Ionic regulation in neuronal development

Question 1

What controls the electrical activity of neurons?

Answer 1

Ion transporters and ion channels

Question 2

What is the electrochemical gradient?

Answer 2

The chemical gradient (gradient of a given ion) + the electrical gradient (charges on either side)

Question 3

What is the equilibrium potential and reversal potential?

Answer 3

Equilibrium potential: the membrane potential where the net flow of ions though any open channel is 0

Reversal potential (Erev): the membran potential where the net flow of ions though a specific channel is 0

Question 4

Where is the ion concentration typically measured?

Answer 4

In the neuron and in the interstitial fluid (the fluid outside of the neuron)

Question 5

What is the one ion, whose concentration changes during development?

Answer 5

Chloride

Question 6

What are the two main proteins regulating chloride concentration during development?

Answer 6

KCC2 and NKCC1

Question 7

What neurotransmitter causes influx of chloride, and what is the result?

Answer 7

GABA causes influx of chloride which leads to hyperpolerization

Question 8

What determines the chloride concentration in a neuron?

Answer 8

The amount of either one of the chloride transporters (and the balance of the two)

Question 9

How can depolarizing GABAergic signalling affect developing neurons?

Answer 9

1) They can release tropic factors
2) The can develop and differentiate
3) It influences network function

Question 10

How can GABA inhibit neurons?

Answer 10

Via hyperpolerizing inhibition or shunting inhibition

Question 11

How does pH affect neuronal excitability?

Answer 11

An increase in pH enhance neuronal excitability and a fall in pH has the opposite effect