Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
9 Cards in this Set
- Front
- Back
Mechanism of Action for Donepezil
|
Donepezil is a specific, noncompetitive, reversible inhibitor of acetylcholinesterase. It exhibits a relatively high degree of selectivity for neuronal AChE, only weakly inhibiting butylcholinesterase or AChE in smooth, striated, or cardiac muscle. It’s tertiary structure facilitates crossing of the BBB.
|
|
Mechanism of Action for Rivastigmine
|
Rivastigmine is a tertiary amine sporting a carbamoyl ester linkage that serves as a substrate for AChE. It reacts to produce an alkylcarbamoyl moiety, reversibly sequestering the enzyme in a more stable form, precluding it from hydrolyzing ACh. It also inhibits butylcholinesterase.
|
|
Mechanism of Action for Galantamine
|
Galantamine is a reversible inhibitor of cholinesterase activity and it also has nicotinic receptor agonist properties.
|
|
Mechanism of Action for Tacrine
|
Inhibits AChE by reversibly binding to the active center. It does so with a higher affinity than does edrophonium and, having primary structure rather than a quaternary one, it is more lipophilic and more readily crosses the BBB.
|
|
Mechanisms of Action for Memantine
|
Memantine preferentially blocks excessive activity of extrasynaptic NMDA receptors largely responsible for neuronal damage contributing to neurodegenerative diseases, such as Alzheimer’s disease.
|
|
Mechanism of Action for Levodopa
|
Levodopa is the immediate metabolic precursor of dopamine and is capable of crossing the BBB via L-amino acid transporter. It is given to increase dopamine levels in the brain to compensate for the loss of the dopamine-generating cells of the substantia nigra associated with Parkinson’s disease.
|
|
Mechanism of Action for Carbidopa
|
Carbidopa is an inhibitor of dopa decarboxylase that is incapable of crossing the BBB. When co-administered with levodopa, it inhibits the decarboxylation of levodopa in the periphery, thus facilitating levadopa’s bioavailability in the CNS.
|
|
Contraindications for Levodopa
|
Levodopa should not be given to patients who are psychotic or patients who have glaucoma. Levodopa + carbidopa should not be given to patients who have cardiac disease. Patients with active peptic ulcers “must be managed with care.” And levodopa is a precursor of skin melanin and thus may activate malignant melanoma. Thus history of melanoma is a relative contraindication.
|
|
Mechanism of Action for Riluzole
|
Presynaptically, riluzole inhibits glutamate release. Postsynaptically, riluzole blocks NMDA- and kainate-type glutamate receptors and "inhibits voltage-dependent channels." Riluzole also significantly increases glutamte uptake.
|