Complete Transection of the Spinal Cord

Introduction

The spinal cord , which connects the brain and the peripheral nervous system , contains millions of neurons responsible for sending information throughout the body . Included in these nerve cells are those for balance and movement . When the spinal cord is injured , the organism may suffer paralysis and recovery from this can be aided by nerve growth factors also called neutrophins . This study aims to demonstrate the effect of spinal cord transection to test animals and the recovery of these animals with the aid of neutrophins (Coumans , et al

Methods

Spinal

cord transection was done using the procedures of Bregman and McAtee (1993 ) except that the tissue transplantation part was not performed . The test organisms are adult female rats , around 6-8 weeks old , with a weight of 200-250 grams before surgery . The spinal cord was transected with iridectomy scissors . Neutrophin was then administered to the animals subcutaneously . A gel foam soaked in saline solution was placed on top of the transplanted tissue and the muscle and skin covering the transection area were stitched back in place . Ten rats were used in this set-up . For comparative purposes , ten rats were subjected into the same transection surgery procedure , but were not given neutrophins . Ten rats were used as a control , which did not undergo transection and neutrophin administration . The 30 rats were given 20 cc /d of D5 lactated Ringer 's solution for hydration . The test animals were given antibiotics [sulfamethoxazole (4 mg /100 gm )-trimethoprim (0 .8 mg /100 gm )] to prevent infection . They were also given food and water inside their cages . The locomotor behavior of the animals was observed to determine the recovery of their spinal cord after the injury (Coumans et al , 2001

Results

Behavior of the test animals which were subjected to transection only transection with neutrophin administration , and not subjected to both transection and neutrophin administration (control ) were observed and recorded . Observation of movement and locomotor functions to determine the recovery of the rats were started right after the surgical procedure . The results agreed with those of Coumans et al (2001 . All the rats exhibited no voluntary movement of their hind limbs while taking steps . The animals dragged their extended hind limbs passively while being supported by their forelimbs . However , their locomotion functions started to vary 3 to 4 weeks after the transection . The animals which received transection only did not show improvement of their hind limb function . On the other hand , those which received neutrophin together with trasnsection showed improvement of hind limb weight support , nearly showing a pattern similar to that of the control rats . The test animals ' limb movements were further observed using stairs . The control animals (C ) showed full support of their weight using their limbs in each step . The animals which were subjected to transection only (T ) dragged their hind limbs while climbing . Those which were subjected to transection and were also administered neutrophins (T N ) exhibited improved hind limb function , with their weight supported in each step while climbing (Fig...