Search results for "Synaptic potential"
showing 7 items of 377 documents
Oncostatin M, leukaemia-inhibitory factor and interleukin 6 trigger different effects on alpha1-proteinase inhibitor synthesis in human lung-derived …
1998
Interleukin 6 (IL-6), oncostatin M (OSM) and leukaemia-inhibitory factor (LIF) share a common signal-transducing subunit in each of their receptors and thus mediate an overlapping spectrum of biological activities. Although all of these cytokines stimulate the production of α1-proteinase inhibitor (α1-PI) in hepatocyte-derived cells, only OSM is able to up-regulate levels of this inhibitor in epithelial cells originating from the lung. In this study we characterized human lung-derived epithelial-like HTB58 cells for their ability to synthesize α1-PI after treatment with IL-6, OSM and LIF. The results demonstrate that the resistance of HTB58 cells to the effects of IL-6 and LIF was not becau…
Inhibitory influences of vagal afferences on the oesophageal EMG peristaltic pattern
1987
AbstractThe influence of vagal afferents on the EMG peristaltic pattern was studied in pigeon oesophagus.Bilateral vagotomy did not abolish the primary peristalsis, but induced significant modifications of the peristaltic pattern parameters.Vagal afferent stimulation induced an inhibitory effect consisting of a temporary break or definitive block of the EMG peristaltic activity already in progress.Vagal afferent stimulation also induced a reduction of the spontaneous EMG activity and this effect was abolished either by glossopharyngeal bilateral section or ganglionic block.Likewise vagal afferent stimulation, the crop distension caused inhibitory effects on EMG peristaltic pattern. This eff…
Mechanical activity of small and large intestine in normal and mdx mice: a comparative analysis.
1999
The aim of this study was to compare the motor pattern (recorded as changes in intraluminal pressure) of isolated duodenum and proximal colon between dystrophic mdx and normal mice. When duodenal recordings from control preparations were compared with mdx mice there was no significant difference in the spontaneous motor pattern, responses to electrical nerve stimulation or sensitivity to pharmacological agents. Colonic segments from mdx mice showed a more complex motor pattern, consisting of contractions with amplitude and frequency similar to those of controls and by additional contractions with lower amplitude and higher frequency. Moreover, 70% of the colonic preparations from mdx mice d…
Duodenal contractile activity in dystrophic (mdx) mice: reduction of nitric oxide influence.
2003
The present study was undertaken to analyse duodenal contractility in adult dystrophic (mdx) mice. The spontaneous changes of the isometric tension and the responses of longitudinal duodenal muscle to nonadrenergic, noncholinergic (NANC) nerve stimulation and to exogenous drugs were compared between normal and mdx mice. Duodenal segments from mdx mice displayed spontaneous contractions with higher frequency than normals. N omega-nitro-L-arginine methyl ester (L-NAME) increased the frequency of contractions in normals without affecting that in mdx mice. In normals, NANC nerve stimulation elicited a transient relaxation abolished by L-NAME. In mdx mice a frank relaxation was not observed, the…
Enkephalin-containing interneurons are specialized to innervate other interneurons in the hippocampal CA1 region of the rat and guinea-pig
1998
Enkephalins are known to have a profound effect on hippocampal inhibition, but the possible endogenous source of these neuropeptides, and their relationship to inhibitory interneurons is still to be identified. In the present study we analysed the morphological characteristics of met-enkephalin-immunoreactive cells in the CA1 region of the rat and guinea-pig hippocampus, their coexistence with other neuronal markers and their target selectivity at the light and electron microscopic levels. Several interneurons in all subfields of the hippocampus were found to be immunoreactive for met-enkephalin. In the guinea-pig, fibres arising from immunoreactive interneurons were seen to form a plexus …
Parietal Cortex Connectivity as a Marker of Shift in Spatial Attention Following Continuous Theta Burst Stimulation
2021
Non-invasive brain stimulation is a useful tool to probe brain function and provide therapeutic treatments in disease. When applied to the right posterior parietal cortex (PPC) of healthy participants, it is possible to temporarily shift spatial attention and mimic symptoms of spatial neglect. However, the field of brain stimulation is plagued by issues of high response variability. The aim of this study was to investigate baseline functional connectivity as a predictor of response to an inhibitory brain stimulation paradigm applied to the right PPC. In fourteen healthy adults (9 female, aged 24.8 ± 4.0 years) we applied continuous theta burst stimulation (cTBS) to suppress activity in the …
(A,B) In vivo GCaMP6f signals recorded in layers M1, M5 and M9/10 of Mi1 (A) and Tm3 (B) neurons, before (blue, green) and after (gray, red) applicat…
2019
Sensory systems sequentially extract increasingly complex features. ON and OFF pathways, for example, encode increases or decreases of a stimulus from a common input. This ON/OFF pathway split is thought to occur at individual synaptic connections through a sign-inverting synapse in one of the pathways. Here, we show that ON selectivity is a multisynaptic process in the Drosophila visual system. A pharmacogenetics approach demonstrates that both glutamatergic inhibition through GluClα and GABAergic inhibition through Rdl mediate ON responses. Although neurons postsynaptic to the glutamatergic ON pathway input L1 lose all responses in GluClα mutants, they are resistant to a cell-type-specifi…