagonist (phenoxybenazmine) before surgery
4 y/o male
increased homovanillic acid in urine
metastasis seen throughout body
Neuroblastoma
overexpression of N-myc gene
Nontender, enlarged thyroid
Huerthle cells
cold intolerance
wt gain
Hashimoto’s thyroiditis (hypothyroidism)
assc with HLA-DR5 and lymphoma
thyroid peroxidase antithyroglobulin Abs
Pale protruding umbilicus pot bellied puffy faced child protuberant tongue
Cretinism
due to lack of fetal iodine (hypothyroidism)
mother with goiter
Tender thyroid
wt gain
post flu
sx subside after 1 wk
Subacute thyroiditis (de Quervain's) self limited hypothyroidism
Painless goiter
hard/fixed thyroid
wt gain
cold intolerance
Reidel’s thyroiditis
fibrosis of thyroid tissue
IgG4 related systemic disease
focal patches of hyperfunctioning follicular cells
increased T3/T4
Toxic multinodular goiter
mutation of TSH receptor
Bilateral proptosis
waxy discoloration of skin on ant legs
wt loss
palpitations
Grave’s disease
thyroid stimulating Ig
pretibial myxedema (skin problem)
ophthalmopathy
Thyroid growth
empty appearing nuclei
pasammoma bodies
Papillary carcinoma of thyroid
good prognosis
Orphan Annie’s eyes=empty nuclei
Decreased serum Ca2+
increased phosphate in urine
thyroid mass
sheets of cells in amyloid stroma
Medullary carcinoma of thyroid
assc with MEN 2A and 2B
produces calcitonin
Bone space filled with brown fibrous tissue
hypercalcemia
constipation
Osteitis fibrosa cystica
from excess PTH
Hypocalcemia
hyperphosphatemia
CKD
bone lesions
Renal osteodystrophy
hyperparathyroidism due to renal disease
Contraction of facial m. with tapping facial n.
occlusion of brachial a. causes carpal spasm
hypocalcemia
Hypoparathyroidism Autoimmune or DiGeorge syndrome causes tetany facial contraction=Chvostek's sign carpal spasm=Trousseau's sign
AD
hypocalcemia
short 4th/5th digits
short stature
Albright’s hereditary osteodystrophy
PTH unresponsiveness of kidney
Galactorrhea
infertility
amenorrhea
Bilateral hemianopia
Pituitary adenoma
decreased GnRH
Increased IGF-1
Glc intolerance
large hands/feet
coarse facial features
Acromegaly
usually due to pituitary adenoma
Thirst
dilute urine
concentration of urine following desmopressin
Central diabetes insipidus
no ADH production
Nephrogenic DI does not respond to desmopressin
Hyponatremia
concentrated urine osmolarity
improves with demeclocycline
SIADH
assc with small cell lung cancer/head trauma/pulmonary disease/cyclophosphamide
correct Na+ levels slowly
AD
hypocalcemia
short 4th/5th digits
short stature
Albright’s hereditary osteodystrophy
PTH unresponsiveness of kidney
Contraction of facial m. with tapping facial n.
occlusion of brachial a. causes carpal spasm
hypocalcemia
Hypoparathyroidism Autoimmune or DiGeorge syndrome causes tetany facial contraction=Chvostek's sign carpal spasm=Trousseau's sign
Hypocalcemia
hyperphosphatemia
CKD
bone lesions
Renal osteodystrophy
hyperparathyroidism due to renal disease
Bone space filled with brown fibrous tissue
hypercalcemia
constipation
Osteitis fibrosa cystica
from excess PTH
Decreased serum Ca2+
increased phosphate in urine
thyroid mass
sheets of cells in amyloid stroma
Medullary carcinoma of thyroid
assc with MEN 2A and 2B
produces calcitonin
Thyroid growth
empty appearing nuclei
pasammoma bodies
Papillary carcinoma of thyroid
good prognosis
Orphan Annie’s eyes=empty nuclei
Bilateral proptosis
waxy discoloration of skin on ant legs
wt loss
palpitations
Grave’s disease
thyroid stimulating Ig
pretibial myxedema (skin problem)
ophthalmopathy
focal patches of hyperfunctioning follicular cells
increased T3/T4
Toxic multinodular goiter
mutation of TSH receptor
Painless goiter
hard/fixed thyroid
wt gain
cold intolerance
Reidel’s thyroiditis
fibrosis of thyroid tissue
IgG4 related systemic disease
Tender thyroid
wt gain
post flu
sx subside after 1 wk
Subacute thyroiditis (de Quervain's) self limited hypothyroidism
Pale protruding umbilicus pot bellied puffy faced child protuberant tongue
Cretinism
due to lack of fetal iodine (hypothyroidism)
mother with goiter
Nontender, enlarged thyroid
Huerthle cells
cold intolerance
wt gain
Hashimoto’s thyroiditis (hypothyroidism)
assc with HLA-DR5 and lymphoma
thyroid peroxidase antithyroglobulin Abs
4 y/o male
increased homovanillic acid in urine
metastasis seen throughout body
Neuroblastoma
overexpression of N-myc gene
Episodic HTN headache 40 y/o male persperiation pallor
Pheochromocytoma
chromaffin cell tumor secreting dopamine/NE/epi
has urinary VMA (NE/epi metabolite)
tx with irreversible alpha antagonist (phenoxybenazmine) before surgery
N. meningitidis infection
DIC
acute hypotension/hyperkalemia
Waterhouse-Friderichsen syndrome
hemorrhage of adrenal glands
Skin hyperpigmentation
adrenal atrophy
hypotension
hyperkalemia
Addison’s disease/adrenal insufficiency
lack of aldosterone and cortisol
involves entire cortex of adrenals
HTN
hypokalmeia
high plasma renin
no growth on adrenal glands
Secondary hyperaldosteronism
renal artery stenosis/renal failure/cirrhosis
HTN
hypokalemia
alkalosis
low plasma renin
Primary hyperaldosteronism (Conn's sydnrome) from adrenal hyperplasia/adenoma
polydipsia
polyuria
obese 45 y/o
peripheral neuropathy
Diabetes mellitus type 2
17 y/o
ketoacidosis
low serum insulin
Diabetes type I
Type I diabetic
bleeding from the nose
Mucomycosis/rhizopus infection
Recurrent diarrhea
cutaneous flushing
R sided heart murmur
growth at the appendix
Carcinoid syndrome (neuroendocrine cells) assc with GI metastasis secretes 5HT increased urine 5HIAA niacin deficiency
Rugal thickening of stomach
recurrent ulcers
growth of pancreas
Zollinger-Ellison syndrome
gastrin secreting tumor, increasing H+ secretion
Origin of post pituitary
neuroectoderm (dienchephalon)
Origin of ant pituitary
ectoderm from orpharynx
Rathke’s pouch
Cells types assc with ant and post pituitary
ant-parvocellular
post-magnocellular (PVN and supraoptic nucleus)
Tx for hyperprolactinomia
bromocriptine (DA2 agonist)
Sheehan syndrome
postpartum necrosis of ant pituitary
due to shock/hemorrhage
decreased blood to enlarged pituitary
Reason for pallor in hypopituitarism
loss of melanocyte stimulating hormone (MSH)
Major mortality with acromegaly
cardiovascular disease
DM
