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M J McLean

Publications and source records attributed to M J McLean.

78 records · Page 5Linked to original sources
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A static magnetic field modulates severity of audiogenic seizures and anticonvulsant effects of phenytoin in DBA/2 mice.

RATIONALE: In a search for potential supplements or alternatives to the pharmacological treatment of epilepsy, we examined the effects of static magnetic fields on audiogenic seizures of DBA/2 mice. METHODS: Two strains of DBA/2 mice were subjected to auditory stimulation that resulted sequentially in wild running, loss of righting, clonus, tonic hindlimb extension, and death in 80-95% of animals in different experiments. The incidence of seizure stages in groups of animals pretreated with a static magnetic field, phenytoin (PHT) or both was compared to the incidence in sham-exposed control mice. RESULTS: Depending on magnetic flux density and duration of exposure to the field, seizure severity decreased significantly, but not completely, in both strains. However, incidence of five seizure stages was reduced in one strain, with about half of the mice seizure free. Two seizure stages (tonic hindlimb extension and death) were reduced significantly in the other. Magnetic field pretreatment potentiated the effect of PHT. Clonic seizures refractory to PHT or magnetic field pretreatment in DBA/2J mice responded to pretreatment with a combination of PHT and the magnetic field. CONCLUSIONS: A static magnetic field had some anticonvulsant effects when employed alone. More robust effects were seen in combination with PHT. Further testing of magnetic fields for anticonvulsant effects and elucidation of mechanisms of action seem to be warranted.

Acoustic Stimulation↗
PubMedDate not supplied

In vitro electrophysiological evidence predicting anticonvulsant efficacy of memantine and flunarizine.

Electrophysiological assays on mammalian central neurons in monolayer dissociated cell culture allow classification of clinically used anticonvulsant drugs on a mechanistic basis and predict their clinical spectrum of anticonvulsant efficacy consistently in comparison with data from animal models. Clinical anticonvulsant efficacy of memantine and flunarizine against tonic-donic and partial seizures is predicted on the basis of ability to limit sustained high efficacy frequency repetitive firing of sodium-dependent action potentials and to suppress depolarizing burst firing of neocortical, hippocampal and spinal cord neurons in cell culture. Effects on voltage-sensitive sodium channels, and possibly potassium channels, may explain, at least in part, the mechanism of anticonvulsant efficacy of memantine and flunarizine.

Amantadine↗