RESUMO
The present work was performed to establish whether pre-injury administration of the 21-Aminosteroid, U-74389F, is beneficial for treatment of acute spinal cord trauma in rats, as it has been demonstrated that the bolus administration of the same compound one hour after injury facilitates the return of the spinal cord function as measured by electrophysiological recordings in this compression animal model of spinal cord trauma. Cortical somatosensory evoked potentials (CSSEPs) were recorded as an indicator of spinal cord function before and after a severe compression injury. Vital signs and the CSSEPs were monitored up to five hours post-injury. U-4389F treatment was given as a single injection (15 mg kg-1) one hour prior to the injury which was followed by a continuous infusion (3 mg kg-1h-1) during the procedure. The CSSEPs were abolished immediately after this injury both, in the untreated and treated animal groups. The majority of the treated animals (80%) demonstrated recovery of the CSSEPs within the second hour post-injury. The control group showed 40% recovery at this time period. At five hours post-injury, recovery rates were 47% and 87% for control and treated groups respectively. We conclude that the administration of the 21-Aminosteroid, U74389F, one hour prior to spinal cord injury facilitates the return of spinal cord function as measured by CSSEPs in a compression rat model of acute spinal cord trauma, supporting and verifying our previous experiences using the same compound as i.v. bolus injections one, two and three hours after the trauma, respectively.
Assuntos
Antioxidantes/farmacologia , Córtex Cerebral/fisiopatologia , Pregnatrienos/farmacologia , Compressão da Medula Espinal/fisiopatologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiologia , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Masculino , Pré-Medicação , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
The effect of bolus injections of 21-aminosteroid U74389F after an acute spinal cord compression trauma in rats was studied. Cortical somatosensory evoked potentials (CSEPs) were recorded before and after a weight-induced injury of 120 g and monitored up to five hours post-injury. All U74389F treatments were given as i.v. bolus injections of 15, 7.5, and 3.75 mg kg-1 at 1, 2, 3 h after the trauma, respectively. The CSEPs were abolished immediately after the injury in the control and treated animals. The majority of the treated animals (88.8%) demonstrated a return of the CSEPs within the second hour post-injury. In contrast, the animals in the control group showed only 44.4% recovery at this time period. At three hours post-injury, U74389F-treated animals (n = 18) showed a full recovery (100%) while the recovery rate remained at 44.4% for the control animals. We conclude that the bolus administration of U74389F one hour after injury facilitates the return of the spinal cord function as measured by the CSEPs in this compression model of acute spinal cord trauma.
