PBL case
The name of our patient this week.
WHO is Maeve Sanders?
The hormone class of epinephrine/norepinephrine.
What is amines/tyrosine derivatives?
Ref: Roadmap slides.
The neurotransmitter receptors that are ligand-gated channels allow efflux of K+ and influx of Na+ and in some cases Ca2+.
What is Nicotinic ACh receptors?
Ref: First Aid, p. 235
The symptom triad that is associated with autoimmune disorders.
What is fatigue + arthralgia + cognitive complaints?
"Associated with autoimmune disorders (especially systemic lupus erythematosus, hypothyroidism, RA, fibromyalgia), but also anemia, depression, post-viral syndrome, or chronic infections (e.g., Lyme disease, EBV)." Ref: PBL case
The two main calciotropic hormones the determine serum calcium levels through three dynamic processes and feedback-loop mechanisms.
What is calcitriol and parathyroid hormone?
"Calcitriol (1,25-dihydroxyvitamin D 3 ) enhances absorption from the small intestine, and parathyroid hormone (PTH) promotes calcium mobilization from the bones and reabsorption in the kidneys, causing an increase in serum calcium levels." Ref: PBL case
The G-protein class for the adrenergic receptor alpha-1?
What is Gq?
Gq protein -> phospholipase C -> PIP2 -> IP3 & DAG -> increased Ca2+ (IP3) -> protein kinase C (DAG & Ca2+) -> smooth muscle contraction
Ref: First Aid p. 237
A 40-year-old man has low serum calcium and elevated phosphate: this part of the kidney is most directly responsible for the impaired excretion of phosphate.
What is the proximal tubules of the kidney?
Ref: PBL (Day 2 question)
The ADH receptor that regulates blood pressure.
What is V1-receptor?
"An increase in serum osmolality or a decrease in serum volume stimulates the hypothalamus, which signals the posterior pituitary to release ADH. The hormone then acts on aquaporin channels in the medullary collecting duct of the kidney, increasing water reabsorption. This leads to higher urine osmolality and lower urine volume, restoring serum osmolality and volume. A negative feedback mechanism inhibits further ADH release when serum osmolality decreases and serum volume increases." Ref: First Aid
This cholinomimetic agent serves as a challenge test for diagnosis of asthma.
What is methacholine?
MOA: Direct agonist. Stimulates muscarinic receptors in airway when inhaled. Ref: IFS synthesis, First Aid p. 239.
The procedure that may elicit a contraction of the ipsilateral facial muscles by tapping the facial nerve just anterior to the ear.
What is the Chvostek’s sign?
"The response ranges from twitching of the lip to spasm of all facial muscles and depends upon the severity of the hypocalcemia."
Ref: UpToDate ("Clinical Manifestations of Hypocalcemia")
The hypothalamic-pituitary-target organs of somatotropin.
What is the liver (-> bones & muscle) and the adipose tissue?
Somatotropin = Growth Hormone (GH). "Stimulates linear growth (bones) and muscle mass through IGF-1 (somatomedin C) secretion by liver." Ref: First Aid, p. 333
GH stimulates growth in all tissues except brain. GH "diabetogenic" Ref: IFS synthesis slides
A 25-year-old female at 32 weeks gestation begins taking a drug to delay the onset of preterm labor and notices tremulousness in her hands after the first dose: this type of receptor is most likely involved in this drug effect.
What is beta2-adrenergic?
"Rationale: Stimulation of beta-2 receptors on skeletal muscle cells causes increased contractility and may lead to muscle tremors. B2 (Gs)--> increased AC --> increased cAMP --> activation of PKA --> increased calcium --> skeletal muscle contraction" Ref: IFS synthesis slides
These are four of the seven functions of triiodothyronine in the peripheral bloodstream.
What is
Brain maturation
Bone growth (synergism with GH and IGF-1)
B-adrenergic effects.
Basal metabolic rate increase (via increased Na+/K+-ATPase)
Blood sugar (increased glycogenolysis, gluconeogenesis)
Break down lipids (increased lipolysis)
Babies - stimulates surfactant synthesis
?
Triiodothyronine = T3. Ref: First Aid p. 335
The hormones that have IP3 as a 2nd messenger.
What is gonadotropin-releasing hormone (GnRH), oxytocin, ADH (V1), thyrotropin-releasing hormone (TRH), histamine (H1), angiotensin II?
“GOAT HAG": GnRH, Oxytocin, ADH (V1), TRH, Histamine (H1), Angiotensin II. Ref: FirstAid
This cholinergic receptor subtype decreases AV node conduction velocity and increases effective refractory period.
What is M2 (Gαi)?
M2 does a lot, including "decreases heart rate, AV node conduction velocity, and atrial contractility"
Ref: IFS Roadmap slides; First Aid p. 237