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1.
D. C. Morley  Jr  P. R. Galbraith 《CMAJ》1978,118(3):288-290
Lithium carbonate therapy is associated with polymorphonuclear leukocytosis. In vitro studies have shown that lithium ions stimulate formation of granulocytic colonies. In a study undertaken to determine how lithium acts, colony-forming cells uncontaminated by monocytes (which elaborate colony-stimulating factor [CSF] in vitro) were obtained by means of a two-step cell separation procedure. The effects of lithium on colony formation were then studied in (a) cultures stimulated by humoral CSF, (b) cultures in which monocytes were relied upon to synthesize CSF de novo and (c) unstimulated cultures. Lithium enhanced the action of CSF but did not stimulate colony formation in the absence of CSF. In monocyte-stimulated cultures, colony formation increased with lithium concentrations up to 1 mmol/L but this increase paralleled that in CSF-stimulated cultures and therefore was not due to increased CSF production by monocytes. At higher concentrations of lithium, colony formation decreased in the monocyte-stimulated cultures but increased in the CSF-stimulated cultures. A lithium concentration of 4 mmol/L gave the greatest enhancing effect on colony formation in CSF-stimulated cultures and a concentration greater than 1 mmol/L inhibited de novo synthesis of CSF by monocytes.  相似文献   

2.
Abstract— The effects of lithium chloride in vitro and in vivo were investigated on Na-K ATPase and Mg ATPase activities in synaptic plasma membrane, mitochondrial and synaptic vesicle fractions prepared from rat brain. In vitro , lithium chloride (10−3-10−8 m ) had no effect on ATPase activity in any of the fractions studied. Lithium chloride given chronically by i.p. injection (30 mg/rat/day) for 9 days had little effect on synaptic plasma membrane ATPases. Dietary administration of lithium chloride (60 mmol/kg food) produced a small but significant increase in synaptic plasma membrane Mg ATPase activity after 3 weeks administration and mitochondrial Mg ATPase activity after 1 week. There was no effect on synaptic plasma membrane Na-K ATPase activity. Salt supplementation reduced the toxic effects of lithium administration and it is suggested that toxicity may account for some of the previously reported changes in synaptic membrane ATPases produced by lithium.  相似文献   

3.
Abstract— The relationship between isotopic sodium entry into cerebrospinal fluid (CSF) from blood and cisternal potassium concentration was studied using ventriculo-cisternal perfusion in the rabbit. The entry of sodium into CSF was separated into 2 components. The fast component was significantly correlated with cisternal potassium concentration during perfusions with a potassium-free artificial CSF. ATPase activity in the homogenised choroid plexus was shown to be sensitive to potassium over a range of concentrations similar to that in the perfusion studies. The results are interpreted as showing a potassium-sensitive entry of 24Na across the choroid plexus due to a sodium-pump situated in the apical membrane of the choroid plexus. The effects of low concentrations of lithium (0.6–1.2 mm) on 24Na entry into CSF and brain and on CSF secretion were studied. When applied via the ventricles lithium caused a 30–39% stimulation of the fast component of sodium entry and a 28% stimulation of CSF secretion. When given via the blood lithium inhibited the fast component of sodium entry and CSF secretion by 43% and 40% respectively. No effects of lithium were found on the slow component of sodium entry into CSF or sodium entry into brain. The results suggest that lithium at low (0.6–1.2 mM) concentrations can stimulate the choroid plexus sodium-pump at the potassium-sensitive side and inhibit it at the sodium-sensitive side.  相似文献   

4.
唐丽 《激光生物学报》2003,12(4):264-268
目的:研究氯化锂(LiCl)在体外对KT—1/A3白血病细胞增殖及凋亡的影响。方法:采用液体培养实验,MTT实验,集落培养实验为指标观察LiCl对KT—1/A3细胞增殖的影响,采用DNA片段凝胶电泳及流式细胞检测为指标检测细胞凋亡。结果:①不同浓度的LiCl(5mM—25mM)对KT—1/A3细胞具有抑制增殖的作用,这种增殖抑制作用呈剂量依赖关系。②在LiCl(20mM)作用72h的DNA凝胶电泳谱可见DNA Ladder及流式细胞仪检测可见凋亡特有的AP峰,提示LiCl可诱导KT—1/A3细胞凋亡。绪论:LiCl能抑制KT—1/A3白血病细胞增殖和诱导凋亡。  相似文献   

