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Involvement of tachykinin NK2 receptors in the modulation of spontaneous motility in rat proximal colon.
2000
The role of endogenous tachykinins and the mechanisms whereby they act on NK2 receptors, modulating spontaneous motility, were investigated in rat isolated proximal colon. The mechanical activity was detected as changes in intraluminal pressure. The NK2 receptor antagonist, MEN 10627, produced a concentration-dependent reduction of the contraction amplitude. [beta-Ala8]-neurokinin A(4-10), an NK2 receptor agonist, and [Sar9, Met(O2)11]-Substance P ([Sar9, Met(O2)11]-SP), an NK1 receptor agonist, induced a concentration-dependent contractile response, characterized by an increase in basal tone with superimposed phasic contractions. MEN 10627 antagonized the response to [beta-Ala8]-neurokinin…
The 5-HT and alpha-adrenoceptor antagonist effect of four benzylisoquinoline alkaloids on rat aorta.
1998
Abstract The action of four benzylisoquinoline alkaloids (two aporphines—glaucine and apomorphine, a benzylisoquinoline—papaverine and a bisbenzyltetrahydroisoquinoline—antioquine) on 5-HT-induced contraction in rat thoracic aorta has been examined and compared with that of the control drugs: ketanserin, nifedipine, prazosin and phentolamine. The relaxant action on 5-HT-induced contraction was contrasted with that on the contraction induced by noradrenaline and KCl. The results obtained with control drugs show that ketanserin has clear selectivity for 5-HT receptors, whereas prazosin and phentolamine have high selectivity for the α1-adrenoceptor and nifedipine seems to have a more potent ef…
Low-dose dopamine agonist administration blocks vascular endothelial growth factor (VEGF)-mediated vascular hyperpermeability without altering VEGF r…
2006
No specific treatment is available for ovarian hyperstimulation syndrome (OHSS), the most important complication in infertile women treated with gonadotropins. OHSS is caused by increased vascular permeability (VP) through ovarian hypersecretion of vascular endothelial growth factor (VEGF)activating VEGF receptor 2 (VEGFR-2). We previously demonstrated in an OHSS rodent model that increased VP was prevented by inactivating VEGFR-2 with a receptor antagonist(SU5416).However,duetoitstoxicity(thromboembolism) and disruption of VEGFR-2-dependent angiogenic processes critical for pregnancy, this kind of compound cannot be used clinically to prevent OHSS. Dopamine receptor 2 (Dp-r2) agonists, use…
Exposure to gp120 of HIV-1 induces an increased release of arachidonic acid in rat primary neuronal cell culture followed by NMDA receptor-mediated n…
1995
After incubation of highly enriched neurons from rat cerebral cortex with the HIV-1 coat protein gp120 for 18 h, cells showed fragmentation of DNA at internucleosomal linkers followed by NMDA receptor-mediated neurotoxicity. We report that in response to exposure to gp120 cells react with an increased release of arachidonic acid (AA) via activation of phospholipase A2. This process was not inhibited by NMDA receptor antagonists. To investigate the role of AA on the sensitivity of the NMDA receptor towards its agonist, low concentrations of NMDA were co-administered with AA. This condition enhanced the NMDA-mediated cytotoxicity. Administration of mepacrine reduced cytotoxicity caused by gp1…
ATP and endogenous agonists inhibit evoked [3H]-noradrenaline release in rat iris via A1 and P2y-like purinoceptors.
