Pharmacology of the CNS Flashcards
What are the criteria for a neurotransmitter? (NT)
- Presence
- Stored in vesicles
- Release
- Effect
- Termination of effect
What are some properties of transmitters in the central nervous system (CNS) ?
- They are ALWAYS agonists
- They can produce fast or slow effects
- They can excite or inhibit
- They are determined by receptors
Ion channels — SLOW — neurotransmission
2nd messengers — FAST — neuromodulation
What are the major EXCITATORY and INHIBITORY transmitters in the brain?
Excitatory: GLUTAMATE
Inhibitory: GABA
Which neurotransmitters have mixed effects?
Acetylcholine (ACh)
Noradrenaline (NA)
Dopamine (DA)
Serotonin (5-HT)
What kinds of molecules are substance P and opioids?
Peptides
Is substance P excitatory or inhibitory?
Are opioids excitatory or inhibitory?
Substance P — excitatory
Opioids — Inhibitory
Is Nitric Oxide (NO) excitatory or inhibitory?
Is Adenosine excitatory or inhibitory?
NO and adenosine are BOTH excitatory.
Which receptors does Glutamate bind?
How do these receptors differ in their properties?
And what about for substance P?
AMPA — Fast
Kainate — Fast
NMDA — Delayed
Metabotropic (GPCR) — Slow
Substance P: Neurokinin 1 — Slow
Which two neurotransmitters are present in small amounts in the nervous system?
Substance P and Opioids
State some processes in which Glutamate plays a crucial role.
Pain — wind-up, LTP in spinal cord
Memory — LTP, etc. in hippocampus
Epilepsy — forebrain
Development — neuronal contacts
Cell death — excessive activation of Glutamate receptors such as NMDA results in excess influx of calcium, which increases osmotic pressure, thereby activating enzymes which increase [NO] subsequently releasing free radicals which leads to death.