BACKGROUND AND PURPOSE
While arachidonyl ethanolamine (anandamide) produces pharmacological effects mediated by cannabinoid CB1 receptors, it is also an agonist at the transient receptor potential ...vanilloid type 1 (TRPV1) ion channel. This study examined the cellular actions of anandamide in the midbrain periaqueductal grey (PAG), a region implicated in the analgesic actions of cannabinoids, and which expresses both CB1 receptors and TRPV1.
EXPERIMENTAL APPROACH
In vitro
whole cell patch clamp recordings of glutamatergic excitatory postsynaptic currents (EPSCs) were made from rat and mouse PAG slices.
KEY RESULTS
Capsaicin (1 µM) increased the rate, but not the amplitude of miniature EPSCs in subpopulations of neurons throughout the rat and mouse PAG. Capsaicin had no effect on miniature EPSCs in PAG neurons from TRPV1 knock‐out mice. In mouse PAG neurons, anandamide (30 µM) had no effect on the rate of miniature EPSCs alone, or in the presence of either the CB1 antagonist AM251 (3 µM) or the TRPV1 antagonist iodoresiniferatoxin (300 nM). Anandamide produced a decrease in miniature EPSC rate in the presence of the fatty acid amide hydrolase (FAAH) inhibitor URB597 (1 µM). By contrast, anandamide produced an increase in miniature EPSC rate in the presence of both URB597 and AM251, which was absent in TRPV1 knock‐out mice.
CONCLUSIONS AND IMPLICATIONS
These results suggest that the actions of anandamide within PAG are limited by enzymatic degradation by FAAH. FAAH blockade unmasks both presynaptic inhibition and excitation of glutamatergic synaptic transmission which are mediated via CB1 receptors and TRPV1 respectively.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
A novel transmission system that adaptively compensates for intra- and inter-channel nonlinear distortions while alleviating the computation load is described. It does so by using an optical ...dispersion compensation at optical nodes and a Volterra-based multi-channel nonlinear equalisation. Simulation results show that 3.8 dB Q-factor improvements are obtained against conventional systems that do not compensate for nonlinear distortions.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract
Hypothetical short-range interactions could be detected by measuring the wavefunctions of gravitationally bound ultracold neutrons (UCNs) on a mirror in the Earth's gravitational field.
...Searches for them with higher sensitivity require detectors with higher spatial resolution.
We developed and have been improving an UCN detector with a high spatial resolution, which consists of a Si substrate, a thin converter layer including ^10B_4C, and a layer of fine-grained nuclear emulsion.
Its resolution was estimated to be less than 100 nm by fitting tracks of either ^7Li nuclei or α-particles, which were created when neutrons interacted with the ^10B_4C layer.
For actual measurements of the spatial distributions, the following two improvements were made.
The first improvement was to establish a method to align microscopic images with high accuracy within a wide region of 65 mm × 0.2 mm.
We created reference marks of 1 μm and 5 μm diameter with an interval of 50 μm and 500 μm, respectively, on the Si substrate by electron beam lithography and realized a position accuracy of less than 30 nm.
The second improvement was to build a holder for the detector that could maintain the atmospheric pressure around the nuclear emulsion to utilize it under a vacuum during exposure to UCNs.
The intrinsic resolution of the improved detector was estimated to be better than
0.56(8) μm by evaluating the blur of a transmission image of a gadolinium grating taken by cold neutrons.
The evaluation included the precision of the gadolinium grating.
A test exposure was conducted to obtain the spatial distribution of UCNs in the quantized states on a mirror in the Earth's gravitational field.
The distribution was obtained, fitted with the theoretical curve, and turned out to be reasonable for UCNs in quantized states when we considered a blurring of 6.9 μm.
The blurring was well explained as a result of neutron refraction due to the large surface roughness on the upstream side of the Si substrate.
By using a double-side-polished Si substrate, a resolution of less than 0.56 μm is expected to be achieved for UCNs.
