ELECTRON MICROSCOPIC OBSERVATIONS ON SYNAPSES IN THE HYPOTHALAMIC VENTROMEDIAL NUCLEUS OF THE RAT / 解剖学报

ABSTRACT

The types of synapses and some morphological features of the synaptic submicroscopic structures of rat hypothalamic ventromedial nucleus (HVM) have been described in this study. A total of 1 005 synapses is observed. The percentage of axo-dendritic synapse is 96.6%. It covers the majority of the total number of synapses. The percentage of axo-somatic synapse is 2.8% and axo-axonic synapse is 0.5% of the total number of the synapses. The crest synapse which is never reported in the HVM was found to be 0.1%. Its postsynaptic elements come from clubbed finger-like dendritic crest which is characterized by prominent postsynaptic membrane thickening and subsynaptic dense bodies. Two presynaptic terminals contact the wall of the crest process side by side and contain spheric vesicles. In the axo-dendritic and axo-somatic synapses, the parallel synapse (including synaptic complex), the tangent-like synapse and serial-like synapse have been observed.