Background/Aim. Nucleus accumbens is a part of the ventral striatum also
known as a drug active brain region, especially related with drug addiction.
The aim of the study was to investigate the Golgi morphology of the nucleus
accumbens neurons. Methods. The study was performed on the frontal and
sagittal sections of 15 human brains by the Golgi Kopsch method. We
classified neurons in the human nucleus accumbens according to their
morphology and size into four types: type I - fusiform neurons; type II -
fusiform neurons with lateral dendrite, arising from a part of the cell body;
type III - pyramidal-like neuron; type IV - multipolar neuron. The medium
spiny neurons, which are mostly noted regarding to the drug addictive
conditions of the brain, correspond to the type IV - multipolar neurons.
Results. Two regions of human nucleus accumbens could be clearly recognized
on Nissl and Golgi preparations each containing different predominant
neuronal types. Central part of nucleus accumbens, core region, has a low
density of impregnated neurons with predominant type III, pyramidal-like
neurons, with spines on secondary branches and rare type IV, multipolar
neurons. Contrary to the core, peripheral region, shell of nucleus, has a
high density of impregnated neurons predominantly contained of type I and
type IV - multipolar neurons, which all are rich in spines on secondary and
tertiary dendritic branches. Conclusion. Our results indicate great
morphological variability of human nucleus accumbens neurons. This requires
further investigations and clarifying clinical significance of this important
brain region.