ABSTRACT
A central objective in deciphering the nervous system in health and disease is to define the connections of neurons. The propensity of neurotropic viruses to spread among synaptically-linked neurons makes them ideal for mapping neural circuits. So far, several classes of viral neuronal tracers have become available and provide a powerful toolbox for delineating neural networks. In this paper, we review the recent developments of neurotropic viral tracers and highlight their unique properties in revealing patterns of neuronal connections.
ABSTRACT
Spinal cord injury is one of the important field of neuroscience, and neural tract tracing techniques are important research tools. The neural fiber types in the spinal cord are complex, and there are some difference in structures between human beings and animals. This article reviewed different types of neural fibers closely related with spinal cord injury and regeneration, the difference between human beings and animals, and the application of neural tract tracing techniques in the study of spinal cord injury and regeneration.
ABSTRACT
Objective To investigate the expression of histamine in the cardiac sympathetic fibers from the guinea pig superior cervical ganglion and its coexistence with norepinephrine so as to provide morphological evidence for histamine as a cardiac sympathetic neurotransmitter.Methods Biotinylated dextranamine(BDA) anterograde tracing and immunofluorescence histochemical staining for histamine/norepinephrine were applied.Results After injection of BDA into the superior cervical ganglion,BDA labeled sympathetic fibers in the left and right atria and ventricle were observed.Meanwhile,the tracing fibers proved histamine-like immunoreactive or both histamine and norepinephrine-like immunoreactive.Conclusion Histamine is expressed in the cardiac sympathetic fibers from the guinea pig superior cervical ganglion and coexisted with norepinephrine.