Acute, subacute and chronic effect of cyclosporin-A on mean arterial pressure of rats with severe spinal cord contusion.

Cyclosporin-A (CsA) protects and regenerates the neural tissue after spinal cord (SC) injury. These beneficial effects are achieved when CsA is administered at a dose of 2.5mg/kg/12h during the first 2 days after lesion. In view of these observations, it is realistic to envision that, CsA could be tested in SC-clinical trials. Since CsA is a drug strongly related to hypertension, results imperative to evaluate experimentally the effect of the above CsA-dose regimen on blood pressure. For this purpose, one hundred and twenty adult rats were subjected (10 groups) or not (10 groups) to SC-injury. Five injured and five Sham-operated groups received CsA. The remaining groups received only vehicle. Mean arterial pressure (MAP) was recorded from these animals at acute (6 and 24h post surgery; p.s.), subacute (96h), or chronic (30 days) stages of injury. In the latter, the therapy (CsA or vehicle) was administered only during the first 2 days p.s. or daily during 30 days of follow-up. The results of this study showed that SC-injury by itself induces a significant decrease of MAP during the acute and subacute phases of injury. CsA therapy was able to reestablish MAP parameters to control values in these phases. Regardless the therapy, a reestablishment of MAP was observed in chronic stages. Only the daily administration of CsA induced a significant increase in MAP, however; such variation remained into the normal ranges of MAP for rats. The potential benefits offered by CsA support its usefulness after SC-injury.