Search results for "Cholin"
showing 10 items of 1261 documents
A Trisialoganglioside Containing a Sialyl α2-6 N-Acetylgalactosamine Residue Is a Cholinergic-Specific Antigen, Chol-1α1
1992
Cholinergic-specific antigens termed the Chol-1 family have been suggested to be of a ganglioside nature by Richardson et al. (J. Neurochem. 38, 1605-1614, 1982). Two molecular species of polysialogangliosides among bovine brain gangliosides were found to react with anti-Chol-1 alpha antiserum. One of them, Chol-1 alpha-a, was isolated and characterized as a trisialoganglioside containing the gangliotetraose backbone in which 1 mol of sialic acid was attached to each of the reducing end galactose, N-acetylgalactosamine and internal galactose residues, respectively. The chemical structure of Chol-1 alpha-a was determined for the first time, being as follows: IV3NeuAc III6NeuAc II3NeuAc-GgOse…
Opposite vascular activity of (R)-apomorphine and its oxidised derivatives. Endothelium-dependent vasoconstriction induced by the auto-oxidation meta…
2003
We have synthetised a series of oxidised apomorphine derivatives (orto and para quinones 2-5), in order to analyse their vascular activity. We have performed radioligand binding assays on rat cortical membranes and functional studies on rat aortic rings. Instead the relaxant activity exhibited by (R)-apomorphine, o-quinones 2, 4, show contractile activity dependent on endothelium in rat aortic rings. Compound 2, the main metabolite of (R)-apomorphine auto-oxidation, was the product which showed enhanced contractile activity by a complex mechanism related to activation of Ca(2+) channels through release and/or inhibition of endothelial factors. Moreover, this compound disrupts the endothelia…
Lateral organization of G M1 in phase-separated monolayers visualized by scanning force microscopy
2002
Phase separation of glycolipids in lipid mono- and bilayers is of great interest for the understanding of membrane function. The distribution of the ganglioside GM1 in sphingomyelin (SM)/1-palmitoyl-2-oleoyl- sn-glycero-3-phosphocholine (POPC), SM/1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DOPC) and SM/cholesterol/POPC Langmuir-Blodgett (LB) monolayers transferred at 36 mN/m has been studied by scanning force microscopy. Besides lateral organization of the glycolipid in LB monolayers as deduced from topography, material properties have been investigated by phase imaging, pulsed force mode and force modulation microscopy. It was shown that GM1 preferentially clusters in an ordered lipid m…
Enhanced ion transfer rate due to the presence of zwitterionic phospholipid monolayers at the ITIES
2000
Abstract The transfer of cations across phospholipid monolayers at ITIES is studied both experimentally and theoretically. Further evidence of the enhanced rate for cation transfer due to the presence of the monolayer is presented, and a theoretical model that can explain these observations is worked out. The system considered experimentally is Li + ion transfer across a hemispherical water ∣ 1,2-dichloroethane interface covered by distearoyl phosphatidylcholine. The theoretical description is based on the electrical double layer correction to the Butler–Volmer equation, coupled with a solution of the Poisson–Boltzmann equation across the interfacial region. The phospholipid monolayer is mo…
A Methanol Extract ofBrugmansia arboreaAffects the Reinforcing and Motor Effects of Morphine and Cocaine in Mice
2013
Previous reports have shown that several of the effects of morphine, including the development of tolerance and physical withdrawal symptoms, are reduced by extracts ofBrugmansia arborea(L.) Lagerheim (Solanaceae) (B. arborea). In the present study we evaluate the action of the methanol extract ofB. arborea(7.5–60 mg/kg) on the motor and reinforcing effects of morphine (20 and 40 mg/kg) and cocaine (25 mg/kg) using the conditioned place preference (CPP) procedure. At the doses employed,B. arboreadid not affect motor activity or induce any effect on CPP. The extract partially counteracted morphine-induced motor activity and completely blocked the CPP induced by 20 mg/kg morphine. On the othe…
A filtering algorithm for maneuvering target tracking based on smoothing spline fitting
2014
Published version of an article in the journal: Abstract and Applied Analysis. Also available from the publisher at: http://dx.doi.org/10.1155/2014/127643 Open Access Maneuvering target tracking is a challenge. Target's sudden speed or direction changing would make the common filtering tracker divergence. To improve the accuracy of maneuvering target tracking, we propose a tracking algorithm based on spline fitting. Curve fitting, based on historical point trace, reflects the mobility information. The innovation of this paper is assuming that there is no dynamic motion model, and prediction is only based on the curve fitting over the measured data. Monte Carlo simulation results show that, …
On the geographical distribution of pseudocholinesterase variants.
1975
The incidence of pseudocholinesterase (PCHE equals E.C. 3.1.1.8) variants in samples of 8 different population (total of 2218 individuals) is reported. Together with previously mentioned data from the literature, a general survey on the geographical distribution of PCHE isoenzymes is given. Possible reasons for present-day heterogeneity of their distribution are also discussed. Concerning the incidence of the C5 variant, it is pointed out that the validity of applying population genetic models depends upon the accuracy of the genetic basis.
Role for NK1 and NK2 receptors in the motor activity in mouse colon
2007
The present study examined the effects induced by endogenous and exogenous activation of NK(1) and NK(2) receptors on the mechanical activity of mouse proximal colon. Experiments were performed in vitro recording the changes in intraluminal pressure from isolated colonic segments. Electrical field stimulation in the presence of atropine and guanethidine produced a small relaxation, followed by nonadrenergic noncholinergic (NANC) contraction. SR140333, NK(1) receptor antagonist, or SR48968, NK(2) receptor antagonist, significantly reduced the contraction, although SR48968 appeared more efficacious. The co-administration of SR140333 and SR48968 virtually abolished the NANC contraction. [Sar(9…
Effects of Atropine on Acetylcholine Overflow from Perfused Chicken Hearts
1978
Isolated chicken hearts were perfused (20 ml/min) with Tyrode’s solution. Release of acetylcholine (ACh) was evoked either by electrical stimulation (1 ms; 15 mA) of both preganglionic vagus nerves or by perfusion with dimethylphenylpiperazinium (DMPP). ACh was extracted from the perfusates by ion-pair extraction and determined by gas chromatography.
EMG activity of pigeon oesophagus in vivo.
1982
At rest, the pigeon cervical oesophagus, which is entirely smooth muscle, shows electric activity. This activity consists of bursts of spikes with frequency increasing in the oral-aboral direction. The bursts are un-phase locked, and there are no slow waves (E.C.A.). The surgical transection of the oesophageal muscular wall does not affect the electric activity even in a disconnected segment. After asphyxia electric activity persists, whereas the aboral gradient of frequency disappears. Therefore, the electric activity is thought to be myogenic in origin, and the frequency gradient nervous in origin. Atropine and neostigmine administration suggests that the cholinergic system modulates the …