Cytoarchitectonic organization of the entorhinal cortex of the canine brain.

The present study describes the cytoarchitectonic and chemoarchitectonic organization of the canine entorhinal cortex (EC). We distinguished medial, laterodorsal, and latero-intermediate subdivisions based on the organization of cortical layers using Nissl and Timm staining and AChE histochemistry. The medial subdivision is located at the border of the parasubiculum and is characterized by a narrow cortex, wide layer II, and densely packed cells in layer V.

Cytoarchitecture and thalamic afferents of the sylvian and composite posterior gyri of the canine temporal cortex.

The composite posterior and sylvian gyri of the canine temporal cortex show cytoarchitectonic features of poorly differentiated isocortex. Quantitative evaluation of connections examined with retrogradely transported fluorescent tracers indicated that both gyri received strong thalamic projections from the medial geniculate body (MG) and the lateromedial-suprageniculate (LM-Sg) complex, and a weaker projection from the posterior (Po) nuclei. On the basis of the connectivity patterns and cytoarchitectonic features we distinguished the anterior (CPa) and posterior (CPp) areas in posterior composite gyrus and the anterior (SA), dorsal (SD) and posterior (SP) sylvian areas.

Cytoarchitecture of the canine perirhinal and postrhinal cortex.

The perirhinal cortex in the dog's brain is composed of two traditional Brodmann's areas: 35 and 36. Area 35 is situated along the entire rostro-caudal extent of the fundus of the posterior rhinal sulcus, whereas area 36 occupies its lateral bank. In this study, four subdivisions were distinguished in area 35 based on cytoarchitectonic differentiation.

Changes of the acoustic startle reflex in rats with radiation-induced hippocampal lesion.

The main question of the study was: to what extent does a neonatal radiation-induced hippocampal lesion lead to emotional changes in adulthood? Acoustic startle response (ASR) was studied in two groups of adult rats. The rats from the first group (14 animals) were exposed to neonatal x-ray irradiation. Their ASR were compared with those from the 10 intact rats that formed a control group.