In adult dentate gyrus neurogenesis, the link between maturation of newborn neurons and their function, such as behavioral pattern separation, has remained puzzling. By analyzing a theoretical model, we show that switch from excitation to inhibition GABAergic input onto maturing cells is crucial for proper functional integration. When excitatory, cooperativity drives growth synapses become sens...

Identifying the brain regions and neuronal cell types that become active at the time of spontaneous seizures remains an important challenge for epilepsy research, and the involvement of dentate granule cells in early seizure events continues to be debated. Although Fos expression is commonly used to evaluate patterns of neuronal activation, there have been few studies of Fos localization after ...

Several lines of evidence indicate that cell birth in the adult rat dentate gyrus is regulated by adrenal steroids. The expression of adrenal steroid receptors by mitotic cells in the dentate gyrus would support the hypothesis that these hormones act directly on granule cell progenitors. We performed a survival time course of in vivo [3H]thymidine autoradiography combined with immunohistochemis...

Lef1 and other genes of the LEF1/TCF family of transcription factors are nuclear mediators of Wnt signaling. Here we examine the expression pattern and functional importance of Lef1 in the developing forebrain of the mouse. Lef1 is expressed in the developing hippocampus, and LEF1-deficient embryos lack dentate gyrus granule cells but contain glial cells and interneurons in the region of the de...

With aging there is a decline in the number of newly generated neurons in the dentate gyrus of the hippocampus. In rodents and tree shrews, this age-related decrease in neurogenesis is evident long before the animals become aged. No previous studies have investigated whether primates exhibit a similar decline in hippocampal neurogenesis with aging. To investigate this possibility, young to midd...

The dentate gyrus continues to produce new neurons in adult rodents. The possibility of differential regulation of neurogenesis within regions of the dentate gyrus is largely unexplored, despite several other aspects of this phenomenon being well characterized in a large number of studies. In this report, we describe an area located at the anterior pole of the dentate gyrus that consistently la...

We investigated the effects of injection of N-methyl-D-aspartate (NMDA) receptor antagonists, 2-amino-5-phosphonovalerate (APV) and 7-chlorokynurenate (7-Cl-Kyn), into the basolateral amygdala (BLA) on long-term potentiation (LTP) in the medial perforant path-dentate gyrus granule cell synapses of anesthetized rats. Injection of APV or 7-Cl-Kyn into the ipsilateral BLA did not affect the baseli...

The dentate gyrus is one of the few brain regions that show proliferation of neuronal precursors postnatally and in adult life. Proliferation in the dentate gyrus has been shown to be influenced by exercise, stress and drugs such as antidepressants. Traditionally, proliferation studies rely on the time consuming and subjective manual count of labeled cells. Here we adapted the Metamorph softwar...

Several thousand new neurons are produced each day in the adult mammalian hippocampus, among which only excitatory granule cells (GCs) have thus far been identified. In the present study, we used mutant Semliki Forest Virus vectors to express enhanced green fluorescent protein in the hippocampus, and observed that approximately 14% of newly generated neurons in the dentate gyrus of adult rats a...

Tooth loss has been shown to affect learning and memory in mice and increases the risk of Alzheimer's disease. The dentate gyrus is strongly associated with cognitive function. This study hypothesized that tooth loss affects neurons in the dentate gyrus. Adult male mice were randomly assigned to either the tooth loss group or normal control group. In the tooth loss group, the left maxillary and...