Hippocampal network activity is predominantly coordinated by γ-amino-butyric acid (GABA)ergic neurons. We have previously hypothesized that the altered excitability of hippocampal neurons in Alzheimer's disease (AD), which manifests as increased in vivo susceptibility to seizures in the TgCRND8 mouse model of AD, may be related to disruption of hippocampal GABAergic neurons. In agreement, our p...

AIM To investigate the effects of phenytoin (DPH) on morphological and structural changes of pyramidal neurons in hippocampal CA3 of rats induced by chronic stress. METHODS Using Nissl staining, Golgi staining, and electron microscope, the morphology and structure of pyramidal neurons in hippocampal CA3 of rats were observed. RESULTS Chronic stress resulted in loss of hippocampal CA3 pyrami...

To investigate the activity of senescence-associated beta-galactosidase (SA-beta-GAL) in the hippocampus of aging rats. Hippocampi of 6-, 18-, and 24-month-old rats were observed by histochemical staining for SA-beta-GAL and cytochemical staining for SA-beta-GAL in cultured hippocampal neurons. The activity of SA-beta-GAL doubled in hippocampal pyramidal cells of the CA3 region in rats between ...

Sharp-wave ripples (SPW-Rs) in the hippocampus are implied in memory consolidation, as shown by observational and interventional experiments. However, the mechanism of their generation remains unclear. Using two-dimensional silicon probe arrays, we investigated the propagation of SPW-Rs across the hippocampal CA1, CA2, and CA3 subregions. Synchronous activation of CA2 ensembles preceded SPW-R-r...

Aging-related impairments in hippocampus-dependent cognition have been attributed to maladaptive changes in the functional properties of pyramidal neurons within the hippocampal subregions. Much evidence has come from work on CA1 pyramidal neurons, with CA3 pyramidal neurons receiving comparatively less attention despite its age-related hyperactivation being postulated to interfere with spatial...

Learning-related changes in strength in selected hippocampal synapses have been described recently. However, information is scarce regarding the spatial-temporal sequence of changes in synaptic weights taking place during the acquisition of a classical conditioning task and the contribution of both context (environmental details) and cues (conditioned and unconditioned stimuli: CS, US) to those...

The CA2 region of the mammalian hippocampus is a unique region with its own distinctive properties, inputs and pathologies. Disruption of inhibitory circuits in this region appears to be linked with the pathology of specific psychiatric disorders, promoting interest in its local circuitry, its role in hippocampal function and its dysfunction in disease. In previous studies, CA2 interneurons, in...

This article introduces a new experimental paradigm for the study of temporal lobe epilepsy. This approach utilizes the isolated guinea pig brain in vitro preparation, which generates a pattern of hypersynchronous neuronal activity similar to the peculiar 8-30 Hz rhythm characterizing stereoelectroencephalographic hippocampal recordings in human temporal lobe epilepsy. The present report descri...

Address for Correspondence: Dr. Hemamalini, Assistant Professor, Department of Anatomy, Jagadguru Sri Shivarathreeshwara Medical College, Mysore-570015, Karmataka, India. Phone number: +918762357259, Fax number: +91 821-2548345, 2493819 E-Mail: [email protected] Introduction: Centella asiatica is a perennial herbaceous creeper, growing in moist soil. It has anti-thrombotic, antibacteri...

Dendritic atrophy and impaired long-term synaptic potentiation (LTP) are hallmarks of chronic stress-induced plasticity in the hippocampus. It has been hypothesized that these disparate structural and physiological correlates of stress lead to hippocampal dysfunction by reducing postsynaptic dendritic surface, thereby adversely affecting the availability of synaptic inputs and suppressing LTP. ...