Search

In pathogenesis of the traumatic disease of the spinal cord, two mechanisms of the injuries of its neuronal apparatus are defined: primary (necrosis) and secondary (apoptosis). In the work a participation of a number of internal causes in the progression of apoptosis in injury of the spinal cord and peripheral nerve trunks, the role of those remains little-studied up to date, is discussed.

Using rat model of spinal cord contusion injury at TVIII, we compared the effectiveness of immediate single transplantation of human mononuclear umbilical cord blood cells transfected with pBud-VEGF-FGF2 plasmid and immediate direct injection of the same plasmid into the lesion area. The results suggest that the delivery of therapeutic genes vegf and fgf2 in cells is more effective than direct injection of plasmid DNA with the same genes (judging from the number of myelinated fibers). Better tissue preservation and motor function recovery in experiments with direct injection of plasmid pBud-VEGF-FGF2 suggest that direct gene therapy seems to be an effective additional procedure to the method of gene delivery with transfected stem and progenitor cells.

Different mediator systems including serotoninergic one can influence animal's locomotor behavior. It has been shown that the spinal cord in the absence of supraspinal control is able to induce the locomotor activity in hindlimbs and afferent system can activate this mechanism. In behavioral studies on the rats with complete transection of the spinal cord it has been demonstrated that the pharmacological blocking of serotoninergic system results in depression of motor activity mediated by activation of support reactions. Histological studies did not reveal any effects of activation of support reactions on the safety of neurons as well as on the distribution of synaptic contacts within L2-L4 spinal segments. At the same time it has been shown that blockade of the serotoninergic system results in alterations of cells located in 1-3 laminae of dorsal horns, and in 7 Rexed's lamina as well as in redistribution of synaptic contacts in 1-4 Rexed laminae of the spinal cord dorsal horns.

Effects of immediate single transplantation of human umbilical cord blood mononuclear cells (UCB-MC) transfected with recombinant vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF2) genes into the area of injury were studied on the model of rat spinal cord dosed contusion at TVIII level. UCB-MC transfected with EGFP-N2 plasmid were transplanted into the rats of the control group under similar conditions. The presence of EGFP- labeled cells were traced in white matter during 21 days after transplantation at a distance no less than 10 mm in rostral and caudal directions from the nearest point of the injection. By 30 days after the transplantation of UCB-MC transfected with pBud-VEGF-FGF2 plasmid, the cross-sectional area of sparing grey matter increased by more than 60% at a distance of 3 mm from the epicenter of injury. By that time, in the animals of this group, the number of perivascular cells expressing beta receptor of platelet-derived growth factor (PDGFbetaR) was increased by an average of 30% in the outer zones of white matter 1.5 cm from the injury epicenter. Delivery of the therapeutic genes VEGF and FGF2 to the damaged region and their expression in cell carriers stimulates vascularization and post-traumatic spinal cord regeneration.

This paper is devoted to the analysis of the results of the author's investigations concerning spinal cord injuries. The voluminous material obtained with the use of up-to-date research methods (histological, histochemical, and biochemical) includes basic data on the mechanisms of regulation of blood circulation under normal conditions and in the case of a mechanical injury. It is shown that pathological morphological changes in the affected areas of the spinal cord as well as activities of transport enzymes in the capillaries and the reactive processes in the monoaminoergic nervous apparatus of he arteries may be used as the objective criteria for the determination of the time of the injury. The results of these studies find application in the practical diagnostic work for the estimation of the time of the spinal cord injury.

In animal experiments with spinal lesions, phylo- and ontogenetic features of development of plasticity in the CNS of mammals and high reliability of the CNS have been demonstrated. It has been shown that possibilities of compensation processes and the upper limit of plasticity increase in phylogeny. Much attention has been attached to the higher regions of the CNS and hypothalamus as well as to ecological and biological characteristics of animals. Changes in the structure and functions of the damaged spinal cord have been studied. The significance of sympathetic innervation and involvement of ATP and ATPase in the spinal cord functioning after injury have been demonstrated. The article reviews the investigations of the role of the cicatrixce and some endocrine glands (adrenal glands, pancreas, and thyroid gland) performed at the laboratory. In phylogeny, high plasticity has been demonstrated at early ontogenetic stages. Enzymes have been shown to facilitate recovery of spinal functions after injury.

Changes in the adrenergic nervous system and population of tissue basophils of human spinal arteries in the course of 24 h after a blunt injury to the spine were studied. A staged pattern of development of compensatory adaptive reaction of the mechanisms regulating the spinal circulation has been revealed. The detected time course of posttraumatic changes may be interesting as it concerns the diagnosis of the time when a blunt injury to the spine was inflicted.

The author studied the brains of 7 cats following the 30th and 90th days after lateral hemisections of the spinal cord on the superior cervical (2-3 segment) level and the brains of 7 control intact cats. The quantitative (cytointerpherometric) and morphological studies depicted an accumulation of dense substances (proteins) in the cytoplasma in the nuclei of the efferent neurons of the 5th layer of the motor cortex, in the nucleus rubri, Deyters nucleus and in the gigantic cells of the reticular nuclei on the intact side accompanied by an increase in the cells and an increase in the amount of satellites. More vivid and initial changes were seen in the cortex. The results are considered as structural and metabolic signs of a compensatory process conditioning the restitution of motor functions.