CONFOCAL MICROSCOPY AS A TOOL TO STUDY NEUROGENESIS IN THE RAT BRAIN

摘要

Repeated maternal separation in male Sprague Dawley rats (3 hours daily from postnatal day (PND) 2-14) mimics the behavioural aspects of depression and reduces adult neurogenesis. Conversely, exercise has been shown to promote neurogenesis which in turn has been linked to a reduction of depression-like behavior in mice. However, whether exercise would act similarly in depressed maternally separated rats remains unknown. This is the first study (to our knowledge) that attempts to compare neurogenesis in maternally separated and non-maternally separated rats by means of the novel thymidine analogue 5-ethynyl-2'-deoxyuridine (EdU) to label and identify proliferating cells. This marker was chosen as it does not require denaturation of the tissue and consequently allows for improved tissue quality and staining with cell-type specific markers, NeuN (a neuronal marker), doublecortin (DCX, an early neuronal marker), Ki-67 (a marker for cell proliferation) and glial fibrillary acidic protein (GFAP, a marker for glia). A pilot study used 16 rats and sought to characterize the use of the new label in conjunction with fluorescent markers for identification of neurogenic progenitors in the dentate gyrus of the hippocampus (Fig. 1).