Block 3 Terms

Question 1

Resting potential

Answer 1

channel specificity: non gated K+ and Cl- channels; some non gated Na+ channels
gating mechanism: none
properties: usually steady; from -35 to -70mV (~-60mV)

Question 2

Action potential

Answer 2

channel specificity: independently gated Na+ and K+ channels
gating mechanism: voltage
properties: all or none; 100mV in amplitude; 1-10 msec in duration

Question 3

Increased conductance EPSP

Answer 3

channel specificity: non-voltage gated channels; nonselective for univalent cations
gating mechanism: chemical (extracellular binding site)
properties: graded, fast, several msec in duration, several mV in amplitude
-able to summate!

Question 4

Increased conductance IPSP

Answer 4

channel specificity: non-voltage gated channels for K+ or Cl-
gating mechanism: chemical (extracellular binding site)
properties: graded, fast, several msec in duration, several mV in amplitude

Question 5

Decreased conductance EPSP

Answer 5

channel specificity: K+ leak channels
gating mechanism: chemical (GPCRs, then a second messenger)
properties: graded, fast, several msec in duration, several mV in amplitude

Question 6

what is the order of norepinephrine synthesis?

Answer 6

• tyrosine–>levo-DOPA (enzyme=tyrosine hydorxylase)
• levo-DOPA–>dopamine (enzyme=DOPA decarboxylase)
• dopamine–>norepinephrine (enzyme=dopamine beta-hydorxylase)

Question 7

neurotensin

Answer 7

13 aa long; located in prefrontal cortex; hypothalamus; midbrain; always co-loalized with dopamine (the two transmitters are utilized by the same neurons)

Question 8

Neurotensin traits

Answer 8

large, dense core vesicles
packaged at the golgi
release anywhere in terminal
used once
global increase in calcium
high frequency firing

Question 9

Norepinephrine traits

Answer 9

small vesicles
filled at terminal
only active zone release
recycled, refilled
local increase
low frequency