Anatomy and Physiology: Neurotransmitters and Glial Cells

What is Acetylcholine and what does it do?

• parasympathetic NS

• decrease heart rate

• decrease blood pressure

• increase digestion

• causes muscle contraction (in synaptic gap)

• excitatory (excites muscles to contract) or inhibitory (lowers BP)

What is Glutamate and what does it do?

• helps with vision in the retina

• released based on amount of light available

• bright conditions = decreased glutamate

• dark conditions = increase glutamate

What is Epinephrine/adrenaline and what does it do?

• comes from adrenal gland

• increase heart rate

• increase muscle contraction and strength of contraction

• fight or flight

What is Norepinephrine and what does it do?

• excitatory or inhibitory

• comes from adrenal glands

• increase blood vessel constriction

• decrease blood flow in GI

• fight, flight, or FREEZE

What is Serotonin and what does it do?

• sleep, anxiety, thermoregulation

• SSRI= reuptake inhibitors (stops reuptake = stays in synapse)

What is Dopamine and what does it do?

• Excitatory NT

• found in basal ganglia (starts/stops movements)

• decreased amounts found in Parkinson’s patients

• emotional reward

• MAOI’s keep serotonin in synapse by NOT breaking down monoamines (monoamine oxidase inhibitor)

What is GABA and what does it do?

• inhibitory in CNS

• decrease stress

• helps with sleep

• calms nervous system, promotes relaxation, regulates mood

What is Glycine and what does it do???

• inhibitory

• helps with sleep

What are endorphins and what do they do?

• inhibitory in CNS and PNS

• decreases pain

• can produce euphoria

• involved in getting a “second wind”

What are the CNS support (glial) cells?

• Astrocytes

• Ependymal cells

• Microglial cells

• Oligodendrocytes

What do astrocytes do?

• maintains BBB

• adds synapses

• assists with neurological development

• clears K+ and NT from CNS synapse

What do ependymal cells do?

• makes CSF

• lines brain ventricles, central canal of spinal cord

• have cilia (helps move CSF down spinal cord)

What do microglial cells do?

• phagocytes (cellular Mr. Gilly)

• responds to infections

• found in CNS

What do oligodendrocytes do?

forms myelin in CNS

What are the PNS support cells?

• Satellite cells

• Schwann cells

What do Satellite cells do?

• covers ganglia cells in PNS

• electrically insulates cell body

• separates neural cell bodies from interstitial fluid

What do Schwann cells do?

• creates myelin in PNS

• moves AP down axon faster