Abstract |
Recent brain research proposes that, during ischemia, synaptically released excitatory amino acid neurotransmitters accumulate at toxic concentrations with ensuing neuronal death. Their action is mediated by the receptor subtype N-methyl-D-aspartate ( NMDA). The protective effect of NMDA receptor blockade with intrathecal MgSO4 and MK-801 was investigated during spinal cord ischemia induced by aortic occlusion of 12 minutes. Male Sprague-Dawley rats, 250-300g, underwent intrathecal administration of 20 microL of normal saline (SA n = 16), MgSO4 1M (MG n = 16), or MK-801, 25 mM solutions (MK n = 16) in a randomized order. After 2 hours, the animals underwent occlusion of the thoracic aorta and subclavian arteries for 12 min. An additional control group (CO n = 16) underwent occlusion for 12 minutes, without intrathecal injection. The animals were scored according to their functional performance (LS = lesion score) each day for four days by a blinded observer. Mean LS were calculated for each group at a given day. Treatment and control groups were not different at day 1 (P = 0.302). Group MG was improved from groups SA (P = < 0.0039) and CO (P = < 0.0048) at day 4. This study demonstrates that although intrathecal NMDA receptor blockade with MgSO4 or MK-801 does not prevent paraplegia due to spinal cord ischemia in the rat, it could however influence the rate of recovery after ischemic injury.
|
Authors | F Follis, K Miller, O U Scremin, S Pett, R Kessler, J Wernly |
Journal | The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques
(Can J Neurol Sci)
Vol. 21
Issue 3
Pg. 227-32
(Aug 1994)
ISSN: 0317-1671 [Print] England |
PMID | 8000978
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
|
Chemical References |
- Receptors, N-Methyl-D-Aspartate
- Dizocilpine Maleate
- Magnesium Sulfate
|
Topics |
- Animals
- Aorta, Thoracic
- Constriction
- Disease Models, Animal
- Dizocilpine Maleate
(administration & dosage, pharmacology)
- Injections, Spinal
- Ischemia
(pathology)
- Magnesium Sulfate
(administration & dosage, pharmacology)
- Male
- Neurologic Examination
- Pilot Projects
- Rats
- Rats, Sprague-Dawley
- Receptors, N-Methyl-D-Aspartate
(antagonists & inhibitors)
- Regional Blood Flow
- Spinal Cord
(blood supply, pathology)
|