Neurotransmitters Flashcards
What types of effect can neurotransmitters have?
Excitatory or Inhibitory
What do Excitatory neurotransmitters do?
Stimulate the brain
Receptor proteins trigger Na+ channels to open to allow Na+ to enter the post synaptic neuron
Can cause depolarization if the threshold is crossed ~ then will generate an AP
What Inhibitory neurotransmitters do?
Trigger polarization
Receptor proteins trigger K+ ions to flow out
Makes the postsynaptic neuron to be HP
What happens to neurotransmitters after they have had their effect?
Enzymes break them down, and then they are reabsorbed
What is Acetylcholine? What happens if it stays in the cell?
Crosses the neuromuscular junction (Synapse between motor neuron and muscle cell)
It’s Excitatory - causes depolarization and contraction of muscle fiber
If acetylcholine stays in the cell muscles cells wouldn’t repolarize and would stay contracted (excited)
How is Acetlycholine broken down?
With Cholinesterase.
It’s an enzyme
Released into the synapse
Breaks down AC so it can be removed from the protein receptors
The ions channel can then close and the membrane will repolarize in a fraction of a second
What is Norepinephrine? What happens if too much is made?
It’s a Hormone
Used by the brain and some autonomic neurons body
Compliments Epinephrine (adrenaline) readied to respond in danger of stressful situations
Overproduction can result in:
Increased BP
Anxiety
Insomnia
What is Dopamine? What happens in excess and not enough production?
Both Excitatory and Inhibitory
Affects brain synapses in control of body movements
Linked to sensations of pleasure (i.e. eating)
In extreme cases
Excessive production = Schizophrenia
Non enough production = Parkinson’s disease
What is Serotonin? What happens if Inadequate amounts are produced?
It regulates temperature and sensory perception
Involved in mood control
Inadequate amounts = depression
What are Endorphins? What happens if you have a deficiency?
Acts as natural pain relievers in synapses in the brain (also affects emotional areas of the brain)
Deficiency is linked to risk of alcoholism
