(n.) One who contends for the prize in public games.
Example Sentences:
(1) alpha 1-Adrenergic agonists, phenylephrine and norfenefrine, did not affect the synthesis.
(2) Data obtained with fenoldopam were corroborated with use of SK&F 38393, another dopamine D1-receptor agonist.
(3) The GABA receptor agonist progabide reduced VCMs and locomotor activity.
(4) This novel mechanism of receptor regulation, named transmodulation, should be distinguished from the reduction in total receptor number caused by the homologous ligand (downregulation) and from the change in affinity produced by the binding of agonists or antagonists to the same receptor site.
(5) Exposure to nanomolar concentrations of saralasin, an Ang II agonist, attenuated the passage of the fluorophores across the monolayers by 50-75%.
(6) The effects of low doses of dihydropyridine (DHP) calcium channel antagonists nimodipine, nifedipine, (-)-R-202-791, and amlodipine, the DHP calcium channel agonist BAY K 8644 were investigated on clonic convulsions to pentylenetetrazole (PTZ) in mice.
(7) The binding to DNA-cellulose of heat-activated [3H]RU486-receptor complexes was slightly decreased (37%) when compared with that of the agonist [3H]R5020-receptor complexes (47%).
(8) These later results suggest that dopamine agonists increase sensorimotor reactivity measured with acoustic startle by acting on sensory rather than motor parts of the reflex arc.
(9) Only methoxyindole acetic acid was detectable after incubation of unstimulated and alpha-adrenergic-agonist-treated pineal glands.
(10) It inhibits platelet and vascular smooth muscle activation by cGMP-dependent attenuation of the agonist-induced rise of intracellular free Ca2+.
(11) The elimination half-life of most beta-agonists is relatively short, and pharmacokinetics are independent of dose and duration of treatment.
(12) Substance P (SP), a relatively non-selective tachykinin receptor agonist, and Septide and Senktide, highly selective NK-1 and NK-3 tachykinin receptor agonists, respectively, were injected intradermally in rats.
(13) Responses of control tissues to an alpha agonist (norepinephrine) were increased at lower temperatures and responses to a beta agonist (isoprenaline) were increased at higher temperatures.
(14) The inhibition of all three agonist responses by 1.1 mM calcium was competitive.
(15) The alpha 2 agonist, clonidine, produced a larger dose-related increase in food intake in lean rats than in the fatty rats.
(16) This stimulation is mediated by one receptor with an apparent affinity of 3.3 X 10(-6) M. The hydroxyl group in the para position on phenylethanolamine was absolutely necessary to obtain an agonist whereas the meta hydroxyl group or the presence of a catechol almost suppressed the activity.
(17) The alpha 2-adrenoceptor agonist clonidine is most potent for stimulating Isc.
(18) Moreover, the ribosylation inhibitors converted the glucocorticoid antagonist RU-486 into a potent agonist for cytolysis of L1210 cells.
(19) We have characterized the effects of adenosine, the A1-receptor agonist N6-(L-2-phenylisopropyl)-adenosine (PIA) and the A2-receptor agonist 5'-(N-ethyl)-carboxamido-adenosine (NECA), in isolated human pulmonary vessels.
(20) Long-term treatment with agents that stimulate the beta-receptor (prenalterol and pirbuterol) has not proved to be useful in the treatment of chronic heart failure; moreover, prolonged treatment with beta-agonists (dobutamine and pirbuterol) may adversely affect survival.
Antagonist
Definition:
(n.) One who contends with another, especially in combat; an adversary; an opponent.
(n.) A muscle which acts in opposition to another; as a flexor, which bends a part, is the antagonist of an extensor, which extends it.
(n.) A medicine which opposes the action of another medicine or of a poison when absorbed into the blood or tissues.
(a.) Antagonistic; opposing; counteracting; as, antagonist schools of philosophy.
Example Sentences:
(1) This death is also dependent on the presence of chloride and is prevented with the non-selective EAA antagonist, kynurenic acid, but is not prevented by QA.
