The changes of spinal blood flow and neurotransmitters after experimental spinal cord injury in rabbits.

点击翻译按钮获取中文摘要

The changes in spinal micro circulation and the effects of endogenous excitatory amino acid on the pathogenic mechanism of paralysis after acute spinal cord injury were system have been recognized in recent years. In this study, various factors concerning microcirculation and monoamines levels were compared between rabbits in which excitatory amino acid receptor (NMDA) antagonist MK801 administerd (MK801-treated group) and untreated controls (control group) after spinal cord injury.The following studies were performed.1)Evaluation of motor paralysis according to the Talov's evaluation.2)Determination of the spinal blood flow by laser doppler flowmetry.3)Quantitative determination of spinal edema by the dry weight method.4)Microdetermination of fluorescent materials (FD 70S) to detect changes in intraspinal vascular permeability.5)Determination of intraspinal monoamines and their metabolites by HPLC with electrochemical detection.Results1)Motor paralysis improved significantly in the MK801-treated group after 24 hours.2)Spinal blood flow was decreased after trauma substantially, but there was no signficant difference between the two groups during 6 hours after injury.3)Severity of the spinal edema in the MK801-treated group was significantly less than that in the control group, 1 hour and 6 hours after injury.4)An increase in intraspinal vascular permeability in the MK801-treated group was significantly less than that in the control group, one hour after injury.5)MHPG/NE ratio was significantly greater in the MK801-treated group than in the control group.The present study revealed that NMDA antagonist MK801 improved behavioral outcome, spinal edema, and vascular permeability after acute spinal cord injury. Therefore it was strongly suggested that NMDA plays an important role in the secondary spinal cord damage.