Search results for "TRP"

Role of endocannabinoids and TRPV1 channels in the bioelectric activity of hippocampal neurons

It has been reported that endocannabinoid system is an important player in the regulation of neuronal bioelectrical activity, relying on receptor-mediated mechanisms. Amongst these, Cannabinoid receptor type 1 (CB1r) and Transient Receptor Potential Vanilloid type 1 (TRPV1) are both modulated by endocannabinoids, involved in the transduction of stimuli in the pre-synaptic neuron and prompt downstream pathways in the post-synaptic neuron. To investigate the role of CB1r/TRPV1 interplay, we applied whole-cell patch clamp technique to visualize the eventual variations in terms of membrane current and action potentials induced by pharmacological manipulation in rat hippocampal neurons. We modul…

Electrocatalysis of neurotransmitter catecholamines by 2,4,6-triphenylpyrylium ion immobilized inside zeolite Y supercages

1999

2,4,6-Triphenylpyrylium ions entrapped inside the supercages of Y zeolite exert a remarkable catalytic effect toward the electrochemical oxidation of dopamine and norepinephrine (neurotrasmitter catecholamines) in neutral aqueous media. Domenech Carbo, Antonio, Antonio.Domenech@uv.es

'TRPing' synaptic ribbon function in the rat pineal gland: neuroendocrine regulation involves the capsaicin receptor TRPV1.

2009

Synaptic ribbons (SRs) are presynaptic structures thought to regulate and facilitate multivesicular release. In the pineal gland, they display a circadian rhythm with higher levels at night paralleling melatonin synthesis. To gain more insight into the processes involved and the possible functions of these structures, a series of experiments were conducted in rodents. We studied the regional distribution of a molecular marker of pineal SRs, the kinesin motor KIF3A in the gland. Respective immunoreactivity was abundant in central regions of the gland where sympathetic fibers were less dense, and vice versa, revealing that intercellular communication between adjacent pinealocytes is enhanced …

La Bourgogne a-t-elle vocation à devenir un entrepôt de la métropole parisienne ?

2016

International audience

New hyaluronic acid based brush copolymers synthesized by atom transfer radical polymerization

2013

Glucose excites hypothalamic neurons through the activation of Transient Receptor Potential Canonical (TRPC) channels

2015

International audience

Systematic Study of a Library of PDMAEMA-Based, Superparamagnetic Nano-Stars for the Transfection of CHO-K1 Cells.

2017

The introduction of the DNA into mammalian cells remains a challenge in gene delivery, particularly in vivo. Viral vectors are unmatched in their efficiency for gene delivery, but may trigger immune responses and cause severe side-reactions. Non-viral vectors are much less efficient. Recently, our group has suggested that a star-shaped structure improves and even transforms the gene delivery capability of synthetic polycations. In this contribution, this effect was systematically studied using a library of highly homogeneous, paramagnetic nano-star polycations with varied arm lengths and grafting densities. Gene delivery was conducted in CHO-K1 cells, using a plasmid encoding a green fluore…

Proton conductance of human transient receptor potential-vanilloid type-1 expressed in oocytes of Xenopus laevis and in Chinese hamster ovary cells.

2004

Transient receptor potential-vanilloid type-1 (TRPV1) is a ligand-gated cation channel with preference for divalent cations, especially Ca(2+) (sequence of conductances: Ca(2+)Mg(2+)Na(+) approximately/= K(+) approximately/= Cs(+)). In the present study, the two-electrode voltage-clamp technique was used on oocytes of Xenopus laevis expressing TRPV1 to evaluate whether human TRPV1 also conducts protons. In medium devoid of K(+), Na(+), Mg(2+), and Ca(2+), capsaicin 1 microM induced a significant inward current (62% of the current in physiological medium). The effects of capsaicin were abolished in the presence of capsazepine 3 microM. The capsaicin-induced currents in medium devoid of Na(+)…

The identification of peroxisome proliferator-activated receptor alpha-independent effects of oleoylethanolamide on intestinal transit in mice

2009

Oleoylethanolamide (OEA) is an endogenous lipid produced in the intestine that mediates satiety by activation of peroxisome proliferator-activated receptor alpha (PPARalpha). OEA inhibits gastric emptying and intestinal motility, but the mechanism of action remains to be determined. We investigated whether OEA inhibits intestinal motility by activation of PPARalpha. PPARalpha immunoreactivity was examined in whole mount preparations of mouse gastrointestinal (GI) tract. The effect of OEA on motility was assessed in wildtype, PPARalpha, cannabinoid CB(1) receptor and CB(2) receptor gene-deficient mice and in a model of accelerated GI transit. In addition, the effect of OEA on motility was as…

Activation of Astrocytes in the Persistence of Post-hypoxic Respiratory Augmentation

2021

Acute hypoxia increases ventilation. After cessation of hypoxia loading, ventilation decreases but remains above the pre-exposure baseline level for a time. However, the mechanism of this post-hypoxic persistent respiratory augmentation (PHRA), which is a short-term potentiation of breathing, has not been elucidated. We aimed to test the hypothesis that astrocytes are involved in PHRA. To this end, we investigated hypoxic ventilatory responses by whole-body plethysmography in unanesthetized adult mice. The animals breathed room air, hypoxic gas mixture (7% O2, 93% N2) for 2min, and again room air for 10min before and after i.p. administration of low (100mg/kg) and high (300mg/kg) doses of a…