1,721,049 research outputs found
Glutamate immunoreactivity in the rat cerebral cortex is reversibly abolished by 6-diazo-5-oxo-L-norleucine (DON), an inhibitor of phosphate-activated glutaminase.
No full textEffetti dello stress sui sistemi biologici. Possiamo misurarli?
No full textLo stress cronico, fisico e psicosociale, rappresenta un rischio per la nostra salute.
Numerosi studi clinici ed epidemiologici lo vanno dicendo ormai da tempo e il
ventaglio di patologie associate allo stress è divenuto oggi molto ampio, dalle
malattie infettive a quelle croniche metaboliche, fino ai tumori (Chrousos, 2009).
Eventi avversi, isolamento sociale, esagerate richieste dall’ambiente sociale e
familiare, ma anche condizioni lavorative insoddisfacenti o particolarmente
faticose e turni di lavoro irregolari, sono tutte situazioni capaci di indurre risposte
nell’organismo che, se ripetute o protratte, diventano maladattative e
compromettono le funzioni psicologiche, comportamentali e fisiologiche
dell’individuo. Di qui il rischio di sviluppare disfunzioni dei sistemi regolatori
dell’organismo che, nel lungo periodo, possono eventualmente sfociare in
patologie conclamate
Changes in glutamate immunoreactivity in the somatic sensory cortex of adult monkeys induced by nerve cuts.
No full textPostnatal development of high-affinity plasma membrane GABA transporters GAT-2 and GAT-3 in the rat cerebral cortex
No full textWe investigated the developmental profile of plasma membrane γ-aminobutyric acid (GABA) transporters (GATs) GAT-2 and GAT-3 expression by immunocytochemistry with affinity-purified polyclonal antibodies in the rat neocortex. At all developmental ages investigated, GAT-2 ir was prominent in the arachnoid and in the trabeculae of the subarachnoid space, whereas it was weak within the cortical parenchyma; the adult pattern was reached during the third week of postnatal life. GAT-3 ir was present at birth and increased rapidly in the first week, when numerous positive cells were present throughout the cortical layers; at P10, GAT-3-positive cells became less numerous and GAT-3 ir switched to the adult pattern, which was expressed at P20. Confocal and electron microscopic investigations showed that GAT-3 positive cells were both neurons and astrocytes. The present evidence indicates that early in development GAT-3 is abundantly expressed in the cerebral cortex, where its expression appears to correlate with developmental variations in GABA levels, and suggests that it accounts for the largest fraction of GABA transport observed in the neonatal cerebral cortex
Electron microscopy localization of NCX1, 2, 3 isoform protein exchangers in neuronal astrocytes.
No full textNa
+
/Ca
2+
exchangers (NCX1, 2 and 3) play relevant role in neural cells, where variations of cytosolic Ca
2+
concentration represent
a pivotal event in many physiological and pathological processes. Astrocytes display a type of excitability based on changes in
intracellular Ca
2+
concentration.
In the present study, electron microscopic immunohistochemistry was applied to investigate the expression of the three NCX1-3
protein isoforms, in astrocytes of cerebral cortex and hippocampus. Results showed that a conspicuous population of astrocytic
cells expressed NCX1–3 in both brain areas. Immunolabeling for NCX1-3 was observed in many glial profiles of various size,
notably in distal astrocytic processes in contiguity of synaptic structures, suggesting the involvement of NCX in shaping astrocytic [Ca]i transients evoked by adjacent synaptic activity. NCX1-3 immunoreactivities (irs) were expressed in astrocytic mitochondria, indicating an important contribution to mitochondrial Ca
2+
regulation in this cell type in situ. In addition, all NCX isoforms were consistently expressed in perivascular astrocytic endfeet, suggesting an important role in regulating the barrier function of blood-brain barrier (BBB). Present immunomorphological work showed that in both brain regions all NCX isoforms were
expressed in astrocytes, thus pointing to a widespread role of the three exchangers in maintaining Ca
2+
homeostasis in glial cells
and suggesting that distinct NCX isoforms may share analogous physiological roles in the brain in vivo
Thalamic connections of the second somatic sensory area in cats studied with anterograde and retrograde tract-tracing techniques.
No full textCellular localization and laminar distribution of AMPA glutamate receptor subunits mRNAs and proteins in the rat cerebral cortex.
No full textGABA transporters in the mammalian cerebral cortex: localization, development and pathological implications
No full textThe extracellular levels of γ-aminobutyric acid (GABA), the main inhibitory neurotransmitter in the mammalian cerebral cortex, are regulated by specific high-affinity, Na+/Cl- dependent transporters. Four distinct genes encoding GABA transporters (GATs), named GAT-1, GAT-2, GAT-3, and BGT-1 have been identified using molecular cloning. Of these, GAT-1 and -3 are expressed in the cerebral cortex. Studies of the cortical distribution, cellular localization, ontogeny and relationships of GATs with GABA-releasing elements using a variety of light and electron microscopic immunocytochemical techniques have shown that: (i) a fraction of GATs is strategically placed to mediate GABA uptake at fast inhibitory synapses, terminating GABA's action and shaping inhibitory postsynaptic responses; (ii) another fraction may participate in functions such as the regulation of GABA's diffusion to neighboring synapses and of GABA levels in cerebrospinal fluid; (iii) GATs may play a role in the complex processes regulating cortical maturation; and (iv) GATs may contribute to the dysregulation of neuronal excitability that accompanies at least two major human diseases: epilepsy and ischemia
Dietary supplementation with α-tocopherol reduces neuroinflammation and neuronal degeneration in the rat brain after kainic acid-induced status epilepticus
No full textCommissural connections of the cat periaqueductal gray matter studied with anterograde and retrograde tract-tracing techniques.
No full text- …