1993
Effects of ATP, adenosine and purinoceptor antagonists on field stimulation-evoked (3 Hz, 2 min) [3H]-noradrenaline overflow were investigated in the rat isolated iris. ATP and adenosine inhibited the evoked overflow of [3H]-noradrenaline. 1,3-Dipropyl-8-cyclopentylxanthine (DPCPX) shifted the concentration-response curve of ATP to the right in a concentration-dependent manner, but with a potency (-log KB = 7.88) much lower than expected for an A1 adenosine receptor. In the continuous presence of DPCPX, the ATP-induced prejunctional inhibition was unaffected by suramin (100 mumol/l) and DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, 50 mumol/l) but was antagonized by the P2Y-rece…
Ontogenetic and Pharmacological Studies on Metabotropic Glutamate Receptors Coupled to Phospholipase D Activation
1997
The present study was aimed at characterizing the metabotropic receptor subtype which is involved in the activation of phospholipase D (PLD) by glutamate in rat hippocampal slices. We first observed that the ontogenetic profile of glutamate-induced hydrolysis of phosphoinositides and of phosphatidylcholine was strikingly similar. Both pathways were significantly activated by glutamate in tissue taken from 3-, 8- and 15-day old rats, but not in adult rats. PLD activation was strongest in slices taken from 8-day old rats. At this age, quisqualate had a higher potency for PLD activation (EC50: 0.6 microM) than 1S,3R-ACPD (EC50: 16 microM) and DHPG, a specific activator of group I mGluR, was a …
¿Están los rasgos de personalidad asociados al bienestar psicológico?
2019
espanolExiste poca informacion de como los rasgos de personalidad puede afectar al bienestar psicologico. Los estudios senalan que el neuroticismo y la extraversion son los rasgos que mayor vinculacion poseen con el bienestar psicologico. En este estudio se investigo como los rasgos de personalidad se asocian a las seis dimensiones del bienestar psicologico en una muestra de adultos mayores espanoles. La muestra estuvo compuesta por 224 adultos mayores a los que se aplicaron las escalas de bienestar psicologico y el cuestionario NEO-FFI. Se analizaron los resultados mediante regresion lineal multiple. Se obtuvieron asocia-ciones significativas en todas las dimensiones del bienestar psicolog…
Effect of a Brassica Juncea Cover Crop on a Mono-Succession of Melon
2013
The ban of methyl bromide and the need for low environmental impact of agriculture has recently increased the interest in the biofumigant effects of Brassica species on soil-borne pathogens. Many researches have tested the toxic effects of Brassica green manures on several soil-borne pathogens in vitro, but field studies have not assessed definitely the efficiency of biofumigation at the field scale and the effect on crop development and production quality. The aim of this research was to evaluate the effect of a winter-spring cover crop of Brassica juncea compared to bare soil on a mono-succession of melon. The biomass of the B. juncea plants or of the weeds eventually developed in bare so…
Influence of the methodology of inoculation in the performance of air-breathing microbial fuel cells
2017
n this work, four air-breathing microbial fuel cells (AB-MFC) were operated for 1 month in order to determine if the methodology of inoculation affects the steady-state performance of this type of MFCs. For this purpose, anaerobic and aerobic sludge were fed to two identical AB-MFCs without any external carbon source into a tight sealed environment during the first three days of start-up. For comparison purposes, other two AB-MFCs were operated mixing the initial sludge and an amount of sodium acetate as substrate. Results point out that the inoculation procedure does not affect the steady-state treatment capacity of the cells but it affects very seriously the production of electricity. Onl…
Zvaigžņotā Debess: 2017, Pavasaris (235)
2017
Contents: “ZVAIGŽŅOTĀ DEBESS” FORTY YEARS AGO: E.Mūkins. Clouds of Venus: Structure and Composition (abridged) ; J.Miezis. 3rd All-union Young Astronomers Gathering (abridged) ; DEVELOPMENTS in SCIENCE: K.Schwartz. New Discoveries in the Milky Way ; DISCOVERIES: I.Eglītis. Small Planets Get Latvian Names ; I.Pundure. Earth-mass World Revealed around Proxima Centauri ; SPACE RESEARCH and EXPLORATION: J.Jaunbergs. Mysteries of Saturn’s Clouds ; A.Slavinskis. Contribution of Estonian Student Satellite Programme ESTCube to Largest Challenges for Humanity ; R.Misa. Impossible Engine that Is likely Possible ; I.Pundure. ESO VLT to Search for Planets in Alpha Centauri System ; EARTH and COSMOS: J.…