Drug Action

Enzymes and Drug Action

Neurochemistry of drug action

Proton magnetic resonance spectroscopy (H MRS) is a noninvasive imaging technique that permits measurement of particular compounds or metabolites within the tissue of interest. In the brain, H MRS provides a snapshot of the neurochemical environment within a defined volume of interest. A search of the literature demonstrates the widespread utility of this technique for characterizing tumors, tr...

UFT: mechanism of drug action.

The mechanism of action of fluorouracil (5-FU) and the oral fluoropyrimidines and the importance of biochemical modulation and inhibition of dihydropyrimidine dehydrogenase for oral application of the prodrugs of 5-FU are discussed. The regulation of thymidylate synthase, as well as its roles as a target for antineoplastic activity and in drug resistance, are also mentioned. The more downstream...

Antiepileptic drug mechanisms of action.

Established antiepileptic drugs (AEDs) decrease membrane excitability by interacting with neurotransmitter receptors or ion channels. AEDs developed before 1980 appear to act on sodium channels, gamma-aminobutyric acid type A (GABAA) receptors, or calcium channels. Benzodiazepines and barbiturates enhance GABAA receptor-mediated inhibition. Phenytoin (PHT), carbamazepine (CBZ), and possibly val...

A Primer of Drug Action

problems of emphasis rather than fact exist. The advantages of enteral over parenteral nutritional support are mentioned only as cursory notes. In addition to protection from atrophy of the GI tract, the lower costs of enteral support mandate its use whenever possible. Similarly, the weighty ethical issues involved in hyperalimentation of the terminally ill patient are only briefly mentioned in...