Indorenate improves motor function in rats with chronic spinal cord injury

The effect of indorenate (5-methoxytryptamine, beta-methyl carboxylate hydrochloride), a 5-HT1A agonist, was investigated on the motor performance of rats with chronic spinal cord injury. Four months after a ninth thoracic vertebrae spinal cord contusion, 29 rats were randomly allocated into two groups: saline solution and indorenate-treated animals with daily doses incremented at weekly intervals. The locomotor performance of all rats was measured by the Basso, Beattie, and Bresnahan (BBB) rating scale. The results showed that at the end of the treatment, the motor activity of indorenate group was significantly better than that presented by saline solution group. The 80% of indorenate, (against 15% of saline solution) did not show detriment on motor activity. When we analysed the motor activity of rats with basal BBB lower than 10, a significant improvement of motor recovery in indorenate-treated animals was observed. The benefits observed in locomotor function at low doses followed by increasing doses could be associated with pharmacological treatment by indorenate, a well-known 5-HT1A receptor agonist. Our results suggest a potential mechanism by which serotonergic agents may improve motor function in rats with chronic spinal cord injury.