Transmitters and Excitability

Question 1

why does resting potential fall in development?

Answer 1

New channels and pumps, glia increase and extracellular K levels decrease from 35mM to 3mM

Question 2

What are the two principle routes of action potential development?

Answer 2

Long Ca dependant then short Na dependent.

Short Na dependant

Question 3

what are Rohon Bend cells?

Answer 3

They are transient population of neurons in embryonic vertebrate. They are mechanosensory cells of the dorsal spinal cord..

Question 4

Delayed rectifiers

Answer 4

allow current to pass one way. open with a delay after threshold is met.

Question 5

Calcium channel waves influence process growth and differetiation give three examples of the latter.

Answer 5

xenopus expression of GABA
myocyte expression of AchR delta
Mouse neuron expression of enkephalin

Question 6

Name the 4 changes in receptors during development

Answer 6

Populations, subunits, localisation, efficacy

Question 7

Adutlt GABA receptors are

Answer 7

inhibitory

Question 8

GABA a is Z and GABA b is Y

Answer 8

Z is inotropic Y is metabotrophic

Question 9

In development GABAa polarize how?

Answer 9

Imature neurons have high cl conc inside. cl influx along with ca and na. in imature more NKCC1 expression in mature more KCC2 so cl and k out.

Question 10

NMDA receptors are variable give examples

Answer 10

Developmentally regulated mg blocks

cortico neurons in vitro (change in subunit expression and antagonist affects on synaptic currents)