Action of Enzymatic Inhibitors (Potassium Cyanide and Sodium Fluoride) on Muscle Fibre Sensitivity to Potassium Ion

Nature ◽  
1964 ◽  
Vol 204 (4958) ◽  
pp. 586-587 ◽  
Author(s):  
GUILLAUME VALETTE ◽  
KEMAL OZAN
1970 ◽  
Vol 131 (4) ◽  
pp. 727-743 ◽  
Author(s):  
James J. Nordlund ◽  
Richard K. Root ◽  
Sheldon M. Wolff

Release of the protein molecule, leukocytic pyrogen, is one of the many reactions exhibited by leukocytes after phagocytosis. After the ingestion of heat-killed S. albus, a 3–4 hr latent period exists, during which human peripheral leukocytes release no pyrogen, yet cellular metabolism is altered in such a way that pyrogen output may subsequently occur in the absence of further phagocytosis. Transcription of messenger RNA and translation of new protein are initial events in the. activation process, since addition of the inhibitors, actinomycin D, and cycloheximide or puromycin, during this period markedly depressed or abolished subsequent pyrogen release. These effects were noted to be dependent upon the time of addition of the inhibitors. None of the inhibitor drugs interfered with cell viability as measured by phagocytosis and hexose monophosphate shunt activity, nor did they alter the pyrogenicity of preformed leukocytic pyrogen. Vincristine did not inhibit pyrogen formation, consistent with its reported failure to alter RNA synthesis in mature human granulocytes. The glycolytic inhibitor, sodium fluoride, blocked pyrogen release both when added prior to particle ingestion or 1 hr after the initiation of phagocytosis. Whereas inhibition of phagocytosis would explain the sodium fluoride effect prior to 1 hr, this was not observed in leukocyte preparations incubated for 1 hr with S. albus before adding sodium fluoride. When sodium fluoride was added to preparations 2 hr after the start of incubation, the LP production was unimpaired. Potassium cyanide had no effect on cell activation or pyrogen release. These findings suggest that the primary energy supply for the activation process is derived from high energy phosphate bonds provided by anaerobic glycolysis. Since the major amount of cell activation appears to occur in the 1st hr after phagocytosis, this energy might be involved in the induction of a genome leading to the transcription of m-RNA and its translation into new protein or is required for polysome integrity during protein synthesis. It is suggested that this new protein may be leukocytic pyrogen itself, or an enzyme responsible for cleaving it from an inactive precursor.


1957 ◽  
Vol 3 (3) ◽  
pp. 363-380 ◽  
Author(s):  
B. A. Kihlman

The finding of Lilly and Thoday that potassium cyanide produces structural chromosome changes in root tips of Vicia faba was confirmed. Like mustards, diepoxides, and maleic hydrazide, potassium cyanide seems to act on cells at early interphase. A tendency of cyanide breaks to be concentrated in heterochromatic segments of the chromosomes was evident. The production of chromosome aberrations by cyanide proved to be practically unaffected by the temperature during treatment. In agreement with Lilly and Thoday, the effect of potassium cyanide was found to be dependent on oxygen tension during treatment. The effect of potassium cyanide increases with increasing oxygen concentration up to 100 per cent oxygen. In the absence of oxygen, potassium cyanide was not completely inactive, but produced a low, though significant frequency of aberrations. Pretreatments with 2.4-dinitrophenol did not influence the effect of potassium cyanide. When bean roots were treated with potassium cyanide before a treatment with 8-ethoxycaffeine, or at the same time as they were treated with 8-ethoxycaffeine, the effect of 8-ethoxycaffeine was almost completely suppressed. The effects of a number of other heavy metal complexing agents were also tested. Sodium fluoride, potassium thiocyanate, carbon monoxide, o-phenanthroline, 2.2-bipyridine, and sodium azide were without radiomimetic effect under the conditions employed, and so was a mixture of sodium azide and sodium fluoride. A low, but quite significant, radiomimetic effect was obtained after treatments with sodium diethyldithiocarbamate, cupferron, and 8-hydroxyquinoline. Under anaerobic conditions, the effects of cyanide and cupferron were both quantitatively and qualitatively indistinguishable. Unlike the effect of cyanide, the effect of cupferron was not enhanced by the presence of oxygen. The effects of the same heavy metal complexing agents were tested on the activities of the enzymes catalase and peroxidase. The activities of both of these enzymes were found to be totally inhibited only by potassium cyanide. In the other cases, little correlation was found between ability to inhibit the activities of these enzymes and ability to produce chromosome aberrations. In a number of experiments, hydrogen peroxide was found to be without radiomimetic effect, whether alone or in combination with potassium cyanide. t-Butyl hydroperoxide proved to be active. The effect of t-butyl hydroperoxide was substantially increased by pretreatments with 2.4.-dinitrophenol. The results are discussed, and it is concluded that the observations made do not support the hypothesis that hydrogen peroxide is involved in the production of chromosome aberrations by potassium cyanide. The possibility that organic peroxides are involved cannot be excluded on the bases of the experimental results. As an alternative hypothesis, it is suggested that iron or other heavy metals are present in the chromosomes and that cyanide and other heavy metal complexing agents produce chromosome aberrations by reacting with these metals.


