Objective: To find out an effective fixative in immunohistochemistry for high-affinity neurotrophin receptor-tyrosine kinase (Trk) B. Methods: Comparing the results from four groups of adult rats which were fixed by d...Objective: To find out an effective fixative in immunohistochemistry for high-affinity neurotrophin receptor-tyrosine kinase (Trk) B. Methods: Comparing the results from four groups of adult rats which were fixed by different fixatives before the brain sections were processed for TrkB immunohistochemistry. Results: In the four groups, TrkB immunoreactive cells were observed throughout the whole brain, but the intensity of immunoreactive cells and the background staining exhibited a marked difference among the groups. Conclusion: Using 0.3%-0.5% paraformaldehyde in 75% saturated picric acid 0.1 mol/L di-sodium hydrogen phosphate buffer as the fixative may yield the best quality of TrkB immunoreactivity.展开更多
Purpose To review the spatiotemporal behaviours of central otolith neurons in decerebrate animals.Data sources Laboratory of Neurophysiology, Department of Physiology, Faculty of Medicine, The University of Hong Kong....Purpose To review the spatiotemporal behaviours of central otolith neurons in decerebrate animals.Data sources Laboratory of Neurophysiology, Department of Physiology, Faculty of Medicine, The University of Hong Kong.Data extraction Results of key research findings from 1992 to 1997.Results With constant velocity colckwise (CW) and counterclockwise (CCW) offvertical axis rotations as stimuli to the otolith organs, neurons in the vestibular nuclei and medullary reticular formation showed characteristic spatiotemporal behavious. Onedimensional neurons showed symmetric and stable bidirectional response sensitivities (δ) to change in velocity while twodimensional neurons showed asymmetric and variable δ to velocity. This CWCCW asymmetry to bidirectional rotations may provide directional coding in the modulation of neural signals. Vestibular nuclear neurons also displayed distinct spontaneous discharge patterns at the stationary and earthhorizontal position, indicating that one and twodimensional neurons belong to physiologically distinct etities. These spatiotemporal behavious of the vestibular nuclear neurons were also shown to be precisely controlled by imputs from the vestibulocerebellum and/or bilateral otoliths. In both the vestibular nucleus and the reticular formation, the best response orientations of one-dimensional neurons and the orientations of the maximum response vector of two-dimensional neurons were found to point in all directions close to the horizontal plane, indicating that all head orientations on this plane are encoded across an ensemble of neurons.Conclusion Otolithevoked behaviours of the one-dimensional and two-dimensional neurons constitute an important element for the recognition of the direction and orientation of head motion in space.展开更多
文摘Objective: To find out an effective fixative in immunohistochemistry for high-affinity neurotrophin receptor-tyrosine kinase (Trk) B. Methods: Comparing the results from four groups of adult rats which were fixed by different fixatives before the brain sections were processed for TrkB immunohistochemistry. Results: In the four groups, TrkB immunoreactive cells were observed throughout the whole brain, but the intensity of immunoreactive cells and the background staining exhibited a marked difference among the groups. Conclusion: Using 0.3%-0.5% paraformaldehyde in 75% saturated picric acid 0.1 mol/L di-sodium hydrogen phosphate buffer as the fixative may yield the best quality of TrkB immunoreactivity.
基金supported in part by the HKRGC-General Research Fund(No.777810)NSFC/RGC-Joint Research Scheme(No.N_HKU741/11)+2 种基金Innovation and Technology Fund(No.100/10)SK Yee Medical Research Fund,the National Natural Science Foundation of China(No.81000011,81272080)the Strategic Research Theme of the University Research Committee,The University of Hong Kong
文摘Purpose To review the spatiotemporal behaviours of central otolith neurons in decerebrate animals.Data sources Laboratory of Neurophysiology, Department of Physiology, Faculty of Medicine, The University of Hong Kong.Data extraction Results of key research findings from 1992 to 1997.Results With constant velocity colckwise (CW) and counterclockwise (CCW) offvertical axis rotations as stimuli to the otolith organs, neurons in the vestibular nuclei and medullary reticular formation showed characteristic spatiotemporal behavious. Onedimensional neurons showed symmetric and stable bidirectional response sensitivities (δ) to change in velocity while twodimensional neurons showed asymmetric and variable δ to velocity. This CWCCW asymmetry to bidirectional rotations may provide directional coding in the modulation of neural signals. Vestibular nuclear neurons also displayed distinct spontaneous discharge patterns at the stationary and earthhorizontal position, indicating that one and twodimensional neurons belong to physiologically distinct etities. These spatiotemporal behavious of the vestibular nuclear neurons were also shown to be precisely controlled by imputs from the vestibulocerebellum and/or bilateral otoliths. In both the vestibular nucleus and the reticular formation, the best response orientations of one-dimensional neurons and the orientations of the maximum response vector of two-dimensional neurons were found to point in all directions close to the horizontal plane, indicating that all head orientations on this plane are encoded across an ensemble of neurons.Conclusion Otolithevoked behaviours of the one-dimensional and two-dimensional neurons constitute an important element for the recognition of the direction and orientation of head motion in space.
