alkylating agent

agent (a´jent) something capable of producing an effect.

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adrenergic blocking agent  one that inhibits response to sympathetic impulses by blocking the alpha (alpha-adrenergic blocking a.) or beta (beta-adrenergic blocking a.) receptor sites of effector organs.

adrenergic neuron blocking agent  one that inhibits the release of norepinephrine from postganglionic adrenergic nerve endings.

alkylating agent  a cytotoxic agent, e.g., a nitrogen mustard, which is highly reactive and can donate an alkyl group to another compound. Alkylating agents inhibit cell division by reacting with DNA and are used as antineoplastic agents.

blocking agent  an agent that inhibits a biological action, such as movement of an ion across the cell membrane, passage of a neural impulse, or interaction with a specific receptor.

calcium channel blocking agent  any of a class of drugs that inhibit the influx of calcium ions across the cell membrane or inhibit the mobilization of calcium from intracellular stores; used in the treatment of angina, cardiac arrhythmias, and hypertension.

chelating agent 

1. a compound that combines with metal ions to form stable ring structures.

2. a substance used to reduce the concentration of free metal ion in solution by complexing it.

cholinergic blocking agent  one that blocks or inactivates acetylcholine.

emulsifying agent  emulsifier.

ganglionic blocking agent  one that blocks nerve impulses at autonomic ganglionic synapses.

inotropic agent  any of a class of agents affecting the force of muscle contraction, particularly a drug affecting the force of cardiac contraction; positive inotropic agents increase, and negative inotropic agents decrease the force of cardiac muscle contraction.

luting agent  lute (1).

neuromuscular blocking agent  a compound that causes paralysis of skeletal muscle by blocking neural transmission at the neuromuscular junction.

nonsteroidal antiinflammatory agent  see under drug.

Agent Orange  a herbicide containing 2,4,5-T and 2,4-D and the contaminant dioxin; it is suspected of being carcinogenic and teratogenic.

oxidizing agent  a substance capable of accepting electrons from another substance, thereby oxidizing the second substance and itself becoming reduced.

potassium channel blocking agent  any of a class of antiarrhythmic agents that inhibit the movement of potassium ions through the potassium channels, thus prolonging repolarization of the cell membrane.

progestational agent  progestin: any of a group of hormones secreted by the corpus luteum and placenta and, in small amounts, by the adrenal cortex, including progesterone; they induce the formation of a secretory endometrium. Agents having progestational activity are also produced synthetically.

psychoactive agent , psychotropic agent psychoactive substance.

reducing agent  a substance that acts as an electron donor in a chemical redox reaction.

sclerosing agent  sclerosant; a chemical irritant injected into a vein in sclerotherapy.

sodium channel blocking agent  any of a class of antiarrhythmic agents that prevent ectopic beats by acting on partially inactivated sodium channels to inhibit abnormal depolarizations.

surface-active agent  a substance that exerts a change on the surface properties of a liquid, especially one that reduces its surface tension, as a detergent.

wetting agent  a substance that lowers the surface tension of water to promote wetting.

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al·kyl·at·ing agent (lk-ltng)

n.

Any of various highly reactive chemical compounds that bond with various nucleophilic groups in nucleic acids and proteins and cause mutagenic, carcinogenic, or cytotoxic effects.

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Alkylating agent

A chemical that alters the composition of the genetic material of rapidly dividing cells, such as cancer cells, causing selective cell death; used as a topical chemotherapeutic agent to treat CTCL.

Mentioned in: Alemtuzumab, Cutaneous T-Cell Lymphoma

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alkylating agent

[al′kilā′ting]

any substance that contains an alkyl radical and is capable of replacing a free hydrogen atom in an organic compound, or one that acts by a similar mechanism. This type of chemical reaction results in interference with DNA synthesis and RNA transcription, which in turn results in interference with mitosis and cell division, especially in rapidly proliferating tissue, causing cell death. Alkylating agents are radiometric in that their action is similar to that of irradiation. The agents are useful in the treatment of cancer and are a common class of chemotherapy agents. Agents include cyclophosphamide, mechlorethamine, thiotepa, busulfan, carmustine, lomustine, streptozocin altretamine, and procarbazine. Adverse effects include myleosuppression, particularly anemia and nausea, vomiting, and alopecia.

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alkylating agent

a compound containing alkyl groups that combine readily with other molecules. Their action seems to be chiefly on the deoxyribonucleic acid (DNA) in the nucleus of the cell. They are used in chemotherapy of cancer although they do not damage malignant cells selectively, but also have a toxic action on normal cells. Locally they cause blistering of the skin and damage to the eyes and respiratory tract. Systemic toxic effects are nausea and vomiting, reduction in both leukocytes and erythrocytes, and hemorrhagic tendencies. Among the agents of this group used in therapy are the nitrogen mustards, including mechlorethamine hydrochloride and chlorambucil, and busulfan and cyclophosphamide.

Also used for the inactivation of organisms in the preparation of vaccines as it does not significantly interfere with antigenicity. β-propiolactone is an example.

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alkylating agent

Molecular biology An organic compound able to transfer an alkyl group to a nucleotide Oncology A generic term for any of a family of chemotherapeutics that cause irreversible damage to tumor cells and apoptotic destruction Route of administration IV, oral Adverse reactions Stomatitis, N&V, diarrhea, skin rash, anemia, alopecia; with cyclophosphamide, hemorrhagic cystitis, cardiac toxicity. Cf Antimetabolite, Plant alkaloid, Topoisomerase inhibitor.