A chemical that increases or decreases the strength of the signal a receptor sends into the cell.
A chemical that increases or decreases the strength of the signal a receptor sends into the cell. Allosteric modulators affect constitutive activity and agonists, but their effect will not necessarily be the same for all agonists of a receptor.
Summary from Wikipedia:
In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a receptor to change that receptor's response to stimulus. Some of them, like benzodiazepines, are drugs. The site that an allosteric modulator binds to (i.e., an allosteric site) is not the same one to which an endogenous agonist of the receptor would bind (i.e., an orthosteric site). Modulators and agonists can both be called receptor ligands.
Modulators are either positive, negative or neutral. Positive types increase the response of the receptor by either increasing the probability that an agonist will bind to a receptor (i.e. affinity), or increasing its ability to activate the receptor (i.e. efficacy), or both. Negative types decrease the agonist affinity and/or efficacy. Neutral types don't affect agonist activity, but can stop other modulators from binding to an allosteric site. Some modulators also work as allosteric agonists.
The term "allosteric" derives from the Greek language. Allos means "other", and stereos, "solid" or "shape". This can be translated to "other shape", which indicates the conformational changes within receptors caused by the modulators through which the modulators affect the receptor function.Read more