3,4-диаминопиридин

Химические свойства

brownish to brown-grey crystalline powder

Использование

It is a potassium channel blocker in nerve terminals. It inhibits potassium channel efflux, increasing the duration of the action potential, which results in an increase in the duration of calcium channel opening and enhanced acetylcholine (ACh) release. Increased ACh availability at the motor end plate allows muscles to contract.

Показания

3,4-diaminopyridine has been used to treat Lambert Eaton myasthenia (LEM) for thirty years despite the lack of conclusive evidence of efficacy.
Lambert–Eaton myasthenic syndrome is characterized by muscle weakness, hyporeflexia, and autonomic dysfunction, which result from impaired release of acetylcholine from cholinergic nerve terminals. It is frequently associated with cancer, it is autoimmune-mediated, and treatment has been unsatisfactory.
The drug 3,4-diaminopyridine (3,4-DAP) increases neurotransmitter release and also the action potential (by blocking potassium conductance); these actions lead to a nonspecific excitatory effect on the cholinergic system, and provide benefit. It should be taken orally, 4-5 times per day. Adverse effects due to CNS excitation (insomnia, seizures) can occur.

Методы очистки

It crystallises from *benzene and is stored under N2 because it is deliquescent and absorbs CO2. [Beilstein 22/11 V 266.]