Sodium Cromoglycate Decreases Sensorimotor Impairment And Hippocampal Alterations Induced By Severe Traumatic Brain Injury In Rats

Severe traumatic brain injury (TBI) results in significant functional disturbances in the hippocampus. Studies support that sodium cromoglycate (CG) induces neuroprotective effects. This study focused on investigating the effects of post-TBI subchronic administration of CG on hippocampal hyperexcitability and damage as well as on sensorimotor impairment in rats. In contrast to the control group (Sham+SS group), animals undergoing severe TBI (TBI+SS group) showed sensorimotor dysfunction over the experimental post-TBI period (day 2, 55%,p < 0.001; day 23, 39.5%,p < 0.001; day 30, 38.6%,p < 0.01). On day 30 post-TBI, TBI+SS group showed neuronal hyperexcitability (63.3%,p < 0.01). The hippocampus ipsilateral to the injury showed volume reduction (14.4%, p < 0.001) with a volume of damage of 0.15 +/- 0.09 mm(3). These changes were associated with neuronal loss in the dentate gyrus (ipsilateral, 33%,p < 0.05); hilus (ipsilateral, 77%,p < 0.001; contralateral, 51%,p < 0.001); Cornu Ammonis (CA)1 (ipsilateral, 40%,p < 0.01), and CA3 (ipsilateral, 52%,p < 0.001; contralateral, 34%,p < 0.01). Animals receiving subchronic treatment with CG (50 mg/kg, s.c. daily for 10 days) after TBI (TBI+CG group) displayed a sensorimotor dysfunction less evident than that of the TBI+SS group (p < 0.001). Their hippocampal excitability was similar to that of the Sham+SS group (p = 0.21). The TBI+CG group presented hippocampal volume reduction (12.7%,p = 0.94) and damage (0.10 +/- 0.03 mm(3),p > 0.99) similar to the TBI+SS group. However, their hippocampal neuronal preservation was similar to that of the Sham+SS group. These results indicate that CG represents an appropriate and novel pharmacological strategy to reduce the long-term sensorimotor impairment and hippocampal damage and hyperexcitability that result as consequences of severe TBI.