We studied changes in the expression of early genes in hippocampal cells in response to stimulation of the dorsal medial septal area (dMSA), leading to long-term potentiation in the hippocampus. Rats under urethane anesthesia were implanted with stimulating electrodes in the ventral hippocampal commissure and dMSA and a recording electrode in the CA1 area of the hippocampus. We found that high-frequency stimulation (HFS) of the dMSA led to the induction of long-term potentiation in the synapses formed by the ventral hippocampal commissure on the hippocampal CA1 neurons.
View Article and Find Full Text PDFRectal cancer occupies the leading position among cancers, and incidence of locally advanced recurrences is still high despite comprehensive treatment. Combined resections are usually associated with high perioperative risks. These procedures are technically complex interventions requiring further improvement.
View Article and Find Full Text PDFWe performed RNA sequencing of the dorsal and ventral parts of the hippocampus and compared it with previously published data to determine the differences in the dorsoventral gradients of gene expression that may result from biological or technical variability. Our data suggest that the dorsal and ventral parts of the hippocampus differ in the expression of genes related to signaling pathways mediated by classical neurotransmitters (glutamate, GABA, monoamines, etc.) as well as peptide and Wnt ligands.
View Article and Find Full Text PDFWe studied the effects of stimulation of the medial septal area on the gene expression in the dorsal and ventral hippocampus. Rats under urethane anesthesia were implanted with a recording electrode in the right hippocampus and stimulating electrode in the dorsal medial septum (dMS) or medial septal nucleus (MSN). After one-hour-long deep brain stimulation, we collected ipsi- and contralateral dorsal and ventral hippocampi.
View Article and Find Full Text PDFOne of the aspects of Alzheimer disease is loss of cholinergic neurons in the basal forebrain, which leads to development of cognitive impairment. Here, we used a model of cholinergic deficit caused by immunotoxin 192IgG-saporin to study possible beneficial effects of adeno-associated virus (AAV)-mediated overexpression of nerve growth factor (NGF) in the hippocampus of rats with cholinergic deficit. Suspension of recombinant AAV carrying control cassette or cassette with NGF was injected into both hippocampi of control rats or rats with cholinergic deficit induced by intraseptal injection of 192IgG-saporin.
View Article and Find Full Text PDFBoron-doped Czochralski-grown silicon wafers dominate the photovoltaic market. Light-induced degradation of these wafers is one of the most significant roadblocks for high-efficiency solar cells. Despite a very large number of publications on this topic, only a few studies have directly investigated the precursor of the defect responsible for this degradation.
View Article and Find Full Text PDFPurpose/aim: The role of cholinergic neurotransmission in the hippocampus remains controversial since different studies showed either no influence or its modulatory effect on glutamatergic hippocampal synapses. It remains unclear whether septal cholinergic input can modulate plasticity of synapses formed by CA3 pyramids on CA1 neurons. The aim of the study was to clarify the role of septal input in the development of LTP in this synapse.
View Article and Find Full Text PDFSaporin, which is extracted from , is a protein toxin that inactivates ribosomes. Saporin itself is non-selective toxin but acquires high specificity after conjugation with different ligands such as signaling peptides or antibodies to some surface proteins expressed in a chosen cell subpopulation. The saporin-based conjugated toxins were widely adopted in neuroscience as a convenient tool to induce highly selective degeneration of desired cell subpopulation.
View Article and Find Full Text PDFThis review aims at providing a retrospective, as well as a description of the state-of-the-art and future prospects regarding the theoretical and experimental characterisation of negative-defects in semiconductors. This is done by complementing the account with a description of the work that resulted in some of the most detailed, and yet more complex defect models in semiconductors. The essential physics underlying the negative-behaviour is presented, including electronic correlation, electron-phonon coupling, disproportionation, defect transition levels and rates.
View Article and Find Full Text PDFAlzheimer's disease (AD) is associated with degeneration of cholinergic neurons in the basal forebrain. Administration of the immunotoxin 192IgG-saporin to rats, an animal model of AD, leads to degeneration of cholinergic neurons in the medial septal area. In the present study, cholinergic cell death was induced by intracerebroventricular administration of 192IgG-saporin.
View Article and Find Full Text PDFDiverse epidermal appendages including grouped filaments closely resembling primitive feathers in non-avian theropods, are associated with skeletal elements in the primitive ornithischian dinosaur from the Kulinda locality in south-eastern Siberia. This discovery suggests that "feather-like" structures did not evolve exclusively in theropod dinosaurs, but were instead potentially widespread in the whole dinosaur clade. The dating of the Kulinda locality is therefore particularly important for reconstructing the evolution of "feather-like" structures in dinosaurs within a chronostratigraphic framework.
View Article and Find Full Text PDFMuscarinic acetylcholine receptors (mAChR) are known to be related to learning and memory processes. Inactivation of mAChR by cholinergic antagonists have been shown to produce amnesia in a variety of behavioral tasks. In this study, we investigated the role of M1 and M2 AChR on passive avoidance learning and plasticity of synapses formed by Schaffer collaterals in freely moving rats.
View Article and Find Full Text PDFOne of important aspects of development of Alzheimer's disease is degeneration of septal cholinergic neurons that innervate the hippocampus. We took advantage of widely used model of cholinergic deficit in the hippocampus, intracerebroventricular administration of IgG-saporin (Ig-saporin), to analyze the postponed consequences of cholinergic deficit in different parts of the hippocampus. We studied effects of the immunotoxin on the behavior of rats and gene expression in the dorsal and ventral hippocampus using RNA-seq approach.
