Lamotrigine and retigabine increase motor threshold in transcranial magnetic stimulation at the dose required to produce an antiepileptic effect against maximal electroshock-induced seizure in rats.

Abstract	Transcranial magnetic stimulation (TMS) is a neurophysiological technique that enables noninvasive evaluation of neuronal excitability in the brain. In the past, a large number of antiepileptic drugs were shown to increase the motor threshold (MT) in clinical TMS studies, suggesting the inhibition of excessive neuronal excitability. To facilitate drug development, the confirmation of similar changes in neurophysiological biomarkers in both preclinical and clinical studies is crucial; however, until now, there have been no data showing the drug efficacies on neuronal excitabilities as measured using TMS in rodents. In this study, we found that the antiepileptic drugs, lamotrigine (10 mg/kg) and retigabine (5 mg/kg), significantly increased the MT in rats using TMS, which is similar to clinical study findings. In addition, we demonstrated that these drugs could inhibit maximal electroshock (MES)-induced seizures in rats when given at the same dose required to be effective in the TMS experiment. These findings suggest that the effects of antiepileptic drugs in our rat TMS system have a similar sensitivity to that of the antiepileptic effects in rats with MES-induced seizures. The measurement of MT in a TMS study may be a noninvasive translational approach for predicting antiepileptic efficacy in drug development.
Authors	Natsu Hotta, Maki Miyamoto, Kazunori Suzuki
Journal	Neuroscience letters (Neurosci Lett) Vol. 771 Pg. 136460 (02 06 2022) ISSN: 1872-7972 [Electronic] Ireland
PMID	35051437 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Copyright	Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.
Chemical References	Anticonvulsants Carbamates Phenylenediamines ezogabine Lamotrigine
Topics	Animals Anticonvulsants (therapeutic use) Carbamates (therapeutic use) Electroshock (adverse effects) Evoked Potentials, Motor Lamotrigine (therapeutic use) Male Phenylenediamines (therapeutic use) Rats Rats, Sprague-Dawley Seizures (drug therapy, etiology) Transcranial Magnetic Stimulation

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.

Realize the full power of the drug-disease research graph!