We examined the effects of long-term adrenalectomy (ADX) on hippocampal anatomy and behavioral learning in two spatial memory tasks. We assessed damage throughout the hippocampus by stereological analysis of the dentate gyrus and Ammon's horn. Rats were ADX or sham operated, and then tested in the Morris water maze 12 weeks after surgery, followed by testing on an eight-arm, alternating-baited ...

The dentate gyrus is one of only two regions of the mammalian brain where substantial neurogenesis occurs postnatally. However, detailed quantitative information about the postnatal structural maturation of the primate dentate gyrus is meager. We performed design-based, stereological studies of neuron number and size, and volume of the dentate gyrus layers in rhesus macaque monkeys (Macaca mula...

Previously, we observed that electroacupuncture (EA) at ST36 (Zusanli) and GV20 (Baihui) enhanced cell proliferation and neuroblast differentiation in the rat dentate gyrus. In this study, we investigated the possible mechanisms of EA in this effect. For this, we applied EA at ST36 and GV20 of Wistar rats (13-week-old) once a day for 3 weeks. Application of EA at these acupoints significantly i...

The dentate gyrus, an important anatomic structure of the hippocampal formation, is one of the major areas in which neurogenesis takes place in the adult mammalian brain. Neurogenesis in the dentate gyrus is thought to play an important role in hippocampus-dependent learning and memory. Neurogenesis has been reported to be increased in the dentate gyrus of patients with Alzheimer disease, but i...

The dentate gyrus of the hippocampus is uniquely organized with a displaced proliferative zone that continues to generate dentate granule cells throughout life. We have analyzed the expression of Notch receptors, Notch ligands, and basic helix-loop-helix (bHLH) genes during dentate gyrus development to determine whether the need to maintain a pool of undifferentiated precursors is reflected in ...

anethum graveolens or dill (local name: shevid) belongs to the family of apiaceae (umbelliferae) and is used traditionally for the treatment of convulsion and diabetes in iran. this study aimed to investigate the effect of hydroalcoholic extract of a. graveolens leaves on the histology of the dentate gyrus of the hippocampus in the epileptic mice kindled by pentylenetetrazole (ptz). in this exp...

The effects of semi-chronic stress on neuronal morphology and choline acetyltransferase were studied by injecting rats with dexamethasone. It was found that in the dexamethasone-treated rats the choline acetyltransferase activity had increased in the area where the fibers from the perforant pathway synapse with the granular cell layer of the dentate gyrus and also where the mossy fibers of the ...

The basolateral amygdala (BLA) has substantial effects on the neuronal transmission and synaptic plasticity processes through the dentate gyrus. Orexin neuropeptides play different roles in the sleep/wakefulness cycle, feeding, learning, and memory. The present study was conducted to investigate the function of the orexin receptors of the BLA in the hippocampal local interneuron circuits. For t...

The predominant excitatory synaptic input to the hippocampus arises from entorhinal cortical axons that synapse with dentate granule cells, which in turn synapse with CA3 pyramidal cells. Thus, two highly excitable brain areas – the entorhinal cortex and the CA3 field – are separated by dentate granule cells, which have been proposed to function as a gate or filter. However, unlike rats, primat...

Cell proliferation and differentiation are interdependent processes. Here, we have asked to what extent the two processes of neural progenitor cell amplification and differentiation are functionally separated. Thus, we analyzed whether it is possible to rescue a defect of terminal differentiation in progenitor cells of the dentate gyrus, where new neurons are generated throughout life, by induc...