(n.) An intensely poisonous alkaloid, extracted from aconite.
Example Sentences:
(1) The reduction in 5-HIAA was transient after potassium infusion, but outlasted the infusion of veratridine or aconitine by several hours.
(2) Aconitine potentiated the contractile response of the guinea-pig vas deferens and increased the tissue Na and Ca content.
(3) Tetrodotoxin-sensitive influx of [14C]guanidinium ion was stimulated by aconitine, veratridine, and batrachotoxin with a K0.5 of 7, 5 and 0.3 microM, respectively, the maximal influx being the same with all toxins.
(4) Suppression of aconitine-induced ventricular tachycardia in the dog with various doses of Bunaftine was attempted.
(5) Aconitine will induce arrhythmias after the fiber has been completely repolarized.
(6) Quinidine, but not propranolol, suppressed atrial arrhythmias produced by topical application of aconitine to the atrium, as well as the ventricular arrhythmias that developed approximately 20 hr following coronary artery ligation.
(7) The substance proved to be active in delaying the onset time of aconitine induced arrhythmias in guinea-pig atria.
(8) When aconitine was applied to two epicardial sites in dogs having quinidine-induced QT interval prolongation greater than 10%, torsades de pointes occurred in 80% of instances.
(9) With the former treatment, the off time constant of the charge movement (tau off Q) was unaffected but with aconitine treatment it was considerably increased although it remained smaller than tau off Na.
(10) Furthermore, an attempt is made to present a detailed analysis of permeability changes underlying normal pacemaker activity in Purkinje fibers as compared with the sinus node or with focal activity induced in myocardial fibers by different influences (aconitine, barium ions, stretch, and strong currents).
(11) The appearance of several forms of aconitine-induced arrhythmias was delayed after subacute treatment with carbon disulfide.
(12) The animal experiments revealed that the time of death due to aconitine was significantly delayed in proportion to the dose of TTX compared with the case for aconitine alone, and that the mortality of aconitine was lowered by TTX when the dose ratio of the two toxins was in a particular range.
(13) The nerve compound action potential was inhibited by hypaconitine (5 microM) and aconitine (2-10 microM), as well as by 1 microM tetrodotoxin (TTX).
(14) Atrial arrhythmias were induced in experiments on dogs by electrical stimulation or by local application of aconitine and methacholine to the atrium.
(15) A test for inhibition of mortality induced by intravenous injection of aconitine in rats is proposed as a particularly valid method, owing to its simplicity and degree of specificity, for inclusion among the preliminary screening tests for antiarrhythmic activity.
(16) Both, LG 6-101 and LG 6-102 showed strong antiarrhythmic effects against arrhythmias induced on the fifth day by infusion of aconitine (10 micrograms kg-1 min-1).
(17) When the nerve compound action potential was completely blocked by 2 microM aconitine, the muscle action potential was unaffected, although 1 microM TTX suppressed both potentials to the same degree.
(18) route proved to be more potent and longer-acting than disopyramide, propaphenone and mexiletine against supraventricular and ventricular arrhythmias induced by chloroform, aconitine, ouabain and halothane-adrenaline.
(19) The aim of the experiments was to examine, in vitro, the role of the enteric nervous system in the relationship between motor activity and transmural potential difference (PD) in the guinea pig jejunum and colon using the nerve blocking agents tetrodotoxin (TTX) and aconitine.
(20) Polyphloretinphosphate markedly reduced the improvement of aconitine arrhythmia by PGs, the decrease of the antidysrhythmic effects of arachidonic and linoleic acid was without statistical significance.
Alkaloid
Definition:
(a.) Alt. of Alkaloidal
(n.) An organic base, especially one of a class of substances occurring ready formed in the tissues of plants and the bodies of animals.
Example Sentences:
(1) Thus, alkaloid and insecticide modifications share many features but differ in how much the conducting properties of the pore are changed and whether the channel can close reversibly while the toxin remains bound.
