Histochemical demonstration of monoamine neuron systems in the human fetal brain

Abstract

Publisher Summary This chapter elaborates the histochemical demonstration of monoamine neuron systems in the human fetal brain. In chemical investigations on human fetal brain, significant but low concentrations of dopamine, noradrenaline and serotonin have been reported. The monoamine axon bundles had a notably high fluorescence in the fetal brain and could thus be traced for long distances through the lower brain stem, and the hypothalamus up to the basal ganglia and the septal region. One major system of CA fibers could be followed from the region of the lower medulla oblongata through pons and mesencephalon, and at the level of the red nucleus; it joined the medial forebrain bundle. Within the MFB, one system of CA fibers could be further traced up to the septal region. A second large system of ascending CA fibers was observed to originate in the fluorescent cell bodies in the substantia nigra and through the tegmental fields of Forel, the lateral hypothalamus and the zona incerta, ran into the internal capsule toward the basal ganglia.