(2) Microionophoretically applied excitatory amino acids induced firing of extracellularly recorded single units in a tissue slice preparation of the mouse cochlear nucleus, and the similarly applied antagonist 2-amino-5-phosphonovalerate (2APV) was demonstrated to be a selective N-methyl-D-aspartate (NMDA) receptor antagonist.
(3) Meanwhile the efficiency of muscarinic antagonists in inhibition of tremor reaction induced by arecoline administration is associated with interaction between the drugs and the M2-subtype.
(4) The anticonvulsant properties of the endogenous excitatory amino acid antagonist, kynurenic acid (KYA), were studied in prepubescent and adult rats using the amygdaloid kindling model of epilepsy.
(5) A novel bicyclic prostaglandin analogue, (1S)-[1 alpha,2 alpha(Z),3 alpha,4 alpha]-7-[3-[(hexylthio)methyl]-7- oxabicyclo [2.2.1]hept-2-yl]-5-heptenoic acid ((-)-10), and its cogeners were found to be potent antagonists at the TxA2 receptor.
(6) This difference was abolished by exposure of the slices to propranolol, a beta-adrenergic receptor antagonist.
(7) The TxA2 antagonistic effects of KW-3635 were compared with that of daltroban in PRP from various animals species.
(8) In experiments performed to determine whether PtdIns(4,5)P2 hydrolysis induced by TRH may have been caused by the elevation of [Ca2+]i, the following results were obtained: the effect of TRH to decrease the level of PtdIns(4,5)P2 was not reproduced by the calcium ionophore A23187 or by membrane depolarization with 50 mM K+; the calcium antagonist TMB-8 did not inhibit the TRH-induced decrease in PtdIns(4,5)P2; and, most importantly, inhibition by EGTA of the elevation of [Ca2+]i did not inhibit the TRH-induced decrease in PtdIns(4,5)P2.
(9) Similarly, 50 microM D-600, a Ca+2 channel antagonist, significantly (P less than 0.01) reduced basal and 5-HETE-induced PRL release.
(10) Selective removal of endothelium had no effect on BK-induced contraction or the action of the antagonists.
(11) The second experiments entailed use of the nonspecific opiate antagonist, naloxone, as well as the specific delta antagonist, ICI 154,129, against seizures induced by icv-administered morphine, morphiceptin, DADL, or DSLET.
(12) These antagonists reverse NMDA-mediated long term influence in these brain areas.
(13) This novel mechanism of receptor regulation, named transmodulation, should be distinguished from the reduction in total receptor number caused by the homologous ligand (downregulation) and from the change in affinity produced by the binding of agonists or antagonists to the same receptor site.
(14) Furthermore, the ability of a vasopressin antagonist to lower arterial pressure in NTS hypertensive rats was markedly attenuated by clonidine treatment.
(15) All of the serotonergic antagonists studied had additional effects on the response of the coronary artery to electrical stimulation or to norepinephrine.
(16) Their receptive fields comprise a temporally and spatially linear mechanism (center plus antagonistic surround) that responds to relatively low spatial frequency stimuli, and a temporally nonlinear mechanism, coextensive with the linear mechanism, that--though broad in extent--responds best to high spatial-frequency stimuli.
(17) The effects of low doses of dihydropyridine (DHP) calcium channel antagonists nimodipine, nifedipine, (-)-R-202-791, and amlodipine, the DHP calcium channel agonist BAY K 8644 were investigated on clonic convulsions to pentylenetetrazole (PTZ) in mice.
(18) Addition in the cultures of 4-deoxypyridoxine, a potent antagonist of vitamin B6 coenzymes, concurrently with the mitogen, inhibits the induction of serine hydroxymethyltransferase.
(19) These results suggest that prevention of xenograft rejection using PAF-antagonist in association with other methods should be further investigated.
(20) The high concentrations of gonadotropins present in immature female rats by the end of the second week of life were suppressed by treatment with an antagonist against luteinizing hormone-releasing hormone (LHRH-A; Org.