(2) A clear structure-mutagenicity relationship was observed in a series of aporphine alkaloids (aporphine, dehydroaporphine, 7-oxoaporphine and 4,5-dioxoaporphine), and 10,11-non-substituted aporphines were suggested to exert their mutagenicity through metabolic activation of the 10,11 positions, possibly as the 10,11-epoxides.
(3) A radioactive, photoactive Vinca alkaloid, N-(p-azido-[3,5-3H]-benzoyl)-N'-beta-aminoethylvindesine [( 3H]NABV) with pharmacological and biological activities similar to vinblastine was synthesized and used to identify specific Vinca alkaloid macromolecular interactions in calf brain homogenate by photoaffinity labeling.
(4) The comparative metabolism of the pyrrolizidine alkaloid (PA) senecionine was studied in vitro in incubations of rat, guinea pig, cow, horse, and sheep hepatic microsomes.
(5) They also displayed negative correlation between activities of protein-inhibitors and the total content of protein and alkaloids.
(6) Methods have been reviewed for alkylating agents, platinum compounds, antitumour antibiotics, antimetabolites, alkaloids, suramin, 1-hydroxy-3-amino-propylidene-1,1-bisphosphonate and tamoxifen.
(7) The resistant strains exhibited cross resistance to anthracycline antibiotics, vinca alkaloids, actinomycin D, colchicine.
(8) In mice treated with cepharanthine (Cepha), a biscoclaurine alkaloid, the number of T cells was increased in the parathymic lymph nodes (PtLNs) which are considered to be the specialized lymph nodes in local differentiation of T cells.
(9) The alkaloid tubulosine inhibits the process of peptide chain elongation by eukaryotic polysomes by specifically preventing the elongation-factor-2-dependent step of translocation.
(10) Cultured roots of Stephania cepharantha, which are rich sources of bisbenzylisoquinoline alkaloids, were fed 14C-labelled tyrosine, tyramine or dopamine.
(11) As a possible mechanism underlying the alterations of DRP, the functional consequences of atrophic changes of primary central afferent terminals are being discussed in terms of the close correlation between structure and function and the possible inferences of the electrophysiological reaction to the therapeutic application of Vinca alkaloids in the iontophoretic treatment of chronic intractable pain.
(12) The poisonous principles in tansy ragwort are pyrrolizidine alkaloids, which cause gradual alteration and necrosis of liver cells with replacement by fibrous tissue.
(13) In this study, the roots of Tabernaemontana heyneana Wall were examined and the isolation and identification of additional indole alkaloids and some pharmacological properties of coronaridine are described.
(14) The area ratios of four alkaloids (tropacocaine, norcocaine, cis-cinnamoylcocaine, and trans-cinnamoylcocaine) to cocaine are calculated for each sample.
(15) The main drugs with specific action on migraine include ergot alkaloids (ergotamine, dihydroergotamine), agonists (sumatriptan) or partial agonists (methysergide) at a specific subtype of 5-HT1-like receptors, beta-adrenoceptor antagonists (propranolol, metoprolol), calcium antagonists (flunarizine) and anti-inflammatory agents (indomethacin).
(16) Effects of solution variables on the binding and self-association explain the wide variation of reported apparent binding constants for Vinca alkaloids to tubulin.
(17) The concomitance of five previously reported trans-2,5-dialkyl-pyrrolidines along with small amounts of the cis isomers and N-methyl analogues makes the venom of M. indicum the most qualitatively diverse blend of alkaloids reported from an ant to date.
(18) Strong enhancement of delayed-type hypersensitivity (DTH) was observed after treatment with the active cyclophosphamide (CY) derivative Z 7557 or the plant alkaloid VP-16 at the site of sensitization.
(19) A total alkaloid and two purified alkaloid extracts of Alangium Vitiense were revealed by our experimental screening to be oncostatic on L1210 leukemia and two other lymphoid neoplasias in Mice.
(20) Possible mechanisms underlying these effects of insecticides on alkaloid-dependent uptake are discussed in light of a qualitative model formulated from these results and previous biochemical and electrophysiological studies.