Wed. Jun 19th, 2024

Pinal cord, Alexa-Fluor 488-labeled siRNA solution was intrathecally injected into the vicinity of the trauma. PMWs were then applied onto the dura mater (Fig. 2A). At five days after injury, the distributions of fluorescence originating from Alexa-Fluor 488labeled siRNA (green) and TRITC-labeled GFAP (red) were observed in sagittal sections of the injured spinal cords under three different treatment conditions: no treatment (SCI alone) as a control, siRNA injection alone, and PMW application after siRNA injection. Low-intensity green fluorescence in the SCI alone indicates autofluorescence (Fig. 2B). High-intensity fluorescence was observed in the subsurface region of the spinal tissue with siRNA injection alone, while high-intensity fluorescence was spread over a much broader and deeper region of the SCI with PMW application after siRNA 17460038 injection. Aggregation of GFAP was observed around the lesion site in all groups (Fig. 2B), indicating reactive astrogliosis in those regions. Magnified and overlaid fluorescence images of the injured spinal cords with PMW application revealed substantial incorporation of siRNA into GFAP-positive astrocytes (arrowheads, Fig. 2B). Figure 2C shows the integrated numbers of pixels showing green fluorescence in the images as a function of the depth range of 23408432 spinal tissues under the three Argipressin site conditions described above. The total number of pixels showing green fluorescence in the SCI alone condition, which ranged from 6000 to 10000, indicates the level of background autofluorescence. For the SCI with siRNA injection alone condition, the integrated number of pixels showing green fluorescence was much greater than the background level in the shallowest depth section (0?00 mm), but it rapidly decreased with increasing depth. In the PMW application group, on the other hand, a much higher fluorescence intensity level was observed across a wide range of depths of tissue (0?500 mm), demonstrating the capability of PMWs for efficient siRNA delivery into the anterior side of the spinal cord. Figure 2D shows the integrated numbers of pixels with yellow fluorescence, which indicates colocalization of siRNA with GFAP-positive astrocytes, in the images as a function of the depth of the spinal cord. The results demonstrate that delivered siRNA was retained in the glial cells located in a deep region from 1000 mm to 1500 mm in the anterior funiculus at five days post-SCI.Evaluation of Locomotive FunctionFor the three groups of rats, the SCI group, siRNA group and PMW group, the motor function of the hind limbs was evaluated by open-field testing and scored based on the BBB scale [39,40]; a score of 0 means no spontaneous movement while a score of 21 indicates normal locomotion (n = 12, each group). Assessment of the animals was performed before laminectomy and on days 1, 3, 5, 7, 10, 14, and 21 after the contused injury. The open-field consisted of a squared arena (45 cm690 cm) with 20-cm-height walls. All rats received manual bladder expression before the openfield test to eliminate possible behavior differences due to bladder fullness. Experienced handlers placed the rat in the center of the open field and moved the rat back to the center if the rat stopped moving at the edge of the field. The open-field testing was recorded on video tapes during a 3-min observation purchase AN-3199 period. Two examiners who performed the procedure were unaware of the groups to which the rats belonged.Statistical AnalysisStatistical analysis of the results.Pinal cord, Alexa-Fluor 488-labeled siRNA solution was intrathecally injected into the vicinity of the trauma. PMWs were then applied onto the dura mater (Fig. 2A). At five days after injury, the distributions of fluorescence originating from Alexa-Fluor 488labeled siRNA (green) and TRITC-labeled GFAP (red) were observed in sagittal sections of the injured spinal cords under three different treatment conditions: no treatment (SCI alone) as a control, siRNA injection alone, and PMW application after siRNA injection. Low-intensity green fluorescence in the SCI alone indicates autofluorescence (Fig. 2B). High-intensity fluorescence was observed in the subsurface region of the spinal tissue with siRNA injection alone, while high-intensity fluorescence was spread over a much broader and deeper region of the SCI with PMW application after siRNA 17460038 injection. Aggregation of GFAP was observed around the lesion site in all groups (Fig. 2B), indicating reactive astrogliosis in those regions. Magnified and overlaid fluorescence images of the injured spinal cords with PMW application revealed substantial incorporation of siRNA into GFAP-positive astrocytes (arrowheads, Fig. 2B). Figure 2C shows the integrated numbers of pixels showing green fluorescence in the images as a function of the depth range of 23408432 spinal tissues under the three conditions described above. The total number of pixels showing green fluorescence in the SCI alone condition, which ranged from 6000 to 10000, indicates the level of background autofluorescence. For the SCI with siRNA injection alone condition, the integrated number of pixels showing green fluorescence was much greater than the background level in the shallowest depth section (0?00 mm), but it rapidly decreased with increasing depth. In the PMW application group, on the other hand, a much higher fluorescence intensity level was observed across a wide range of depths of tissue (0?500 mm), demonstrating the capability of PMWs for efficient siRNA delivery into the anterior side of the spinal cord. Figure 2D shows the integrated numbers of pixels with yellow fluorescence, which indicates colocalization of siRNA with GFAP-positive astrocytes, in the images as a function of the depth of the spinal cord. The results demonstrate that delivered siRNA was retained in the glial cells located in a deep region from 1000 mm to 1500 mm in the anterior funiculus at five days post-SCI.Evaluation of Locomotive FunctionFor the three groups of rats, the SCI group, siRNA group and PMW group, the motor function of the hind limbs was evaluated by open-field testing and scored based on the BBB scale [39,40]; a score of 0 means no spontaneous movement while a score of 21 indicates normal locomotion (n = 12, each group). Assessment of the animals was performed before laminectomy and on days 1, 3, 5, 7, 10, 14, and 21 after the contused injury. The open-field consisted of a squared arena (45 cm690 cm) with 20-cm-height walls. All rats received manual bladder expression before the openfield test to eliminate possible behavior differences due to bladder fullness. Experienced handlers placed the rat in the center of the open field and moved the rat back to the center if the rat stopped moving at the edge of the field. The open-field testing was recorded on video tapes during a 3-min observation period. Two examiners who performed the procedure were unaware of the groups to which the rats belonged.Statistical AnalysisStatistical analysis of the results.