(n.) A very poisonous alkaloid resembling brucine, obtained from various species of plants, especially from species of Loganiaceae, as from the seeds of the St. Ignatius bean (Strychnos Ignatia) and from nux vomica. It is obtained as a white crystalline substance, having a very bitter acrid taste, and is employed in medicine (chiefly in the form of the sulphate) as a powerful neurotic stimulant. Called also strychnia, and formerly strychnina.
Example Sentences:
(1) The in vitro metabolism of strychnine was studied in the 9000g supernatant fractions from rat and rabbit livers.
(2) 5 alpha-Pregnan-3 alpha-ol-20-one protected mice against metrazol-, bicuculline- and picrotoxin-induced seizures but not against electroshock-and strychnine-induced seizures.
(3) Pre-treatment with subconvulsive doses of strychnine, an antagonist of the neurotransmitter glycine, partially or completely blocked the inhibitory effects on phrenic activity of muscle-afferent stimulation.
(4) From a comparison of activation by strychnine and picrotoxin in normal and chronically decapitated embryos it was deduced that a spinal and a supraspinal component participated in their effect.
(5) Injections of glycine or strychnine (10--100 micrograms) into one SN induced slow ipsiversive or contraversive turning respectively.
(6) alpha-Bungarotoxin (10(-7) M), decamethonium (10(-5) M), d-tubocurarine (5 X 10(-5) M), and strychnine (5 X 10(-5) M) blocked the carbachol depolarization by about 90%.
(7) The action of strychnine and picrotoxin on the values of different reflex components was not identical; this pointed to a different localization of the inhibitory action of GABA and glycine in the central link of the somatosympathetic reflex arch.
(8) The inhibitory effect of bicuculline and strychnine was accompanied by vigorous convulsions.
(9) To determine whether the inhibitory neurotransmitter, glycine, contributes to the action of VS, strychnine, a specific glycine receptor antagonist was administered perispinally via intrathecal catheter in dosages of 1,5,25 and 100 micrograms.
(10) These findings demonstrate that strychnine-induced motor evoked potential changes arise from spinal gray activity induced by efferent pathways activated during transcortical stimulation.
(11) With strychnine, specific antagonist of glycine, excitation prevailed in EI, I and E neurons.
(12) While NAL and OXO did not alter the threshold for convulsions induced by PTZ, strychnine or picrotoxin, both agents lowered the threshold for electroshock-induced seizures.
(13) The intracisternal injection of HEPB or gamma-aminobutyric acid (GABA) in mice resulted in a potentiation of strychnine-induced convulsions.
(14) The effect of equimolar doses of glycine (G) and some related amino acids: beta-alanine (A), taurine (T) and betaine (B) on the strychnine syndrome was tested by administering them (intrathecal route) along with strychnine.
(15) MDL 27,531, which acts functionally like a glycine agonist in its capacity to selectively reverse seizures produced by the glycine antagonist strychnine, was evaluated in a model of spinal injury-induced reflex dysfunction.
(16) Strychnine blockade was also reversed by Cdp (10 micrometer).
(17) A focus of more powerful excitation created with the same strychnine played the role of determinant despatch station (DDS).
(18) The efflux of taurine was unaffected by strychnine, picrotoxin, tubocurarine, atropine, chlorpromazine, and 2-amino-4-phosphonobutyrate, whereas it was increased by glutamate diethyl esther and alpha-amino adipate.
(19) Some neurones failed to demonstrate this behaviour following the administration of strychnine.
(20) Strychnine improved the patient's motoricity presumably by blocking the excessive glycine-mediated inhibition of motoneurons.
Toxic
Definition:
(a.) Alt. of Toxical
Example Sentences:
(1) This suggested that the chemical effects produced by shock waves were either absent or attenuated in the cells, or were inherently less toxic than those of ionizing irradiation.
(2) Theophylline kinetics, as an in vivo probe for the potentially toxic cytochrome P-450I pathway of drug metabolism, were studied in 11 healthy volunteers and 11 patients with calcific chronic pancreatitis at Madras, South India.
(3) Treatment termination due to lack of efficacy or combined insufficient therapeutic response and toxicity proved to be influenced by the initial disease activity and by the rank order of prescription.
(4) Although Jeggo's Chinese hamster ovary cells were more responsive to mAMSA, novo still abrogated mAMSA toxicity in the mutant cells as well as in the parental Chinese hamster ovary cells 2,4-Dinitrophenol acted similarly to novo with respect to mAMSA killing, but neither compound reduced the ATP content of V79 cells.
(5) The pancreatic changes are unlikely to be an artefact, but rather a direct toxic effect of the alcohol as confirmed by the biochemical changes.
(6) Results suggest that Cd-MT is reabsorbed and broken down by kidney tubule cells in a physiological manner with possible subsequent release of the toxic cadmium ion.
(7) Previous studies have not evaluated the potential for oxygen toxicity at 9.5 psia.
(8) They more precisely delineate the hazard identification process and the factors important in supporting risk decisions for developmental toxicants than does any other document.
(9) Accidentally discovered nearly 40 years ago as the first true antidepressants, the MAOIs soon fell into disfavor due to concerns about toxicity and seemingly lesser efficacy compared with the newer tricyclic compounds.
(10) The results confirm studies performed in our laboratory on cytotoxicity and on functional membrane proteins of fungal and mammalian cells [1,2], suggesting a common mechanism of toxicity by the action of hydrophobic xenobiotics on biomembranes.
(11) testosterone, fentanyl, nicotine) may ultimately be administered in this way, important questions pertaining to pharmacology (tolerance), toxicity (irritation, sensitisation) and dose sufficiency (penetration enhancement) remain.
(12) None of the compounds proved active against the replication of retroviruses (human immunodeficiency virus, murine sarcoma virus) at concentrations that were not toxic to the host cells.
(13) It was shown that the antibiotic had low acute toxicity, did not cumulate and had no skin-irritating effect.
(14) Diminished CMD was most common with AR (7 of 12) but was also seen with acute tubular necrosis (2 of 6) and cyclosporin toxicity (2 of 3).
(15) Histopathological studies confirmed that mice fed 933cu-rev died from bilateral renal cortical tubular necrosis consistent with toxic insult, perhaps due to Shiga-like toxins.
(16) Research must continue to determine the optimal regimen that suppresses testosterone activity with the least amount of toxicity.
(17) In South Africa, health risks associated with exposure to toxic waste sites need to be viewed in the context of current community health concerns, competing causes of disease and ill-health, and the relative lack of knowledge about environmental contamination and associated health effects.
(18) Analysis of 156 records relating to patients at the age of 15 to 85 years with extended purulent peritonitis of the surgical and gynecological genesis (the toxic phase, VI category ASA) showed that combination of programmed sanitation laparotomy and intensive antibacterial therapy performed as short-term courses before, during and after the operation with an account of the information on the nature of the microbial associations and antibioticograms was an efficient procedure in treatment of severe peritonitis.
(19) Treatment was monitored by simple measurements, and it's toxicity proved to be scanty.
(20) And adding to this toxic mix, was the fear that the hung parliament would lead to a weak government.