Laminar organization of efferent connections of the prefrontal cortex in the dog.
The method of retrograde HRP transport was used to study the laminar organization of cortico-subcortical and cortico-cortical connections of the dog's prefrontal cortex (PFC). The neurons of deep cortical layers VI and V gave rise to cortico-subcortical connections, while cortico-cortical connections originated from layers II-VI. Among them, the main source of intracortical connections was layer III. Differences in the distribution of labeled cells in sublayers IIIa and IIIb seemed to depend on the length of connections, e.g., local and distal as well as ipsi- and contralateral connections. The neurons which are a source of both cortico-subcortical and cortico-cortical connections were located more superficially in the medial PFC fields. Such distribution of neurons seems to be related to the differences of cytoarchitectonic structure of the medial and lateral PFC surface. Most frequently the projective neurons were of a pyramidal type, although some fusiform and stellate types were occasionally found.
D000818:Animals; D002540:Cerebral Cortex / Q000033:anatomy & histology*; D004285:Dogs; D004525:Efferent Pathways / Q000033:anatomy & histology; D005625:Frontal Lobe / Q000033:anatomy & histology*; D013787:Thalamic Nuclei / Q000033:anatomy & histology*