Magnesium sulfate reduces seizures induced by central administration of the excitatory amino acid n-methyl-d-aspartate in rats

Cynthia A Standley, Susan M. Irtenkauf, Brian A. Mason, William J. Kupsky, David B. Cotton

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

A'-Methyl-D-aspartate (NMDA) has been implicated in a number of pathophysiologic conditions, including seizures. Magnesium is a physiologic blocker of the NMDA receptor. As magnesium sulfate (MgSO4) is currently used as a treatment for eclamptic seizures in North America, we examined the anticonvulsant effects of MgSO4 on central NMDA-induced seizures. Forty-one female rats were surgically anesthetized and a bipolar recording electrode was stereotaxically implanted into the dorsal hippocampus, while a cannula was implanted into the lateral cerebral ventricle for drug injection. Following 1-week recovery, baseline behavior and electrical activity were recorded. Two treatment protocols were examined: (a) chronic-intraperitoneal injection of 270 mg/kg MgSO4, followed every 20 min with 27 mg/kg MgSO4 for a total of 2 h; and (b) acute-intravenous injection of MgSO4 (30, 60, or 90 mg/kg) in a volume of 1.5 mL/kg via the tail vein. Following either treatment protocol, rats received 1 μ;L of 20 mg/mL NMDA via the cannula, and seizure activity was assessed. Onset to the first seizure was significantly lengthened in rats receiving both chronic (P < 0.01) and acute (P < 0.01) MgS04. Total seizure number was significantly reduced in the chronic MgSO4 group (P < 0.05). Total seizure duration was significantly reduced in both the chronic (P < 0.05) and acute (P < 0.05) MgSO4 groups. Mortality was 30% in the chronic control group, whereas none of the rats that received chronic MgSO4 died. We conclude that magnesium sulfate reduces seizure activity induced by centrally administered NMDA. These results support our previous observations that magnesium does have central anticonvulsant effects.

Original languageEnglish (US)
Pages (from-to)235-244
Number of pages10
JournalHypertension in Pregnancy
Volume14
Issue number2
DOIs
StatePublished - 1995
Externally publishedYes

Fingerprint

Magnesium Sulfate
Excitatory Amino Acids
Aspartic Acid
Seizures
N-Methylaspartate
Clinical Protocols
Anticonvulsants
Magnesium
D-Aspartic Acid
Cerebral Ventricles
Lateral Ventricles
North America
N-Methyl-D-Aspartate Receptors
Intraperitoneal Injections
Intravenous Injections
Tail
Veins
Hippocampus
Electrodes
Control Groups

Keywords

  • Eclampsia
  • Excitatory amino acids
  • Magnesium
  • Seizures

ASJC Scopus subject areas

  • Internal Medicine
  • Obstetrics and Gynecology

Cite this

Magnesium sulfate reduces seizures induced by central administration of the excitatory amino acid n-methyl-d-aspartate in rats. / Standley, Cynthia A; Irtenkauf, Susan M.; Mason, Brian A.; Kupsky, William J.; Cotton, David B.

In: Hypertension in Pregnancy, Vol. 14, No. 2, 1995, p. 235-244.

Research output: Contribution to journalArticle

Standley, Cynthia A ; Irtenkauf, Susan M. ; Mason, Brian A. ; Kupsky, William J. ; Cotton, David B. / Magnesium sulfate reduces seizures induced by central administration of the excitatory amino acid n-methyl-d-aspartate in rats. In: Hypertension in Pregnancy. 1995 ; Vol. 14, No. 2. pp. 235-244.
@article{54ab1bf5ba4f4476ae83ac63472dfe2d,
title = "Magnesium sulfate reduces seizures induced by central administration of the excitatory amino acid n-methyl-d-aspartate in rats",
abstract = "A'-Methyl-D-aspartate (NMDA) has been implicated in a number of pathophysiologic conditions, including seizures. Magnesium is a physiologic blocker of the NMDA receptor. As magnesium sulfate (MgSO4) is currently used as a treatment for eclamptic seizures in North America, we examined the anticonvulsant effects of MgSO4 on central NMDA-induced seizures. Forty-one female rats were surgically anesthetized and a bipolar recording electrode was stereotaxically implanted into the dorsal hippocampus, while a cannula was implanted into the lateral cerebral ventricle for drug injection. Following 1-week recovery, baseline behavior and electrical activity were recorded. Two treatment protocols were examined: (a) chronic-intraperitoneal injection of 270 mg/kg MgSO4, followed every 20 min with 27 mg/kg MgSO4 for a total of 2 h; and (b) acute-intravenous injection of MgSO4 (30, 60, or 90 mg/kg) in a volume of 1.5 mL/kg via the tail vein. Following either treatment protocol, rats received 1 μ;L of 20 mg/mL NMDA via the cannula, and seizure activity was assessed. Onset to the first seizure was significantly lengthened in rats receiving both chronic (P < 0.01) and acute (P < 0.01) MgS04. Total seizure number was significantly reduced in the chronic MgSO4 group (P < 0.05). Total seizure duration was significantly reduced in both the chronic (P < 0.05) and acute (P < 0.05) MgSO4 groups. Mortality was 30{\%} in the chronic control group, whereas none of the rats that received chronic MgSO4 died. We conclude that magnesium sulfate reduces seizure activity induced by centrally administered NMDA. These results support our previous observations that magnesium does have central anticonvulsant effects.",
keywords = "Eclampsia, Excitatory amino acids, Magnesium, Seizures",
author = "Standley, {Cynthia A} and Irtenkauf, {Susan M.} and Mason, {Brian A.} and Kupsky, {William J.} and Cotton, {David B.}",
year = "1995",
doi = "10.3109/10641959509009584",
language = "English (US)",
volume = "14",
pages = "235--244",
journal = "Hypertension in Pregnancy",
issn = "1064-1955",
publisher = "Informa Healthcare",
number = "2",

