Search results
Results from the WOW.Com Content Network
The binding of a ligand to the receptor causes a conformation change in the receptor. This conformation change can affect the activity of the receptor and result in the production of active second messengers. [citation needed] In the case of G protein-coupled receptors, the conformation change exposes a binding site for a G-protein.
The muscarinic acetylcholine receptor M 2, also known as the cholinergic receptor, muscarinic 2, is a muscarinic acetylcholine receptor that in humans is encoded by the CHRM2 gene. [5] Multiple alternatively spliced transcript variants have been described for this gene. [5] It is G i-coupled, reducing intracellular levels of cAMP.
M 1, M 3, M 5 receptors are coupled with G q proteins, while M 2 and M 4 receptors are coupled with G i/o proteins. [5] There are other classification systems. For example, the drug pirenzepine is a muscarinic antagonist (decreases the effect of ACh), which is much more potent at M 1 receptors than it is at other subtypes.
Calcium is a ubiquitous second messenger with wide-ranging physiological roles. [2] These include muscle contraction , neuronal transmission (as in an excitatory synapse ), cellular motility (including the movement of flagella and cilia ), fertilization , cell growth (proliferation), neurogenesis , learning and memory as with synaptic ...
G protein-coupled receptors are all metabotropic receptors. When a ligand binds to a G protein-coupled receptor, a guanine nucleotide-binding protein, or G protein, activates a second messenger cascade which can alter gene transcription, regulate other proteins in the cell, release intracellular Ca 2+, or directly affect ion channels on the ...
cAMP-dependent pathway is necessary for many living organisms and life processes. Many different cell responses are mediated by cAMP; these include increase in heart rate, cortisol secretion, and breakdown of glycogen and fat. cAMP is essential for the maintenance of memory in the brain, relaxation in the heart, and water absorbed in the kidney ...
How the ‘second heart’ works. Every time the calf muscle contracts, one-way valves inside the leg veins open and blood gets pushed upwards towards the heart; when the calf muscle relaxes, the ...
The β receptor couples to G s and increases intracellular cAMP activity, resulting in e.g. heart muscle contraction, smooth muscle relaxation and glycogenolysis. There are two main groups of adrenoreceptors, α and β, with 9 subtypes in total: α receptors are subdivided into α 1 (a G q coupled receptor) and α 2 (a G i coupled receptor) [7]