N. Marklund et al., alpha-Phenyl-tert-N-butyl nitrone (PBN) improves functional and morphological outcome after cortical contusion injury in the rat, ACT NEUROCH, 143(1), 2001, pp. 73-81
alpha -Phenyl-tert-N-butyl nitrone (BBN), a potent reactive oxygen species
(ROS) scavenger, has shown robust neuroprotective properties in several mod
els of acute brain injury, although not previously evaluated in traumatic b
rain injury (TBI). In this study, we assessed the potential efficacy of PEN
in a weight drop model producing a controlled cortical contusion. Sham ope
ration, mild or severe injury was induced in intubated and ventilated rats
and functional and morphological outcome was used as end-points at two week
s postinjury. In the trauma groups, saline or PEN (30 mg/kg) was injected a
s an intravenous bolus 30 minutes prior to injury. At day 11-15 post-injury
, cognitive disturbance was assessed using the Morris Water Maze (MWM) and
estimation of lesion volume and hemispheric loss of tissue was made. No cha
nge in MWM performance were found in either of the mildly traumatized group
s as compared to uninjured controls. In contrast, a significant decrease in
total mean latency and increase in path length in the severely traumatized
rats were found. PEN-treatment significantly improved MWM performance as c
ompared to saline treatment at the severe injury level (p < 0.05). The mild
injury level caused a discrete atrophy of the ipsilateral cortex with no e
ffect of PEN treatment. The severe injury caused a substantial loss of ipsi
lateral hemispheric tissue and a large cortical cavitation. PEN pre-treatme
nt significantly reduced the lesion volume and reduced hemispheric loss of
tissue at this injury level (p < 0.05).
Our results support the involvement of ROS in the injury process contributi
ng to the tissue loss and cognitive disturbance after TBI. The potential cl
inical utility of PEN will have to be assessed using a post-injury dosing r
egime.