2 types exocytosis Correct Answers kiss and run- vesicle
connects/disconnects several times before contents are emptied,
low rate of signaling
full - total release of vesicle contents at once, high rate of
signaling **must be counterbalanced by endocytosis to stabilize
membrane surface area
3 methods of local control via intercellular communication
Correct Answers - gap junctions (eg. cardiac muscle)
- contact-dependent (eg. immune)
-autocrine (molecules move a small distance through interstitial
fluid
3 types meninges Correct Answers dura mater - very tough
membrane
arachnoid membrane - delicate tissue
pia mater - lies on top of brain, tethered to arachnoid by
"trabeculae"
adaptation Correct Answers MP decays over time
- stimulus may be constant, but the original voltage is not
sustained
- nocireceptors don't adapt very well (makes pain management
difficult!)
addison's disease Correct Answers - adrenal insufficiency
- symptoms: hypotension (bc decreased aldosterone),
hypoglycemia (bc decreased cortisol)
- can be chronic or acute
,- caused by destruction of adrenal cortex by autoimmunity or
infection
after-hyperpolarization Correct Answers extra voltage-gated K+
channels (and K leak channels) so greater outward K+ current,
causing MP to be more polarized than normal
*voltage-gated K+ channels open when membrane is
depolarized, much like voltage-gated Na channels
aldosterone general Correct Answers - steroid hormone
- made in adrenal cortex
- increase sodium (and water) reabsorption and potassium
secretion
- acts on distal tubule and collecting duct
aldosterone intracellular mechanism on distal tubule and
collecting duct cells Correct Answers diffuse into cell, initiate
transcription in nucleus, make new sodium and potassium
channels and sodium-potassium ATPase, prevent degradation of
apical Na channel
androgens and estrogens of zona reticularis (ACTH...) Correct
Answers - weak (less than 20% activity of testosterone, but
converted to more potent hormones in peripheral tissues)
- ACTH increases androgen production!!
- plays a role in children (male prenatal development, puberty),
source of estrogens for women after menopause
ANP Correct Answers released by atrial myocardial cells
(senses increased BV and atrial stretch) (and neurons)
- decrease Na and H2O reabsorption
, - increase K reabsorption
- suppress renin, aldosterone, vasopressin
- increase NaCl and H2O excretion (increased GFR)
- decreased sympathetic output
- decreased blood volume and BP
anterior pituitary Correct Answers releasing/inhibiting
hormones from hypothalamus travel through portal vessels
anterior and posterior pituitary (not an endocrine gland!)
arachnoid villi Correct Answers - about 1/2 CSF drains through
these into venous system
- out pouching of arachnoid tissue, sticks out through dura
matter into venous sinus
astrocytes (glycolysis) Correct Answers - provide bridge
between neurons and blood vessels with "end feet"
- efficient at glycolysis
- absorbs glucose from capillary, producing lactate as end-
product, lactate is substrate for ATP production
- remove neurotransmitters (since near synapse)
- will line up single file since following blood vessels
- regulate local blood flow
basal metabolic rate (BMR) Correct Answers energy
expenditure when resting, comfortable temperature, FASTED
benzodiazepine Correct Answers GABA agonist, decrease
excitability, sedative