Central anticonvulsant effects of magnesium sulfate on N-methyl-D-aspartate-induced seizures.
OBJECTIVE
The objective of this study was to determine if magnesium sulfate's central anticonvulsant activity is effective against N-methyl-D-aspartate-induced seizures.


METHODS
In two separate experiments we investigated magnesium sulfate's ability to inhibit N-methyl-D-aspartate-induced hippocampal seizures in rats. In the first experiment magnesium sulfate was administered peripherally before an intracranial injection of 20 micrograms of N-methyl-D-aspartate. In the second experiment magnesium sulfate was injected intracranially concurrently with N-methyl-D-aspartate. The ability of magnesium sulfate to suppress N-methyl-D-aspartate-induced seizure activity under both conditions was assessed.


RESULTS
Peripherally administered magnesium sulfate significantly increased the latency from the time of an N-methyl-D-aspartate injection to the first seizure both by acute injection and after 2 hours of sustained elevation of serum magnesium levels when compared with saline solution-injected controls (p < 0.01). The duration of the first seizure was also significantly reduced. Intracranially administered magnesium sulfate significantly (p < 0.01) increased the seizure latency period by 120%. Overall, central magnesium sulfate prevented seizure activity in 40% of the animals (p < 0.01).


CONCLUSIONS
Magnesium sulfate has a central anticonvulsant action on N-methyl-D-aspartate-induced seizures in this rat model of hippocampal seizures.
Cotton
D B
DB
Department of Obstetrics and Gynecology, Wayne State University/Hutzel Hospital, Detroit, MI 48201.
Hallak
M
M
Janusz
C
C
Irtenkauf
S M
SM
Berman
R F
RF
D000818:Animals; D000927:Anticonvulsants / Q000627:therapeutic use*; D001522:Behavior, Animal / Q000502:physiology; D005260:Female; D007031:Hypothalamus / Q000503:physiopathology; D008278:Magnesium Sulfate / Q000008:administration & dosage / Q000627:therapeutic use*; D016202:N-Methylaspartate / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000139:chemically induced / Q000503:physiopathology / Q000517:prevention & control*
D000927:Anticonvulsants; D016202:N-Methylaspartate; D008278:Magnesium Sulfate