title: Fractal dimension of apical dendritic arborization differs in the superficial and the deep pyramidal neurons of the rat cerebral neocortex.
abstract: Pyramidal neurons of the mammalian cerebral cortex have specific structure and pattern of organization that involves the presence of apical dendrite. Morphology of the apical dendrite is well-known, but quantification of its complexity still remains open. Fractal analysis has proved to be a valuable method for analyzing the complexity of dendrite morphology. The aim of this study was to establish the fractal dimension of apical dendrite arborization of pyramidal neurons in distinct neocortical laminae by using the modified box-counting method. A total of thirty, Golgi impregnated neurons from the rat brain were analyzed: 15 superficial (cell bodies located within lamina II-III), and 15 deep pyramidal neurons (cell bodies situated within lamina V-VI). Analysis of topological parameters of apical dendrite arborization showed no statistical differences except in total dendritic length (p=0.02), indicating considerable homogeneity between the two groups of neurons. On the other hand, average fractal dimension of apical dendrite was 1.33±0.06 for the superficial and 1.24±0.04 for the deep cortical neurons, showing statistically significant difference between these two groups (p<0.001). In conclusion, according to the fractal dimension values, apical dendrites of the superficial pyramidal neurons tend to show higher structural complexity compared to the deep ones.
authors.affiliation: Institute of Histology and Embryology "Aleksandar Đ. Kostić", School of Medicine, University of Belgrade, Višegradska 26, 11000 Belgrade, Serbia. Electronic address: nela@dr.com.
authors.forename: Nela
authors.initials: N
authors.lastname: Puškaš
authors.affiliation: Institute of Histology and Embryology "Aleksandar Đ. Kostić", School of Medicine, University of Belgrade, Višegradska 26, 11000 Belgrade, Serbia. Electronic address: ivan.zaletel@mfub.bg.ac.rs.
authors.forename: Ivan
authors.initials: I
authors.lastname: Zaletel
authors.affiliation: Institute of Histology and Embryology "Aleksandar Đ. Kostić", School of Medicine, University of Belgrade, Višegradska 26, 11000 Belgrade, Serbia. Electronic address: s_bratislav@ikomline.net.
authors.forename: Bratislav D
authors.initials: BD
authors.lastname: Stefanović
authors.affiliation: Department of Biophysics, School of Medicine, University of Belgrade, Višegradska 26, Belgrade, Serbia. Electronic address: dusan@ristanovic.com.
authors.forename: Dušan
authors.initials: D
authors.lastname: Ristanović
mesh_terms: D000818:Animals; D003712:Dendrites / Q000648:ultrastructure; D017709:Fractals; D008297:Male; D019579:Neocortex / Q000166:cytology*; D017966:Pyramidal Cells / Q000648:ultrastructure*; D017208:Rats, Wistar
keywords: Apical dendrite; Cortical pyramidal neurons; Dendrite complexity; Dendritic morphology; Fractal analysis; Golgi technique; Rat neocortex