3/7 endo Flashcards
A drug is virtually eliminated after how many half lives?
-5
t1/2 = Vd (.7)/Cl
Acute viral hepatitis
-do you see necrosis or apoptosis?
-both
Councilman body
- apoptotic hepatocytes
- acidophillic
IV drug user w/hepatitis
-which hepatitis most likely?
-Hep C
beta-glucoronidase
- who releases it?
- what does it lead to?
- following infection of biliary tree, injured hepatocytes and bacteria release this enzyme.
- unconjugates bili = more unconjugated bili in bile = brown pigment stone.
Progesterone & gallstones
- slows gallbladder emptying
- reduces bile acid secretion
- gallbladder hypomotility => stones
Why are pregnant or OCP using women more at risk for gallstones?
- inc cholesterol synth via estrogen.
- gallbladder hypomotility via progesterone.
Bimodal distribution of plasma drug levels
- think of what?
- most drugs = unimodal
-fast v slow acetylators.
What is the most common benign liver tumor?
- cavernous hemangioma.
* do NOT biopsy these! risk of hemorrhage!
Thyroid diverticulum
- arises from where? descends to where?
- connected to tongue via?
- arises from floor of primitive pharynx, and descends into neck.
- Connected to tongue by thyroglossal duct, which normally disappears but may persist as pyramidal lobe of thyroid.
pyramidal lobe of thyroid
-persistence of what?
thyroglossal duct
Normal remnant of thyroglossal duct
Foramen cecum
Foramen cecum
Normal remnant of thyroglossal duct
Most common ectopic thyroid tissue site?
Tongue
-presents as mass at base of the tongue.
Presents as an anterior midline neck mass that moves with swallowing or protrusion of the tongue
Thyroglossal duct cyst
Adrenal cortex derived from…
mesoderm
Adrenal medulla derived from..
neural crest
Is aldo secretion controlled by ACTH?
NO
-AT2 and hyperkalemia.
adrenal medulla
-under control of what?
Blood pressure
-sympathetic response
Does LH affect steroid hormone synthesis in adrenals?
No
-only affects gonadal cells.
Neuroblastoma vs pheochromocytoma
-which one causes HTN?
- pheo causes episodic HTN.
- neuroblastoma rarely causes HTN.
Neuroblastoma
-presentation
- often presents w/abdominal distention.
- it typically crosses the midline (unlike Wilm’s tumor).
Hypophysis
-what is it?
Entire pituitary
What protein transfers ADH & oxytocin from hypothalamus down to post. pit?
-mutations in this protein can lead to what?
- neurophysins
- point mutations to neurophysin 2 underlie most cases of hereditary hypothalamic diabetes insipidus.
Post pit. derived from what?
Neuroectoderm
Ant pit. derived from what?
Oral ectoderm (Rathke pouch).
Ant. pit hormones
-alpha or beta subunit: which determines hormone’s specificity?
β subunit—determines hormone specificity.
Ant. pit hormones:
-Same α subunit shared by which hormones?
TSH, LH, FSH, and hCG.
Ant. pit hormones:
- which hormones = acidophils?
- mnemonic?
- GH, prolactin.
- GPA: GH, Prolactin = Acidophils.
Ant. pit hormones:
- which hormones = basophils?
- mnemonic?
- B-FLAT
- basophils - FSH, LH, ACTH, TSH
Why is C-peptide a good marker for insulin secretion?
- 1:1 secretion w/insulin
- does not undergo significant first pass metabolism
- not included in exogenous insulin
Which GLUT transporter is the glucose sensor for liver/pancreatic beta cells?
GLUT2
glucose vs insulin
-which can cross the placenta? can both?
- glucose can cross.
- insulin can not cross.
Insulin-independent glucose uptake:
-mnemonic:
BRICK-L
-Brain, RBCs, Intestine, Cornea, Kidney, Liver.
GH influence on insulin levels
- causes insulin resistance.
- this increases insulin release.
beta-2 agonists
-effect on insulin release
-inc. insulin release
but inc. glucagon release more i believe
Glucose influence on GH
-glucose should inhibit GH release
Insulin
- pathway for insulin release & protein/fat/glycogen synth:
- pathway for txn alteration:
- insulin release + synthesis: IP3/PKC
- txn alteration: RAS/MAP kinase
CRH from hypoT stimulates release of what?
ACTH, MSH, β-endorphin
*POMC = precursor to these 3
Dopamine
-effect on PRL?
inhibits prolactin secretion
What prevents lactogenesis during pregnancy?
-during pregnancy, the high amount of E & P made by
placenta will prevent prolactin from causing lactogenesis.
Somatostatin inhibits release of which pituitary hormones?
- GH, TSH
* octreotide used to treat acromegaly.