The effect of calcium channel blockers in experimental spinal cord injury.

The therapeutic effect of calcium channel blockers (nifedipine) was studied in 40 rabbits with acute experimental spinal cord injury. In 30 animals, doses of 2.50 mg/day were orally administered for 10 days (after injury) whereas 10 animals received the same treatment 5 days before and 10 days after injury. The clinical evolution was assessed on a 5-graded scale (clinical marker of the motor deficit) and compared with the clinical evolution of a control group (20 rabbits with untreated spinal cord injury). The animals were sacrificed after 14 days of post-traumatic evolution (death occurring in some of them during this time interval). The mean of motor score was identical in both treated animal groups but significantly higher than in controls. Histopathological findings revealed various degrees of damage at injury site (hemorrhagic necrosis in the central gray matter, ischemic-type neuronal alterations, mesenchyme-glial reaction, demyelination) correlated with the degree of functional loss.