Cortical edema in moderate fluid percussion brain injury is attenuated by vagus nerve stimulation

• Published in: Neuroscience 2007-06, Vol.147 (2), p.286-293
• Main Authors: Clough, R.W, Neese, S.L, Sherill, L.K, Tan, A.A, Duke, A, Roosevelt, R.W, Browning, R.A, Smith, D.C
• Format: Article
• Language: English
• Subjects: Animals; Behavior, Animal - physiology; Biological and medical sciences; Brain Edema - etiology; Brain Edema - pathology; Brain Edema - therapy; Brain Injuries - complications; Brain Injuries - pathology; Brain Injuries - therapy; brain swelling; Cerebral Cortex - pathology; Electric Stimulation Therapy; FPI; Fundamental and applied biological sciences. Psychology; Injuries of the nervous system and the skull. Diseases due to physical agents; Locomotion - physiology; Male; Medical sciences; Neurology; Norepinephrine - metabolism; Postural Balance - physiology; Psychomotor Performance - physiology; Rats; Rats, Long-Evans; TBI; Traumas. Diseases due to physical agents; traumatic brain injury; Vagus Nerve - physiology; Vertebrates: nervous system and sense organs; VNS
• ISSN: 0306-4522; 1873-7544
• DOI: 10.1016/j.neuroscience.2007.04.043

Abstract Development of cerebral edema (intracellular and/or extracellular water accumulation) following traumatic brain injury contributes to mortality and morbidity that accompanies brain injury. Chronic intermittent vagus nerve stimulation (VNS) initiated at either 2 h or 24 h (VNS: 30 s train of 0.5 mA, 20 Hz, biphasic pulses every 30 min) following traumatic brain injury enhances recovery of motor and cognitive function in rats in the weeks following brain injury; however, the mechanisms of facilitated recovery are unknown. The present study examines the effects of VNS on development of acute cerebral edema following unilateral fluid percussion brain injury (FPI) in rats, concomitant with assessment of their behavioral recovery. Two hours following FPI, VNS was initiated. Behavioral testing, using both beam walk and locomotor placing tasks, was conducted at 1 and 2 days following FPI. Edema was measured 48 h post-FPI by the customary method of region-specific brain weights before and after complete dehydration. Results of this study replicated that VNS initiated at 2 h after FPI: 1) effectively facilitated the recovery of vestibulomotor function at 2 days after FPI assessed by beam walk performance ( P