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Today& #39;s #PharmPhriday 
https://abs.twimg.com/emoji/v2/... draggable="false" alt="🧵" title="Thread" aria-label="Emoji: Thread"> is on the GABA-A receptor and benzodiazepines!
This receptor is pentameric (5 subunits), and as the name implies, it is the receptor for the inhibitory neurotransmitter, GABA. There are 2 α, 2 β, and 1 other subunit.
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This receptor is pentameric (5 subunits), and as the name implies, it is the receptor for the inhibitory neurotransmitter, GABA. There are 2 α, 2 β, and 1 other subunit.
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is on the GABA-A receptor and benzodiazepines!This receptor is pentameric (5 subunits), and as the name implies, it is the receptor for the inhibitory neurotransmitter, GABA. There are 2 α, 2 β, and 1 other subunit.1/7" title="Today& #39;s #PharmPhriday https://abs.twimg.com/emoji/v2/... draggable="false" alt="🧵" title="Thread" aria-label="Emoji: Thread"> is on the GABA-A receptor and benzodiazepines!This receptor is pentameric (5 subunits), and as the name implies, it is the receptor for the inhibitory neurotransmitter, GABA. There are 2 α, 2 β, and 1 other subunit.1/7" class="img-responsive" style="max-width:100%;"/>
But wait, there& #39;s more! There are subtypes of subunits https://abs.twimg.com/emoji/v2/... draggable="false" alt="🤯" title="Explodierender Kopf" aria-label="Emoji: Explodierender Kopf"> These determine what the receptor will respond to. For example, a GABA-A receptor is only sensitive to benzodiazepines if https://abs.twimg.com/emoji/v2/... draggable="false" alt="1⃣" title="Tastenkappe Ziffer 1" aria-label="Emoji: Tastenkappe Ziffer 1"> if you have an α and a γ subunit and https://abs.twimg.com/emoji/v2/... draggable="false" alt="2⃣" title="Tastenkappe Ziffer 2" aria-label="Emoji: Tastenkappe Ziffer 2"> if the α subunit is α1, α2, α3, or α5 (not α4 or α6)
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Digging a little deeper, the actions of benzos rely on certain α subunits as well!
Anxiolytics - α2, α3
Sedatives - α1, α5
Anticonvulsants - α1, α2, α3, α5
Anterograde amnesia - α1
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Anxiolytics - α2, α3
Sedatives - α1, α5
Anticonvulsants - α1, α2, α3, α5
Anterograde amnesia - α1
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Why so many subtypes and subunits?
Bodies are great at doing a lot with very little, so having all these combos is a pretty cool way of getting a bunch of different receptors out of one receptor. The receptor types are also distributed differently (see table, from wiki).
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Bodies are great at doing a lot with very little, so having all these combos is a pretty cool way of getting a bunch of different receptors out of one receptor. The receptor types are also distributed differently (see table, from wiki).
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So what happens when a GABA-A receptor& #39;s activated?
The GABA-A receptor is ligand-gated ion channel. Once its ligand (GABA) "opens the gate", chloride ions flow into the cell. Benzos don& #39;t actually activate the receptor; they& #39;re called positive allosteric modulators (PAMs).
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The GABA-A receptor is ligand-gated ion channel. Once its ligand (GABA) "opens the gate", chloride ions flow into the cell. Benzos don& #39;t actually activate the receptor; they& #39;re called positive allosteric modulators (PAMs).
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PAMs are like a wingperson for a ligand. They can increase a receptor& #39;s affinity for a ligand, stabilize an active confirmation, increase the time the channel is open (list is not exhaustive) but can only do this if there is a ligand present.
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So PAMs can do different things!
With the GABA-A receptor, benzoshttps://abs.twimg.com/emoji/v2/... draggable="false" alt="⬆️" title="Pfeil nach oben" aria-label="Emoji: Pfeil nach oben"> the frequency of the channel opening. Barbiturates are also PAMs, but they https://abs.twimg.com/emoji/v2/... draggable="false" alt="⬆️" title="Pfeil nach oben" aria-label="Emoji: Pfeil nach oben"> the duration of the channel opening. In both cases, GABA would need to be present; PAMs can& #39;t act alone https://abs.twimg.com/emoji/v2/... draggable="false" alt="💞" title="Drehende Herzen" aria-label="Emoji: Drehende Herzen">
7/7 #PharmPhriday
With the GABA-A receptor, benzos
7/7 #PharmPhriday