Neurotensin modulates pain via its actions within descending analgesic pathways which include brain regions such as the midbrain
periaqueductal grey (PAG). The aim of this study was to examine the ...cellular actions of neurotensin on PAG neurons. Whole
cell patch clamp recordings were made from rat midbrain PAG slices in vitro to examine the postsynaptic effects of neurotensin and its effects on GABA A mediated inhibitory postsynaptic currents (IPSCs). Neurotensin (100â300 n m ) produced an inward current in subpopulations of opioid sensitive and insensitive PAG neurons which did not reverse over
membrane potentials between â50 and â130 mV. The neurotensin induced current was abolished by the NTS1 and NTS1/2 antagonists
SR48692 (300 n m ) and SR142948A (300 n m ). Neurotensin also produced a reduction in the amplitude of evoked IPSCs, but had no effect on the rate and amplitude of
TTX-resistant miniature IPSCs. The neurotensin induced inhibition of evoked IPSCs was reduced by the mGluR5 antagonist MPEP
(5μ m ) and abolished by the cannabinoid CB 1 receptor antagonist AM251 (3μ m ). These results suggest that neurotensin produces direct neuronal depolarisation via NTS1 receptors and inhibits GABAergic
synaptic transmission within the PAG. The inhibition of synaptic transmission is mediated by neuronal excitation and action
potential dependent release of glutamate, leading to mGluR5 mediated production of endocannabinoids which activate presynaptic
CB 1 receptors. Thus, neurotensin has cellular actions within the PAG which are consistent with both algesic and analgesic activity,
some of which are mediated via the endocannabinoid system.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We quantitatively estimate the effect of spontaneous Raman scattering on a quantum channel wavelength-multiplexed with a classical channel. Based on an experiment that measured the generation power ...of spontaneous Raman scattering in a fiber, the performance of wavelength-multiplexed quantum key distribution (QKD) systems using the differential-phase-shift protocol is evaluated for various system conditions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This paper reports the track multiplicity and kinematics of muons, charged pions, and protons from charged-current inclusive νμ and νμ interactions on a water target, measured using a nuclear ...emulsion detector in the NINJA experiment. A 3-kg water target was exposed to the T2K antineutrino-enhanced beam corresponding to 7.1 × 1020 protons on target with a mean energy of 1.3 GeV. Owing to the high granularity of the nuclear emulsion, protons with momenta down to 200 MeV=c from the neutrino-water interactions were detected. We find good agreement between the observed data and model predictions for all kinematic distributions other than the number of charged pions and the muon kinematics shapes. These results demonstrate the capability of measurements with nuclear emulsion to improve neutrino interaction models.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Background: Plaque erosion is a cause of atherothrombosis that preferentially occurs on smooth muscle cell (SMC)‐ and proteoglycan‐rich rather than lipid‐rich plaques. However, its underlying ...mechanisms remain unknown. Objective: To determine whether disturbed blood flow induces erosive injury and thrombus formation on SMC‐rich neointima. Methods: Three weeks after balloon injury, SMC‐rich neointima with increased tissue factor (TF) activity developed in rabbit femoral arteries that were narrowed with a vascular occluder to disturb blood flow after stenosis. Neointimal injury and thrombus formation were assessed at 15, 30, and 180 min after the vascular narrowing. Results: Endothelial detachment, platelet adhesion and neointimal cell apoptosis became evident at the post‐stenotic regions of all femoral arteries (n = 5) within 15 min of narrowing. Mural thrombi composed of platelet and fibrin developed after 30 min, and then occlusive thrombi were generated in three out of five vessels after 180 min. The identical vascular narrowing of normal femoral arteries also induced endothelial detachment with small platelet thrombi at post‐stenotic regions, but fibrin and occlusive thrombi did not develop. Computational simulation analysis indicated that oscillatory shear stress contributes to the development of erosive damage to the neointima. Conclusions: These results suggest that disturbed post‐stenotic blood flow can induce erosive injury in SMC‐rich plaques and promote thrombus formation that results in vascular events.
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FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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