EM study on Phaseolus vulgaris lectin labelled terminals of rotundal fibers and on GABA immunogold stained structures in chicken ectostriatum centrale.

After having iontophoretically injected Phaseolus vulgaris Lectin into nucleus rotundus, labelled terminals were examined in ectostriatum centrale by EM. These terminals contained round synaptic vesicles. They were observed earlier by Golgi method and proved to be of rotundal origin by Phaseolus Lectin tracing method. The labelled terminals establish synapses, on large and small dendritic truncs of projection and local circuit neurons, and also contact spines and dendritic processes of projection neurons. They were observed on soma of GABA immunopositive local circuit neurons, and also on dendrites. Some observations completed the already known data on fine structure of the chicken ectostriatum centrale.