Doors 32 Documentation. Our longstanding and much loved Doors32 Software is now available only via download from Keri's web site or special order, but is still free of charge. It will continue to be available as long as customers ask for it and computers with compatible operating systems exist.
Cell biology The reduction of a cellâs response to a hormone or other ligand by internalizing its cognate receptor and degrading it within a coated pit; downregulation is a mechanism by which receptors respond to an excess of ligands.
As ionotropic receptors, nAChRs are directly linked to ion channels and do not use second messengers (as metabotropic receptors do). Nicotinic acetylcholine receptors are the best-studied of the ionotropic receptors.Like the other type of acetylcholine receptor âthe muscarinic acetylcholine receptor (mAChR)âthe nAChR is triggered by the binding of the neurotransmitter acetylcholine (ACh).s ionotropic receptors, nAChRs are directly linked to ion channels and do not use second messengers (as metabotropic receptors do). Nicotinic acetylcholine receptors are the best-studied of the ionotropic receptors.