Module 7 - Neuropharm - CG Flashcards
What is the primary excitatory neurotransmitter in the CNS?
Glutamate
Which two sources can produce glutamate?
Glucose metabolism in the Kreb’s Cycle and GABA metabolism in glial cells.
What are the two most important glutamate receptors?
AMPA and NMDA receptors.
What enzyme converts glutamine into glutamate?
Glutaminase.
How is glutamate inactivated at the synapse?
It is rapidly taken up by neighboring glial cells and converted back into glutamine by
glutamine synthetase.
What is excitotoxicity, and which neurotransmitter is primarily involved?
Excitotoxicity is excessive stimulation by glutamate leading to neuronal damage or death
due to high intracellular calcium levels.
Which ion channel is regulated by NMDA receptors?
A non-specific ion channel that allows Na+ and Ca2+ to enter while allowing K+ to leave.
Why is NMDA receptor activity important for long-term potentiation (LTP)?
It is necessary for memory formation and synaptic plasticity.
What neurotransmitter is the primary inhibitor in the CNS?
GABA (Gamma-Aminobutyric Acid).
What enzyme synthesizes GABA from glutamate?
Glutamic Acid Decarboxylase (GAD).
How is GABA inactivated after release?
Reuptake into glial cells or presynaptic neurons, followed by metabolism via GABA
transaminase (GABA-T).
Which ion does the GABA-a receptor primarily regulate?
Chloride (Cl-).
What class of drugs modulates GABA-a receptors to enhance inhibition?
Benzodiazepines (BDZs).
Which neurotransmitter imbalance is implicated in epilepsy?
Excess glutamate or insufficient GABA.
What is the mechanism of action of valproic acid in seizure treatment?
It inhibits GABA transaminase (GABA-T), increasing GABA activity.
What role do enkephalins play in pain modulation?
They act on opioid receptors to inhibit pain signals.
What is the primary receptor for enkephalins?
The mu-opioid receptor.
Which drug is a competitive antagonist for opioid receptors?
Naloxone.
What is the function of the AMPA receptor?
It mediates fast excitatory synaptic transmission by allowing Na+ and K+ flux.
What is the role of serotonin (5-HT) in pain modulation?
It is involved in descending pain inhibition by promoting enkephalin release.
What is cortical spreading depression (CSD), and what condition is it associated with?
CSD is a wave of neuronal depolarization linked to migraines.
Which two neurotransmitters are co-released with glutamate in pain pathways?
Substance P (SP) and Calcitonin Gene-Related Peptide (CGRP).
What is the gate theory of pain modulation?
The concept that non-painful stimuli (A-beta fiber activation) can inhibit pain signals via
inhibitory interneurons.
How do benzodiazepines enhance GABA activity?
They increase chloride ion conductance at the GABA-a receptor, enhancing inhibitory
effects.