Neuroprotection of completely lacerated spinal cord of adult rats by homotopic and heterotopic transplantation

The Morphofunctional Effect of the Transplantation of Bone Marrow Stromal Cells and Predegenerated Peripheral Nerve in Chronic Paraplegic Rat Model via Spinal Cord Transection

Functional recovery following spinal cord injury (SCI) is limited by poor axonal and cellular regeneration as well as the failure to replace damaged myelin. Employed separately, both the transplantation of the predegenerated peripheral nerve (PPN) and the transplantation of bone marrow stromal cells (BMSCs) have been shown to promote the regrowth and remyelination of the damaged central axons in SCI models of hemisection, transection, and contusion injury. With the aim to test the effects of the combined transplantation of PPN and BMSC on regrowth, remyelination, and locomotor function in an adult rat model of spinal cord (SC) transection, 39 Fischer 344 rats underwent SC transection at T9 level. Four weeks later they were randomly assigned to traumatic spinal cord injury (TSCI) without treatment, TSCI + Fibrin Glue (FG), TSCI + FG + PPN, and TSCI + FG + PPN + BMSCs. Eight weeks after, transplantation was carried out on immunofluorescence and electron microscope studies. The results showed greater axonal regrowth and remyelination in experimental groups TSCI + FG + PPN and TSCI + FG + PPN + BMSCs analyzed with GAP-43, neuritin, and myelin basic protein. It is concluded that the combined treatment of PPN and BMSCs is a favorable strategy for axonal regrowth and remyelination in a chronic SC transection model.

Amitriptyline pharmacokinetics in experimental spinal cord injury in the rabbit

Previous studies have demonstrated that pharmacokinetic behavior of several drugs such as paracetamol, theophylline, and aminoglycosides are significantly altered in spinal cord injured patients. No pharmacokinetic study of amitriptyline has been performed in patients and experimental models of spinal cord injury. Pharmacokinetic parameters of amitriptyline in orally treated rabbits subjected to laminectomy and spinal cord injury compared with those underwent laminectomy alone. Among twenty four male rabbits were included in this study, nine of them subjected to spinal cord injury at the 8(th) thoracic level by knife severance method and six rabbits underwent laminectomy alone (sham group) and nine rabbits treated as control. All received a single oral dose of amitriptyline (20 mg/kg) 24 h after injury. Blood sampling were done at predetermined times to 36 h after drug administration. Amitriptyline concentration in serum samples was determined by high-performance liquid chromatography. Pharmacokinetic parameters including maximum concentration (C(max)), time to reach maximum concentration (T(max)), half life, and the area under the curve to last detectable concentration time point (AUC(0-t)) were directly determined from the concentration-time curve. Maximum concentration was observed at 6.5 h after administration in sham group with a concentration of 439.6 ng/ml, whereas in SCI group T(max) was at 2.7 h with a concentration of 2763.9 ng/ml. In control group it was 3.3 h and 396 ng/ml, respectively. In SCI group, AUC was 9465.6 ng.h/ml and half life was 6 h and for control group it was 2817.4 ng.h/ml and 6.4 h, respectively. Statistical analysis of data showed that SCI didn't induce significant changes in amitriptyline pharmacokinetic parameters.