inhibitoija

An inhibitoija, in scientific usage often rendered as inhibitor, is a substance or molecule that reduces the activity of a target, such as an enzyme, receptor, or signaling pathway. Inhibitors may act to slow or completely block a reaction or process. They are central to fields ranging from biochemistry to pharmacology and toxicology.

Mechanisms of inhibition include competitive inhibition, where the inhibitor resembles the substrate and binds to the enzyme's active site; noncompetitive inhibition, where the inhibitor binds to a separate site and alters activity; and uncompetitive inhibition, which occurs when the enzyme–substrate complex binds the inhibitor. Some inhibitors act allosterically or via covalent modification.

Examples include protease inhibitors used in HIV therapy; acetylcholinesterase inhibitors used for glaucoma and Alzheimer's disease; COX inhibitors (NSAIDs) that reduce inflammation; and tyrosine kinase inhibitors used in cancer therapy.

Applications and considerations: In research, inhibitors help map pathways and quantify enzyme kinetics. Clinically, inhibitors form the basis of many drugs but can cause side effects and resistance. In agriculture, herbicides and pesticides often function as inhibitors of plant or insect enzymes.

See also: enzyme inhibition, receptor antagonists, allosteric regulation, pharmacology.