What is a receptor theory of drug action?
A drug receptor is a specialized target macromolecule that binds a drug and mediates its pharmacological action. These receptors may be enzymes, nucleic acids, or specialized membrane-bound proteins. The formation of the drug-receptor complex leads to a biological response.
What is a drug receptor definition?
7.2 Drug receptors. Receptor is a macromolecule in the membrane or inside the cell that specifically (chemically) bind a ligand (drug). The binding of a drug to receptor depends on types of chemical bounds that can be established between drug and receptor.
What do you know about theory of drug receptor interaction explain it?
In summary: Drugs interact with receptors to produce a change in the state of the receptor, which is then translated into a physiological effect. This molecular interaction with the receptor can be modeled mathematically and obeys the Law of Mass Action.
What is the principle of drug receptor interaction?
Molecules (eg, drugs, hormones, neurotransmitters) that bind to a receptor are called ligands. The binding can be specific and reversible. A ligand may activate or inactivate a receptor; activation may increase or decrease a particular cell function. Each ligand may interact with multiple receptor subtypes.
What is the function of the receptor?
Receptors are a special class of proteins that function by binding a specific ligand molecule. When a ligand binds to its receptor, the receptor can change conformation, transmitting a signal into the cell.
What is the theory of drug action?
A theory of drug action is developed on the assumption that excitation by a stimulant drug is proportional to the rate of drug-receptor combination, rather than to the proportion of receptors occupied by the drug.
What is the importance of drug receptor?
The receptor’s affinity for binding a drug determines the concentration of drug required to form a significant number of ligand-receptor complexes, and the total number of receptors may limit the maximal effect a drug may produce. Second, receptors are responsible for selectivity of drug action.
What are the theories of drug actions?
What is rate theory in pharmacology?
Rate Theory: the idea that a response emanates from a receptor in proportion to the kinetic rate of onset and offset of drug binding to the receptor.
What are theories of drug receptors?
Occupation Theory: the idea that a response emanates from a receptor only when it is occupied by an appropriate ligand (drug). Rate Theory: the idea that a response emanates from a receptor in proportion to the kinetic rate of onset and offset of drug binding to the receptor.
What is called receptor?
Receptors Definition Receptors are proteins, usually cell surface receptors, which bind to ligands and cause responses in the immune system, including cytokine receptors, growth factor receptors and Fc receptor. Receptors can induce cell growth, division and death; control membrane channels or regulate cell binding.
What are the types of drug receptors?
Receptors are generally classified into two types: an ion channel type and a coupled type receptor or “G protein”. Nicotine acts at one of the former and morphine at one of the latter. However, sometimes the initial molecular site that a drug acts at is not one of these two classical types of receptors.
What is receptor site theory?
Receptor Site Theory is a widely accepted theory of how the interior of the nose detects different smells.
What is the relationship of the receptors to pharmacodynamics?
The interaction of a drug molecule with a receptor causes the initiation of a sequence of molecular events, resulting in a pharmacodynamic or pharmacologic response. The term pharmacodynamics refers to the relationship between drug concentrations at the site of action (receptor) and pharmacologic response.
What is drug affinity?
drug affinity. the attraction of a particular class of receptor to a drug, at a level sufficient to give an observable reaction. Such a drug is an agonist .