Premium
Lambert–Eaton myasthenic syndrome: mouse passive‐transfer model illuminates disease pathology and facilitates testing therapeutic leads
Author(s) -
Meriney Stephen D.,
Tarr Tyler B.,
Ojala Kristine S.,
Wu Man,
Li Yizhi,
Lacomis David,
GarciaOcaña Adolfo,
Liang Mary,
Valdomir Guillermo,
Wipf Peter
Publication year - 2018
Publication title -
annals of the new york academy of sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.712
H-Index - 248
eISSN - 1749-6632
pISSN - 0077-8923
DOI - 10.1111/nyas.13512
Subject(s) - lambert eaton myasthenic syndrome , neuromuscular junction , neuromuscular transmission , voltage dependent calcium channel , calcium , gating , acetylcholine , congenital myasthenic syndrome , potassium channel , neuroscience , synapse , myasthenia gravis , calcium channel , acetylcholine receptor , chemistry , medicine , pharmacology , endocrinology , biology , receptor
Abstract Lambert–Eaton myasthenic syndrome (LEMS) is an autoimmune disorder caused by antibodies directed against the voltage‐gated calcium channels that provide the calcium ion flux that triggers acetylcholine release at the neuromuscular junction. To study the pathophysiology of LEMS and test candidate therapeutic strategies, a passive‐transfer animal model has been developed in mice, which can be created by daily intraperitoneal injections of LEMS patient serum or IgG into mice for 2–4 weeks. Results from studies of the mouse neuromuscular junction have revealed that each synapse has hundreds of transmitter release sites but that the probability for release at each one is likely to be low. LEMS further reduces this low probability such that transmission is no longer effective at triggering a muscle contraction. The LEMS‐mediated attack reduces the number of presynaptic calcium channels, disorganizes transmitter release sites, and results in the homeostatic upregulation of other calcium channel types. Symptomatic treatment is focused on increasing the probability of release from dysfunctional release sites. Current treatment uses the potassium channel blocker 3,4‐diaminopyridine (DAP) to broaden the presynaptic action potential, providing more time for calcium channels to open. Current research is focused on testing new calcium channel gating modifiers that work synergistically with DAP.