Cyto- and synaptogenesis in the arcuate nucleus of the rat hypothalamus during fetal and early postnatal life.

摘要: Morphogenesis of the arcuate nucleus rat from 15th fetal day to 6th postnatal was investigated light and electron microscopically. The neurons exhibit a gradual development after day. All cytoplasmic constituents are present in these nerve cells already during last days gestation. Nevertheless, they not fully differentiated at birth. first synapse-like structures (presynapses) were observed 17 day-old, synapses 18 day-old fetuses. During early period number presynapses decreases, but same time there is increase relatively mature synapses. This process starts prenatal life. Although all structural elements adult appear be birth, extent neuropil area indicate that still fairly undeveloped stage days.