title: Neurogenesis and precursor cell differences in the dorsal and ventral adult canine hippocampus.
abstract: During evolution a unique anterior-posterior flexure posited the canine dentate gyrus in two distinct dorsal and ventral positions. We therefore sought to explore neurogenesis and neurogenic cell-related difference along the canine hippocampal dorsal-ventral axis. Post mortem histological analysis revealed 49.1% greater doublecortin (DCX)-positive cells and a 158.5% greater percentage of double labeled DCX-positive/neuronal nuclei (NeuN) positive cells in the dorsal subgranular zone compared to the ventral. We then show neural precursor cells isolated from fresh hippocampal tissue are capable of proliferating long term, and after differentiation, express neuronal and glial markers. Dorsal hippocampal isolates produced a 120.0% higher frequency of sphere-forming neural precursor cells compared to ventral hippocampal tissue. Histological DCX and neurosphere assay results were highly correlated. Overall, we provide the first evidence that the dorsal canine hippocampus has a markedly higher rate of adult neurogenesis than the ventral hippocampus, possibly related to a greater frequency of contributory neural precursor cells.
authors.affiliation: Regenerative Neuroscience Group, Brain and Mind Research Institute, University of Sydney, Australia; UNSW Stem Cell Laboratory, University of New South Wales (UNSW), Australia.
authors.forename: Aileen
authors.initials: A
authors.lastname: Lowe
authors.affiliation: Regenerative Neuroscience Group, Brain and Mind Research Institute, University of Sydney, Australia; Neuroscience Research Australia, Australia.
authors.forename: Marshall
authors.initials: M
authors.lastname: Dalton
authors.affiliation: UNSW Stem Cell Laboratory, University of New South Wales (UNSW), Australia.
authors.forename: Kuldip
authors.initials: K
authors.lastname: Sidhu
authors.affiliation: Centre for Healthy Brain Ageing, UNSW, Australia.
authors.forename: Perminder
authors.initials: P
authors.lastname: Sachdev
authors.affiliation: McKnight Brain Institute, University of Florida, Gainesville, USA.
authors.forename: Brent
authors.initials: B
authors.lastname: Reynolds
authors.affiliation: Regenerative Neuroscience Group, Brain and Mind Research Institute, University of Sydney, Australia. Electronic address: michael.valenzuela@sydney.edu.au.
authors.forename: Michael
authors.initials: M
authors.lastname: Valenzuela
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D018891:Dentate Gyrus / Q000033:anatomy & histology / Q000166:cytology; D004285:Dogs / Q000033:anatomy & histology*; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology / Q000166:cytology*; D008297:Male; D058953:Neural Stem Cells / Q000166:cytology*; D055495:Neurogenesis; D009457:Neuroglia / Q000166:cytology; D009474:Neurons / Q000166:cytology
keywords: Adult stem cells; Canine; Neural colony forming assay; Neurogenesis; Neuronal differentiation; Neuroprecursor