L9. Neurotransmitters, Receptors, Non-neuronal cells Flashcards
(15 cards)
Opiods?
Can effect pain modulation, useful analgesics
Reward systems - addictive
Includes codeine, tramadol, morphine, and fentanyl
Ionotropic?
Fast!
The ion channel is the receptor –> neurotransmitter binding to the receptor opens the channel
- Acetylcholine - nicotinic receptors (mostly Na+ channels)
- Glutamate - AMPA/NMDA receptors
- GABA - GABA receptors (mostly Cl- channels)
Metabotropic?
Slow!
Neurotransmitter binds to receptor
–> activates intracellular signalling pathway (~cAMP) –> triggers ion channels, or cellular processes/gene expression
- Dopamine - dopamine receptors
- Noadrenaline - adrenergic receptors
- Glutamate - metabotropic glutamate receptors
- Acetylcholine - muscarinic recptors
What effect do pufferfish do?
Block voltage-gated ion channels by tetrodotoxin (TTX)
Analgesia?
Pain control (analgesia, local anaesthetic) for patients with chronic neuropathic pain without improvement to other treatments - Lidocaine or bupivacaine (longer lasting)
Reversible blockage of voltage-gated Na+ channels at the injection site (local)
Intra-articular injection (in the joint) of lidocaine immediately before a physiotherapy session relieves pain during stretching and mobilization of the affected joint, enhancing the treatment effect
Glia cells?
Support cells
Astrocytes?
- Supply nutrients
- Ensheath capillaries
- Maintain ion balance
- Blood brain barrier
- Nerve growth
She Exits Moving Behind Neville
Microglia?
- Immune cells of the CNS
- Engulf and destroy microorganisms
- Brain development
I Envy Builders
CNS cell development?
Are developed from undifferentiated stem cells that are able to divide and to form all neurons and glia cells
Not lost in adults, but capacity drops significantly with age
Developing axon have a growth cone with filopodia
The direction of growth is determined by chemotaxis and durotaxis (mechanical) from astrocytes, microglia, and effector cells
Neuron development?
1-3 years many neurons are formed
Then connections are strengthened, or refined by apoptosis programmed cell
Only specific brain regions have few remaining stem cells - limited replace/repair capacity
Neural adaptation?
All local voltage changes summate at the axon hillock (spatial and temporal summation) - FAST!
- When stimulation lasts hours to days = hyper-responsiveness - long term potentiation (LTP)
- When inhibition lasts hours to days = hypo-responsiveness - long term depression (LTD)
Neural repair?
- Nerve regeneration –> if not extensive damage, the peripheral nerve can repair itself via axonal sprouting and guiding by the
Schwann cells - A muscle fibre that will no longer be innervated will atrophy (and can eventually die)
An metabotropic receptor:
A. Does not require a neurotransmitter for activation
B. Exerts its action faster than a inotropic receptor
C. Exerts only metabolomic stimulating actions
D. Can activate both intracellular pathways and ion channels
D
Microglia cells:
A. Build the myelin sheath around CNS nerves
B. Build the myelin sheath around peripheral nerves
C. Destroy microorganisms
D. Have the primary task to maintain ion balance
C
A chemical synapse:
A. Transmits information faster than electrical synapse
B. Can not modify the amplitude of information transmission
C. Can transmit information bidirectional
D. Relies on neurotransmitters for information transmission
D
