Lec 17 Flashcards
What is defined as “ a process that is generally slow and often involves a receptor molecule that is different than the ion channel that is affected.”
Modulation (a metabotropic or Gprotein coupled action)
What type of receptor is present when the primary receptor is a physically separate molecule that communicates to the channel molecule through 2nd messengers?
metabotropic receptor or Gprotein receptor
Widely divergent networks of neural pathways (one neuron branches to many neurons) are examples of what type of system?
modulatory systems
more general alterations of the brain are controlled by what type of systems? (eg. falling asleep, waking up, attentive)
modulatory systems
Modulatory systems generally use what type of chemical synapse?
metabotropic synapse or receptors
what is it called when an input changes the responsiveness of a cell according to other inputs?
modulation
What is the metabotropic receptor for ACh?
muscarinic receptor
What is the metabotropic receptor for Glutamate?
mGluR
What is the metabotropic receptor for GABA?
GABAb
What is the metabotropic receptor for Glycine?
there isn’t one.
What is the metabotropic receptor for catecholamines?
a1,a2,B,D1,D2
metabotropic receptors for catecholamines are primarily found in what nervous system?
ANS
What is the metabotropic receptor for Anandamide?
Cannabinoid R –> natural ligand in weed can activate
What is the ionotropic receptor for the ligand ACh?
Nicotinic receptor
What is the ionotropic receptor for the ligand Glycine?
NMDA, AMPA (GluR?)
What is the ionotropic receptor for the ligand GABA?
GABAa
What is the ionotropic receptor for catecholamines?
there isn’t one
What is the ionotropic receptor for Anandamide?
there isn’t one
What studied ligands do not have a metabotropic receptor?
Catecholamines and Anandamide
GPCRs generally have how many TM regions?
7 TMs
A classical second messenger cascade:
what happens following the binding of an agonst to the GPCR?
the activated receptor interacts with the aBy heterotrimer to promote a conformational change that facilitates the release of bound GDP and simultaneously binds GTP to alpha subunit.
A classical second messenger cascade:
What happens following the binding of GTP to the a subunit of the Gprotein?
the GDP-GTP exchange stimulates dissociation of the Gprotein complex from the receptor.
A classical second messenger cascade:
What happens follow the dissociation of the Gprotein from its receptor?
disassembly of the trimer into a free alpha subunit and “By” (beta-gamma) subunit
A classical second messenger cascade:
What happens after the disassembly of the trimer?
- The free active GTP-bound alpha subunit can now interact in the plane of the membrane with downstream effectors such as adenylyl cyclase and phospholipases
- and the “By” subunit can now activate ion channels or other effectors