1953 ◽  
Vol 51 (2) ◽  
pp. 215-224 ◽  
Author(s):  
J. Gordon ◽  
R. A. Hall ◽  
L. H. Stickland

1. The lysis ofBact. coliby glycine is inhibited completely by various treatments: (a) by heating the bacteria at 65 or 100° C.; (b) by the action of Cr, Fe, and Al salts at concentrations which cause agglutination of the organisms, (c) by various heavy metals, including particularly Hg and Ag salts, at low concentrations (d) by lethal concentrations of formaldehyde and phenol.2. The lysis is not inhibited by sodium fluoride, potassium cyanide, or sodium monoiodoacetate at concentrations which suppress the action of certain enzymes.3. This evidence on the whole supports the rejection of the view that a simple physical process is responsible for lysis by glycine, but does not yet enable us to distinguish between the other possible mechanisms of the lysis because the treatments used might equally interfere either with the structural proteins of the bacteria, or with the hypothetical enzymes which might be concerned in producing the lysis.


1945 ◽  
Vol 21 (3-4) ◽  
pp. 151-154
Author(s):  
T. YAO

1. The induction ability of the hypostome of Pelmatohydra oligactis is not drastically modified by respiratory stimulants or inhibitors such as methylene blue, potassium cyanide, lithium chloride and sodium fluoride, under experimental conditions. 2. A pretreatment with methylene blue may confer induction power on the normally inactive subtentacular implant. 3. Induction does not seem to be closely linked to the cyanide-sensitive respiratory system. 4. Oxygen is possibly of secondary importance only in the initial act of induction. Its absence, however, inhibits the further development of an induced bud.


1973 ◽  
Vol 70 ◽  
pp. 918-922 ◽  
Author(s):  
R. K. Srivastava ◽  
V. K. Srivastava ◽  
M. N. Srivastava ◽  
B. B. L. Saxena

2020 ◽  
Vol 59 (06) ◽  
pp. 428-437
Author(s):  
Viktoria Dorau-Rutke ◽  
Kai Huang ◽  
Mathias Lukas ◽  
Marc O. Schulze ◽  
Christian Rosner ◽  
...  

Abstract Aim The aim of this study was to establish a data base for normal 18F-sodium fluoride (18F-NaF) bone uptake as a function of age, sex and circadian rhythm in mice. Methods In 12 female (F) and 12 male (M) C57BL/6N mice PET images were acquired 90 min after intravenous injection of 20 MBq 18F-NaF for 30 minutes. Each mouse was imaged in follow-up studies at 1, 3, 6, 13 and 21 months of age. In order to assess for physiologic changes related to circadian rhythm, animals were imaged during light (sleep phase) as well as during night conditions (awake phase). Bone uptake is described as the median percentage of the injected activity (%IA) and in relation to bone volume (%IA/ml). Results A significant smaller bone volume was found in F (1.79 ml) compared to M (1.99 ml; p < 0.001). In sex-pooled data, highest bone uptake occurred at an age of 1 month (61.1 %IA, 44.5 %IA/ml) with a significant reduction (p < 0.001) at age 3 months (43.6 %IA, 23.6 %IA/ml), followed by an increase between 13 (47.3 %IA, 24.5 %IA/ml) and 21 months (52.2 %IA, 28.1 %IA/ml). F had a significantly higher total uptake (F 48.2 %IA, M 43.8 %IA; p = 0.026) as well as a higher uptake per ml bone tissue (F 27.0 %IA/ml; M 22.4 %IA/ml; p < 0.001). A significant impact of circadian rhythm was only found for F at ages of 3 and 6 months with a higher uptake during the sleep phase. Conclusion Circadian rhythm had a significant impact on uptake only in F of 3 and 6 months. Regarding sex, F showed generally higher uptake rates than M. The highest uptake values were observed during bone growth at age 1 month in both sexes, a second uptake peak occurred in elderly F. Designing future bone uptake studies with M, attention must be paid to age only, while in F circadian rhythm and age must be taken into account.


Planta Medica ◽  
2015 ◽  
Vol 81 (16) ◽  
Author(s):  
A Vasas ◽  
P Orvos ◽  
L Tálosi ◽  
P Forgo ◽  
G Pinke ◽  
...  

1975 ◽  
Vol 34 (01) ◽  
pp. 042-049 ◽  
Author(s):  
Shuichi Hashimoto ◽  
Sachiko Shibata ◽  
Bokro Kobayashi

SummaryThe radioactive adenosine 3′,5′-monophosphate (cyclic AMP) level derived from 8-14C adenine in intact rabbit platelets decreased in the presence of mitochondrial inhibitor (potassium cyanide) or uncoupler (sodium azide), and markedly increased by the addition of NaF, monoiodoacetic acid (MIA), or 2-deoxy-D-glucose. The stimulative effect of the glycolytic inhibitors was distinctly enhanced by the simultaneous addition of sodium succinate. MIA did neither directly stimulate the adenyl cyclase activity nor inhibit the phosphodiesterase activity. These results suggest that cyclic AMP synthesis in platelets is closely linked to mitochondrial oxidative phosphorylation.