View Article and Find Full Text PDFWe report on the observation of local reduction in generation threshold and enhancement in the output energy of a nanosecond Raman laser when the round-trip time of its cavity is matched with that of a longitudinally multimode pump laser or related to the latter as a ratio of small integers. We refer both observations to the synchronous pump effect originating from the periodicity in the small-scale intensity structure of the pump pulse.
View Article and Find Full Text PDFWnt signaling is involved in hippocampal development and synaptogenesis. Numerous recent studies have been focused on the role of Wnt ligands in the regulation of synaptic plasticity. Inhibitors and activators of canonical Wnt signaling were demonstrated to decrease or increase, respectively, in vitro long-term potentiation (LTP) maintenance in hippocampal slices (Chen et al.
View Article and Find Full Text PDFZh Vyssh Nerv Deiat Im I P Pavlova
January 2017
In the current paper there were used two methods for assessment of the propranolol effect on reactivated memory at reconsolidation phase--a classical pavlovian conditioning and the two-ways escape reflex. The difference between these two models was that in the first case a tone was paired with electrocutaneous painful stimulation only once, while in the second case it was applied multiply. Reminding was produced in the first case by placing the animals into the same context, whereas in the second case by application of the same amount of pairings of conditional and unconditional stimuli as it was used at the first day of learning.
View Article and Find Full Text PDFZh Vyssh Nerv Deiat Im I P Pavlova
December 2015
The review describes the Writ signaling pathway participation in the embryonic development, such as cell specification, migration and polarity. Recent studies have shown that the Wnt pathway plays one of the key roles in the processes of synaptic plasticity and memory formation. In this review there are evidences of the Wnt cascade involvement in the modulation of synaptic efficacy at both pre- and postsynaptic levels.
View Article and Find Full Text PDFWe have explored the potential neuroprotective effect of local lentiviraly-mediated overexpression of nerve growth factor (NGF) on in vivo long-term potentiation (LTP) in the rat hippocampus under pathological conditions. The suspension of lentiviral particles was prepared using a genetic construct containing the human NGF gene under the control of a neuron-specific CaMKII promoter. Two weeks after the viral injection NGF concentration in the hippocampus doubled.
View Article and Find Full Text PDFZh Vyssh Nerv Deiat Im I P Pavlova
April 2015
In this review the data on consolidation and reconsolidation of memory by its reactivation (reminding) by a conditional stimulus or context are presented. A special attention is paid to "time windows" when amnesic and other interventions during memory reconsolidation become effective. The similarities and differences between consolidation of original learning and repeated consolidation (reconsolidation) during reactivation of memory by a conditional stimulus or context are considered.
View Article and Find Full Text PDFZh Vyssh Nerv Deiat Im I P Pavlova
March 2015
We investigated a role of calcium in the mechanisms of deprivational potentiation (DeP) of the popspikes amplitude of CA1 neurons that was induced in consequence of long (60 min) interruption of rare test stimulation (0.05 Hz) of Schaffer collaterals in rat hippocampal slices. There are two phases of deprivational potentiation that have presumably different genesis: short-term initial "peak" (about 12 min) and long-term "plateau" (more than 1 h).
View Article and Find Full Text PDFTwo major neurotrophic factors, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are involved in a number of physiological processes associated with neuronal growth, survival and plasticity. There are an increasing number of papers demonstrating their ability to serve as neuroprotective molecules under various pathological conditions. At the same time, it remains unclear whether both NGF and BDNF have similar roles under pathological conditions and their effects on the electrophysiological properties of neurons after acute pathogen exposure.
View Article and Find Full Text PDFWe examined whether a non-selective antagonist of nAChRs mecamylamine and selective antagonists of α4β2-containing nAChRs dihydro-β-erythroidine (DHβE) and α7-containing nAChRs methyllycaconitine (MLA) affect learning performance and synaptic efficiency in the CA1 area of the hippocampus of freely moving rats during the memory consolidation period. Adult male Wistar rats received mecamylamine (0.5 mg/kg), DHβE (1 mg/kg), MLA (2 mg/kg) or saline immediately after training in a passive avoidance task.
View Article and Find Full Text PDFActa Neurobiol Exp (Wars)
April 2015
It is well-known that the cholinergic system and the muscarinic cholinergic receptors are associated with cognitive functions. Here we examined whether a non-selective muscarinic receptor antagonist scopolamine affects learning performance and/or synaptic plasticity during the memory consolidation period. Adult male Wistar rats (250-300 g) were injected with scopolamine (2 mg/kg) or saline immediately after training in a "passive avoidance" task.
View Article and Find Full Text PDFRoss Fiziol Zh Im I M Sechenova
December 2012
Wnt signaling is a signal transduction pathway involving peptides of Wnt family as key molecules. In this review, the data on the role of canonical and non-canonical Wnt pathway in hippocampal structural and synaptic plasticity have been analyzed. Wnt-mediated signal transduction is involved in normal functional plasticity, and the disturbances in Wnt-mediated mechanisms form a basis for the development of cerebral pathologies.
View Article and Find Full Text PDFMorphna paleo sp. n., the earliest winged representative of any living cockroach genus and the earliest representative of the family Blaberidae, is described from the Danian Arkhara-Boguchan coal mine in the Amur River region (Russian Far East).
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