}

TY - JOUR

T1 - Magnesium sulfate reduces seizures induced by central administration of the excitatory amino acid n-methyl-d-aspartate in rats

AU - Standley, Cynthia A

AU - Irtenkauf, Susan M.

AU - Mason, Brian A.

AU - Kupsky, William J.

AU - Cotton, David B.

PY - 1995

Y1 - 1995

N2 - A'-Methyl-D-aspartate (NMDA) has been implicated in a number of pathophysiologic conditions, including seizures. Magnesium is a physiologic blocker of the NMDA receptor. As magnesium sulfate (MgSO4) is currently used as a treatment for eclamptic seizures in North America, we examined the anticonvulsant effects of MgSO4 on central NMDA-induced seizures. Forty-one female rats were surgically anesthetized and a bipolar recording electrode was stereotaxically implanted into the dorsal hippocampus, while a cannula was implanted into the lateral cerebral ventricle for drug injection. Following 1-week recovery, baseline behavior and electrical activity were recorded. Two treatment protocols were examined: (a) chronic-intraperitoneal injection of 270 mg/kg MgSO4, followed every 20 min with 27 mg/kg MgSO4 for a total of 2 h; and (b) acute-intravenous injection of MgSO4 (30, 60, or 90 mg/kg) in a volume of 1.5 mL/kg via the tail vein. Following either treatment protocol, rats received 1 μ;L of 20 mg/mL NMDA via the cannula, and seizure activity was assessed. Onset to the first seizure was significantly lengthened in rats receiving both chronic (P < 0.01) and acute (P < 0.01) MgS04. Total seizure number was significantly reduced in the chronic MgSO4 group (P < 0.05). Total seizure duration was significantly reduced in both the chronic (P < 0.05) and acute (P < 0.05) MgSO4 groups. Mortality was 30% in the chronic control group, whereas none of the rats that received chronic MgSO4 died. We conclude that magnesium sulfate reduces seizure activity induced by centrally administered NMDA. These results support our previous observations that magnesium does have central anticonvulsant effects.

AB - A'-Methyl-D-aspartate (NMDA) has been implicated in a number of pathophysiologic conditions, including seizures. Magnesium is a physiologic blocker of the NMDA receptor. As magnesium sulfate (MgSO4) is currently used as a treatment for eclamptic seizures in North America, we examined the anticonvulsant effects of MgSO4 on central NMDA-induced seizures. Forty-one female rats were surgically anesthetized and a bipolar recording electrode was stereotaxically implanted into the dorsal hippocampus, while a cannula was implanted into the lateral cerebral ventricle for drug injection. Following 1-week recovery, baseline behavior and electrical activity were recorded. Two treatment protocols were examined: (a) chronic-intraperitoneal injection of 270 mg/kg MgSO4, followed every 20 min with 27 mg/kg MgSO4 for a total of 2 h; and (b) acute-intravenous injection of MgSO4 (30, 60, or 90 mg/kg) in a volume of 1.5 mL/kg via the tail vein. Following either treatment protocol, rats received 1 μ;L of 20 mg/mL NMDA via the cannula, and seizure activity was assessed. Onset to the first seizure was significantly lengthened in rats receiving both chronic (P < 0.01) and acute (P < 0.01) MgS04. Total seizure number was significantly reduced in the chronic MgSO4 group (P < 0.05). Total seizure duration was significantly reduced in both the chronic (P < 0.05) and acute (P < 0.05) MgSO4 groups. Mortality was 30% in the chronic control group, whereas none of the rats that received chronic MgSO4 died. We conclude that magnesium sulfate reduces seizure activity induced by centrally administered NMDA. These results support our previous observations that magnesium does have central anticonvulsant effects.

KW - Eclampsia

KW - Excitatory amino acids

KW - Magnesium

KW - Seizures

UR - http://www.scopus.com/inward/record.url?scp=0029039141&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029039141&partnerID=8YFLogxK

U2 - 10.3109/10641959509009584

DO - 10.3109/10641959509009584

M3 - Article

AN - SCOPUS:0029039141

VL - 14

SP - 235

EP - 244

JO - Hypertension in Pregnancy

JF - Hypertension in Pregnancy

SN - 1064-1955

IS - 2

ER -