Author(s):  
А.С. Казицкая ◽  
Т.К. Ядыкина ◽  
М.С. Бугаева ◽  
А.Г. Жукова ◽  
Н.Н. Михайлова ◽  
...  

В условиях непрерывного воздействия неблагоприятных факторов окружающей и производственной среды на человека особую актуальность приобретает изучение механизмов, поддерживающих гомеостаз организма. Длительное поступление фторидов в организм приводит к формированию хронической фтористой интоксикации, патогенез которой вызывает многочисленные споры и дискуссии. До сих пор недостаточно внимания уделяется изучению висцеральной патологии, обусловленной нарушениями иммунного статуса в условиях воздействия на организм соединений фтора. Практически отсутствуют исследования по изучению иммунной реактивности, определяющей морфофункциональный характер ответной реакции печени на ранних стадиях развития фтористой интоксикации. Цель работы - изучение действий патофизиологических механизмов иммунной реактивности печени при субхроническом действии на организм соединений фтора. Методика. Опыты проведены на 210 лабораторных крысах-самцах массой 180-220 г., разделенных на 2 группы: контрольную (n=80) и группу животных с субхроническим действием фторида натрия (n=130). Экспериментальные животные в течение 12 нед имели свободный доступ к водному раствору фторида натрия (концентрация 10 мг/л, что составляет суточную дозу фтора 1,2 мг/кг массы тела). Для изучения иммунологических и биохимических показателей забирали кровь из хвостовой вены через 1, 3, 6, 9, 12 нед от начала эксперимента. Для оценки состояния гуморального звена иммунитета определяли уровень сывороточных иммуноглобулинов (IgA, IgG, IgM) иммуноферментным анализом с помощью наборов реактивов ЗАО «Вектор-Бест» (Новосибирск). Уровень сывороточных цитокинов: TNF-α, IL-1β, 2, 4, 6, 10 определяли на анализаторе Multiskan EX методом иммуноферментного анализа с использованием наборов «Вектор Бест» (Новосибирск). Подсчет общего количества лейкоцитов произведен классическим способом в камере Горяева, анализ лейкоцитарной формулы - в окрашенных мазках периферической крови. Метаболические изменения оценивали по активности ферментов в ткани печени: щелочной фосфатазы (ЩФ), аланин- и аспартатаминотрансфераз (АЛТ, АСТ), лактатдегидрогеназы (ЛДГ), гаммаглутамилтранспептидазы (γ-ГТ). Активность ферментов определяли унифицированными методами с помощью наборов реактивов ЗАО «Вектор-Бест» (Новосибирск) на фотометре PM-750 (Германия). Гистологические исследования печени осуществляли после декапитации крыс, проводимой под эфирным наркозом. Результаты. Показано, что субхроническое воздействие фторида натрия сопровождается формированием внутриклеточных и внутрисосудистых повреждений печени. Активация медиаторов воспаления и развитие иммунологических нарушений в динамике эксперимента способствуют формированию системной воспалительной реакции, которая приводит к появлению стойких морфологических нарушений в печени и изменению активности ферментов основных метаболических путей. Заключение. Полученные результаты могут быть использованы при разработке и проведении профилактических мероприятий в условиях воздействия на организм высоких концентраций фтора с последовательным применением детоксикационной, иммуномодуляторной и органопротекторной коррекции. Studying mechanisms, which maintain the body homeostasis, is particularly important in the conditions of continuous impact of adverse environmental and manufacturing factors. Long-term exposure to fluorides leads to chronic fluoric intoxication, the pathogenesis of which is a subject of multiple controversy and discussions. Not enough attention is still paid to elucidating the visceral pathology associated with fluorine-induced immune disorders. There are virtually no studies of immune reactions that define the morphofunctional nature of the liver response to early stages of fluoric intoxication. Aim. To study pathophysiological mechanisms of hepatic immune reactivity in subchronic exposure of the body to fluorine compounds. Methods. Experiments were performed on 210 male rats weighing 180-220 g. The animals were divided into two groups: 1) control (n=80) and 2) subchronic exposure to sodium fluoride (n=130). The rats had free access to a 10 mg/l aqueous solution of sodium fluoride (daily dose, 1.2 mg/kg body weight) for 12 weeks. Blood was withdrawn from the caudal vein at 1, 3, 6, 9, and 12 weeks of the experiment for immunological and biochemical tests. Histological study of the liver was performed after decapitation of rats under ether anesthesia. Results. The subchronic exposure to sodium fluoride was associated with intracellular and intravascular damage of the liver. Activation of inflammatory mediators and development of immunological disorders during the experiment contributed to a systemic inflammatory reaction, which resulted in persistent morphological injuries of the liver and changes in enzyme activities in major metabolic pathways. Conclusion. The study results can be used for development and implementation of preventive measures against the effects of high fluorine concentrations, which would include a successive use of detoxification, immunomodulation and organ protection.


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