• Brewer KL and Nolan T (2003). Preliminary study of nicotinamide (vitamin b3) as a neuroprotective agent following experimental spinal cord injury. Acad Emerg Med 10:464. Summary: BACKGROUND: A transient increase in exictatory amino acids (EAA) is viewed as contributing to a "central cascade" of secondary pathological changes that occur following spinal cord injury (SCI). This EAA induced neurotoxicity occurs, in part, through the generation of nitric oxide (NO). In turn, NO-induced injury is mediated by ADP-ribosylation. The vitamin, nicotinamide (NAm), has been shown to be an inhibitor of poly-ATP ribose polymerase (PARP) and is effective in reducing neuronal loss and behavioral deficits in models of stroke and traumatic brain injury. OBJECTIVE: Determine the usefulness of a single systemic dose of NAm for protection against neuronal death following an experimental spinal cord injury in rats. METHODS: Male, Long-Evans rats were given intraspinal injections of 125 mM quisqualic acid (QUIS) which simulates the increase in extracellular glutamate that is known to occur following SCI. The treatment group (n = 5) was given a single i.p. injection of NAm (500 mg/kg), 30 minutes post-injury. Control animals (n = 5) recieved an equal volume of normal saline i.p. Animals were allowed to survive for 7 days at which time the spinal cords were removed, fixed in formalin, cut into 75-micron serial sections and stained with cresyl violet. Microscopic analysis was performed to assess the lesion volumes in each group of animals. RESULTS: Lesion analysis revealed that the administration of NAm reduced the lesion volume by 20.2% over the 1.5mm length of cord examined. While there was no difference in the size of the lesion at the epicenter of damage, the rostrocaudal extent of damage was reduced in the NAm group. CONCLUSIONS: NAm appears to be effective in reducing lesion size in this model of SCI. Because it can be used clinically in large doses with few side effects, further research into the use of NAm as a neuroprotective agent in SCI is warranted. In addition, studies are needed to detemine the optimal dosage(s) and therapeutic window for its use. Brody School of Medicine at East Carolina University: Greenville, NC.