[Investigation on the cytoarchitecture of the nucleus accumbens septi of rat (author's transl)].

The nucleus accumbens septi of the normal adult rat was investigated by means of the rapid Golgi impregnation technique according to Valverde (1970). 5 neuron types could be differentiated: type 1: spiny neurons; type 2: few spiny neurons; type 3: aspiny giant neurons; type 4: spiny spindle shaped neurons; type 5: aspiny spidery neurons. The types 1, 4 and 5, resp., are considered, with respect to morphological criteria, to represent interneurons, whereas the types 2 and 3 are considered to be accumbens output neurons. The cytoarchitecture of the nc. accumbens septi thus displays striking similarities with the caudate-putamen-complex. An hypothetical correlation of these neurons in a functional -- biochemical sense as well as their position in the nc. accumbens which is suggested to be a transition area between limbic and extrapyramidal motor systems, is discussed.