4-Aminopyridine
2194910
217881208
2008-06-08T03:23:26Z
68.9.121.52
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{{Chembox new
|ImageFile=4-aminopyridine.png
|ImageSize=80px
|IUPACName=pyridin-4-amine
|OtherNames=4-pyridinamine, 4-Pyridylamine, Fampridine
|Section1= {{Chembox Identifiers
| CASNo=504-24-5
| PubChem=1727
| SMILES=C1=CN=CC=C1N
| MeSHName=4-Aminopyridine
}}
|Section2= {{Chembox Properties
| Formula=C<sub>5</sub>H<sub>6</sub>N<sub>2</sub>
| MolarMass=94.1146
| Appearance=colourless solid
| Density=
| MeltingPt=155-158 °C
| BoilingPt=273 °C
| Solubility= polar organic solvents
}}
|Section3= {{Chembox Hazards
| MainHazards=
| FlashPt=
| Autoignition=
}}
}}
'''4-Aminopyridine''' is an [[organic compound]] with the [[Chemical formula|formula]] H<sub>2</sub>NC<sub>5</sub>H<sub>4</sub>N. The molecule is one of the three isomeric [[amine]]s of [[pyridine]]. It is used primarily as a research tool and is helpful in characterizing subtypes of [[potassium channel]].
==Production==
4-Aminopyridine is prepared by the decarbonylation of pyridine-4-carboxyamide.<ref>Shinkichi Shimizu, Nanao Watanabe, Toshiaki Kataoka, Takayuki Shoji, Nobuyuki Abe, Sinji Morishita, Hisao Ichimura "Pyridine and Pyridine Derivatives" in "Ullmann's Encyclopedia of Industrial Chemistry" 2007; John Wiley & Sons: New York.</ref>
==Pharmaceutical applications==
It has been used clinically in [[Lambert-Eaton myasthenic syndrome]] and [[multiple sclerosis]] because by blocking potassium channels it prolongs [[action potentials]] thereby increasing transmitter release at the [[neuromuscular junction]] and elsewhere.<ref>{{cite journal |author=Judge S, Bever C |title=Potassium channel blockers in multiple sclerosis: neuronal Kv channels and effects of symptomatic treatment |journal=Pharmacol. Ther. |volume=111 |issue=1 |pages=224–59 |year=2006 |pmid=16472864 |doi=10.1016/j.pharmthera.2005.10.006}}</ref> The drug Pinacidil is a derivative of 4-aminopyridine that is also used as a potassium channel opener.
The drug, known as Neurelan, has been shown to reverse [[tetrodotoxin]] toxicity in animal experiments.<ref>[http://www.emedicine.com/emerg/topic342.htm Octopus Envenomations] at eMedicine.com</ref>
It is also marketed as Fampridine by [[Acorda]] for the treatment of multiple sclerosis, for which it is now in [[Clinical trial|Phase II clinical trials]].
4-Aminopyridine is marketed as an avicide under the trade name Avitrol. In this treatment it causes convulsions and rarely death, depending on dosage.
==Multiple Sclerosis==
4-Aminopyridine (4-AP) is a drug shown to improve visual function and motor skills and relieve fatigue in patients with [[Multiple Sclerosis]] (MS). 4-AP is most effective in patients with the chronic progressive form of MS, in patients who are temperature sensitive, and in patients who have had MS for longer than three years. Common side effects include dizziness, nervousness and nausea, and the incidence of adverse effects was shown to be less than 5% in all studies.
4-AP works as a potassium channel blocker. Electrophysiologic studies of demyelinated axons show that abnormal potassium currents decrease action potential duration and amplitude and contribute to conduction failure. Potassium channel blockade prolongs the depolarization phase of the action potential, increasing conductivity along the demyelinated axon.
MS patients treated with 4-AP exhibited a response rate of 29.5% to 80%. A long-term study (32 months) indicated that 80-90% of patients who initially responded to 4-AP exhibited long-term benefits. Although improving symptoms, 4-AP does not inhibit progression of MS.
Spinal cord injury patients have also seen improvement with 4-AP therapy. These improvements include sensory, motor and pulmonary function, with a decrease in spasticity and pain.<ref>{{cite journal |author=Van Diemen HA, Polman CH, Koetsier JC, Van Loenen AC, Nauta JJ, Bertelsmann FW |title=4-Aminopyridine in patients with multiple sclerosis: dosage and serum level related to efficacy and safety |journal=Clinical Neuropharmacology |volume=16 |issue=3 |pages=195–204 |year=1993 |pmid=8504436}}</ref>.
==Overdose==
Conditions associated with overdose have included [[parasthesia]]s and [[seizure]]s.<ref>{{cite journal |author=Pickett T, Enns R |title=Atypical presentation of 4-aminopyridine overdose |journal=Annals of emergency medicine |volume=27 |issue=3 |pages=382–5 |year=1996 |pmid=8599505 |doi=10.1016/S0196-0644(96)70277-9}}</ref>, and [[atrial fibrillation]].<ref>{{cite journal |author=Johnson N, Morgan M |title=An unusual case of 4-aminopyridine toxicity |journal=The Journal of emergency medicine |volume=30 |issue=2 |pages=175–7 |year=2006 |pmid=16567254 |doi=10.1016/j.jemermed.2005.04.020}}</ref>
==See also==
*[[4-Dimethylaminopyridine]]
*[[pyridine]]
==References==
<references/>
==External links==
http://www.avitrol.com/GrainFAQ/index.php
{{DEFAULTSORT:Aminopyridine, 4-}}
[[Category:Pyridines]]
[[Category:Amines]]
{{amine-stub}}