5.
Direct measurement of uptake of sodium at the outer surface of the frog skin   总被引:15,自引:8,他引:7  
A combination of the methods described by Schultz et al. (6) and by Ussing and Zerahn (9) was used to measure directly the unidirectional uptake of sodium from the outside solution into the frog skin, under short-circuit conditions. The sodium uptake was determined at six sodium concentrations ranging from 3.4 to 114 mM. NaCl was replaced by choline chloride in the solutions bathing both sides of the skin. Sodium uptake is not a linear function of sodium concentration but appears to be composed of two components, a saturating one and one that varies linearly with concentration. The sodium uptake is inhibited by the addition of lithium to the outside solution. The effect appears to be primarily on the saturating component and has the characteristics of competitive inhibition. In addition, lithium uptake by the skin is inhibited by sodium. The effects of lithium cannot be ascribed to changes in electrical potential difference. Measurements with microelectrodes indicate that under short-circuit condition there is no change in the intracellular potential when lithium chloride is added to the outside solution.  相似文献   

6.
The effects of lithium chloride (LiCl) on differentiation of mouse embryonic stem (ES) cells were investigated in order to evaluate the ES cell test (EST) used in a European Union validation study for screening of embryotoxic agents in vitro. We show that LiCl inhibited concentration-dependently the differentiation of ES cells into cardiac and myogenic cells. Whereas the inhibition of cardiac differentiation by high concentrations of LiCl was obvious at day 5 + 5, decreased skeletal muscle cell differentiation was observed only at day 5 + 8. Semi-quantitative RT-PCR analyses revealed significantly lower levels of mRNA encoding cardiac-specific alpha-myosin heavy chain and skeletal muscle-specific myoD. By morphological investigation, an influence of lithium on neuronal differentiation was not evident. However, mRNA levels of genes encoding synaptophysin and the 160 kDa neurofilament protein were increased by high LiCl concentrations, whereas mRNA levels of mash-1 and Engrailed-1 were decreased, suggesting a specific influence of lithium on neuronal differentiation. Furthermore, LiCl treatment resulted in a slight, but non-significant increase of beta-catenin levels in ES cell-derived embryoid bodies. Our results demonstrate that the ES cell test, EST may be suitable to detect inhibitory effects of test compounds especially on cardiac differentiation, whereas effects on neuronal cells would not be detected. Therefore, we propose that morphological analyses of cardiac differentiation alone are insufficient to detect embryotoxic effects. The assay of other cell lineages at different developmental stages, and expression analyses of tissue-specific genes should also be employed.  相似文献   

7.
It has been proposed that an increase in CSF osmolality could be involved in the genesis of hypertension by activation of central nervous system receptors involved in cardiovascular regulation. ACTH induced hypertension in the sheep is an adrenally dependent model of steroid induced hypertension. This study reports the effect of ACTH administration (20 g/kg/day) for 5 days on the composition of cerebrospinal fluid (CSF) and blood (plasma) in conscious sheep. ACTH increased CSF and plasma osmolality within 24 h associated with parallel increases in both blood and CSF glucose concentrations and plasma and CSF sodium concentration. Plasma potassium fell within 24 h, but CSF potassium did not change over the 5 days of ACTH treatment. Neither calcium nor magnesium changed in either plasma or CSF. CSF phosphate increased and plasma phosphate decreased. CSF and plasma bicarbonate were elevated with ACTH. Plasma chloride decreased after 5 days of ACTH treatment but was not associated with a change in CSF. The relevance of the measured changes in CSF osmolality and composition to the mechanisms involved in the production of ACTH-induced hypertension will be subject of further experimentation.  相似文献   

8.
The objective of this study was to clarify the relationship between the effect and associated mechanisms of lithium chloride on neural stem cells (NSCs) and the Wnt signaling pathway. The expression of key molecules proteins related to the Wnt signaling pathway in the proliferation and differentiation of control NSCs and lithium chloride-treated NSCs was detected by Western blot analysis. Flow cytometry analysis was applied to study the cell cycle dynamics of control NSCs and NSCs treated with lithium chloride. The therapeutic concentrations of lithium chloride stimulated NSC proliferation. β-catenin expression gradually decreased, while Gsk-3β expression gradually increased (P?P?in vitro and preventing the cells from differentiating, which is potentially mediated by activation of the Wnt signaling pathway.  相似文献   

