Neurogenesis in the dentate gyrus begins before birth but then continues into adulthood. Consequently, many newborn granule cells must integrate into a preexisting hippocampal network. Little is known about the timing of this process or the characteristics of the first established synapses. We used mice that transiently express enhanced green fluorescent protein in newborn granule cells to exam...

Neurogenesis is a constitutive activity in the adult dentate gyrus whereby new cells are created in the subgranular zone, before becoming neurons in the dentate gyrus granule cell layer. New granule cells are thought to migrate from the subgranular zone outwards to the edge of the cell layer as they mature. In these experiments we examined the dendritic morphology of granule cells in the subgra...

The well established anatomy of the cerebellar cortex has led to suggestions that cerebellar molecular layer interneurons laterally inhibit Purkinje cells. In support of the anatomical predictions, on-beam excitation and off-beam inhibition of Purkinje cells have been shown to occur when the surface of the cerebellum is electrically excited. Patchy excitation of Purkinje cells with flanking inh...

The hippocampal dentate gyrus is often viewed as a segregator of upstream information. Physiological support for such function has been hampered by a lack of well-defined characteristics that can identify granule cells and mossy cells. We developed an electrophysiology-based classification of dentate granule cells and mossy cells in mice that we validated by optogenetic tagging of mossy cells. ...

–In order to determine whether granule cell death stimulates the proliferation of granule cell precursors in the dentate gyrus of the adult rat, we performed both excitotoxic and mechanical lesions of the granule cell layer and examined the numbers of proliferating cells at different survival times. Using [H]thymidine autoradiography, bromodeoxyuridine labelling and proliferating cell nuclear a...

Proliferation of Schwann cells is one of the first events that occurs after contact with a growing axon. To further define the distribution and properties of this axonal mitogen, we have (a) cocultured cerebellar granule cells, which lack glial ensheathment in vivo with Schwann cells; and (b) exposed Schwann cell cultures to isolated granule cell membranes. Schwann cells cocultured with granule...

Platelets are known to contribute to vascular pathologies, however, their role in inflammatory disorders of the central nervous system (CNS), such as multiple sclerosis (MS) and its mouse model, experimental autoimmune encephalomyelitis (EAE), is thus far poorly defined. Although there is emerging evidence that platelets might accumulate in the CNS parenchyma along with an increased activation ...

Cerebellar granule cell progenitors proliferate postnatally in the upper part of the external granule cell layer (EGL) of the cerebellum. Postmitotic granule cells differentiate and migrate, tangentially in the EGL and then radially through the molecular and Purkinje cell layers. The molecular control of the transition between proliferation and differentiation in cerebellar granule cells is poo...

The brain is composed of diverse types of neurons that fulfill distinct roles in neuronal circuits, as manifested by the hippocampus, where pyramidal neurons and granule cells constitute functionally distinct domains: cornu ammonis (CA) and dentate gyrus (DG), respectively. Little is known about how these two types of neuron differentiate during hippocampal development, although a set of transc...