[Classification of neurons of the visual cortex of the guinea pig (Cavia porcellus). A Golgi study].

In the visual cortex of the guinea pig stellate neurons in L IV and neurons with short axons were studied with the Golgi-method. We found spiny multipolar neurons in L IV (stellate cells in L IV), large spinefree neurons (basket cells), spinefree neurons with vertical or horizontal axonal distribution, small neurons with dense local dendritic and axonal plexuses (neurogliaform cells), sparsely spined polarized neurons with ascending axons (Martinotti-cells), small sparsely spined cells in L IV, spinefree bipolar neurons with vertical axons (bipolar cells), neurons with chandelier axons (chandelier cells) and sparsely spined bitufted neurons with dense vertical axonal plexuses (double bouquet cells). The analysis of neurons in the visual cortex of the guinea pig was undertaken to establish their number and distribution. Comparing the neurons of two species of rodentia, the diurnal guinea pig and the night-active rat we could found a higher variability of neurons in the guinea pig and a higher diversity of neuronal structures, which allows a better differentiation of cell types (e.g. double bouquet cells).