Biomaterial Database

Facilitatory effects of 4-aminopyridine on strontium-mediated evoked and delayed transmitter release from motor nerve terminals. 1982

J Molgó, and M Lemeignan, and S Guerrero

The effect of 4-aminopyridine (4-AP) on Sr-mediated evoked and delayed transmitter release at the frog neuromuscular junction was examined using conventional electrophysiological techniques. 4-AP (5-50 microM) increased transmitter release evoked in response to conducted nerve impulses or to electrotonic depolarization of tetrodotoxin (TTX)-treated motor nerve terminals. Spontaneous quantal transmitter release was not affected by the drug as judged by the lack of effect on miniature end-plate potentials (MEPPs) frequency. However, 4-AP (10-20 microM) markedly enhanced the frequency of MEPPs appearing during conducted low rate repetitive nerve impulses or single electrotonic depolarization of TTX-blocked nerve terminals. The results suggest that 4-AP increases the influx of Sr2+ into nerve terminals in a way that modifies its sequestration and removal by the subcellular elements of the terminal.

UI	MeSH Term	Description	Entries
D009046	Motor Neurons	Neurons which activate MUSCLE CELLS.	Neurons, Motor,Alpha Motorneurons,Motoneurons,Motor Neurons, Alpha,Neurons, Alpha Motor,Alpha Motor Neuron,Alpha Motor Neurons,Alpha Motorneuron,Motoneuron,Motor Neuron,Motor Neuron, Alpha,Motorneuron, Alpha,Motorneurons, Alpha,Neuron, Alpha Motor,Neuron, Motor
D009411	Nerve Endings	Branch-like terminations of NERVE FIBERS, sensory or motor NEURONS. Endings of sensory neurons are the beginnings of afferent pathway to the CENTRAL NERVOUS SYSTEM. Endings of motor neurons are the terminals of axons at the muscle cells. Nerve endings which release neurotransmitters are called PRESYNAPTIC TERMINALS.	Ending, Nerve,Endings, Nerve,Nerve Ending
D011893	Rana esculenta	An edible species of the family Ranidae, occurring in Europe and used extensively in biomedical research. Commonly referred to as "edible frog".	Pelophylax esculentus
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D000631	Aminopyridines	Pyridines substituted in any position with an amino group. May be hydrogenated but must retain at least one double bond.	Aminopyridine
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001001	Anura	An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.	Bombina,Frogs and Toads,Salientia,Toad, Fire-Bellied,Toads and Frogs,Anuras,Fire-Bellied Toad,Fire-Bellied Toads,Salientias,Toad, Fire Bellied,Toads, Fire-Bellied
D013324	Strontium	An element of the alkaline earth family of metals. It has the atomic symbol Sr, atomic number 38, and atomic weight 87.62.
D013779	Tetrodotoxin	An aminoperhydroquinazoline poison found mainly in the liver and ovaries of fishes in the order TETRAODONTIFORMES, which are eaten. The toxin causes paresthesia and paralysis through interference with neuromuscular conduction.	Fugu Toxin,Tarichatoxin,Tetradotoxin,Toxin, Fugu
D015761	4-Aminopyridine	One of the POTASSIUM CHANNEL BLOCKERS with secondary effect on calcium currents which is used mainly as a research tool and to characterize channel subtypes.	4-Aminopyridine Sustained Release,Dalfampridine,Fampridine-SR,Pymadine,VMI-103,4 Aminopyridine,4 Aminopyridine Sustained Release,Fampridine SR,Sustained Release, 4-Aminopyridine,VMI 103,VMI103