9.
The development of the chloride ion, glucose and total protein concentration was investigated in the cerebrospinal fluid of 11- to 21-day-old chick embryos and compared with their development in the blood plasma. Developmental changes in the chloride concentration in the plasma and CSF were very small, but it was always higher in the CSF than in the plasma. The plasma/CSF ratio fell during development, from 0.906 in 11-day-old embryos to 0.778 at the end of incubation. The CSF glucose concentration fell up to the 19th day of incubation, but a significant increase was recorded shortly before hatching. The plasma glucose concentration rose throughout the whole of the investigated period of embryogenesis. Up to the 19th day the P/CSF ratio rose from 1.59 to 4.05 and in 21-day-old embryos fell to 2.47. The developmental increase in the plasma total protein concentration was accompanied by the reverse process in the CSF. During the second half of incubation the P/CSF ratio rose from 1.88 to 7.9 Calculation of total osmolarity from the Na+, K+, Ca2+, Cl- and glucose concentration showed permanent hyperosmolarity of the CSF compared with the plasma. The P/CSF ratio was maintained within limits of 0.94 to 0.98.  相似文献   

10.
Cell kinetics of lithium-induced granulopoiesis   总被引:1,自引:0,他引:1  
Abstract. Lithium has been shown to be an effective inducer of granulopoiesis. The mechanism of lithium action has been shown to influence CFU-s and CFU-c proliferation, increase colony-stimulating factor (CSF) production and reduce erythropoiesis. We report here evidence to show that lithium recruits CFU-c that are not normally in the cell cycle into active DNA synthesis, as measured by hydroxyurea and tritiated thymidine suicide techniques. Furthermore, lithium action is shown to be time-dependent, since the delay addition of lithium for 5 min to normal bone marrow removes the enhancement usually seen when lithium is given at time zero. The implications of these lithium-induced effects are described.  相似文献   

11.
Abstract— In monkeys we measured the steady-state concentrations of Cl in endogenous CSF, in artificial CSF (which had equilibrated with the underlying exposed surface of the cerebral cortex but was not in diffusion equilibrium with endogenous CSF), and in arterial plasma. The ratio of the distribution of Cl in artificial CSF to that in plasma was consistent with a passive Donnan distribution, whereas that ratio describing Cl levels in endogenous CSF in comparison to those in plasma clearly exceeded theratio required for a passive, Donnantype of distribution for Cl. The kinetic analysis of the efflux of Cl from blood into endogenous CSF and into artificial CSF (perfused over the exposed surface of the cerebral cortex) indicated that the rate of efflux of Cl into endogenous CSF which was continuous with ventricular fluid was inhibited by acetazolamide [in confirmation of a similar finding described previously by M aren and B roder (1970)], whereas the rate of efflux of chloride from blood into the artificial CSF perfusate was uninfluenced by pretreatment of animals with acetazolamide. We have discussed the site of mediated (active) transport of chloride from blood into CSF in light of these findings.  相似文献   

12.
Spherical formations of the plague microbe strains from the Transcaucasian Upland, I plague microbe strain of the sandwort variety and I strain of the marmot variety were obtained under the effect of lithium chloride. They had the remains of the cell wall, were viable, sensitive to osmotic shock, preserved sensitivity to the specific bacteriophage and pesticins. All this was evident of isolation of the spheroplasts of the plague microbe. The spheroplasts showed a capacity for pesticin production. The pesticin synthesis by the spheroplasts of the plague causative agent from the Transcaucasian Upland increased with an increase in the content of lithium chloride in the medium. The largest inhibiiton zones were observed, when 0.7-0.8 per cent of lithium chloride were present in the medium. In the spheroplasts of the plague causative agent from the Mountain Altai (the marmot variety) the pesticin synthesis was inhibited with an increase in the content of lithium chloride in the medium. The activity spectrum of the pesticins of the spheroplasts of the plague causative agent from the Transcaucasian Upland and the spheroplasts of the strains of the marmot and sandwort varieties was broader than that of the rod-like forms of these strains. The indicator properties were found in the strains of the plague microbe of the marmot and sandwort varieties with respect to the pesticins of the spheroplasts of the sel-like producing organisms and organisms from the Transcaucasian Upland.  相似文献   

13.
Sodium butyrate, lithium acetate, and hydroxyurea given to serum-free culture of RSP-2 X P3 cells notably reduced the rate of cell proliferation but markedly enhanced the production of such a colony-stimulating factor (CSF) as one that stimulated predominantly neutrophilic granulocyte colony formation in mouse bone marrow cell cultures (Tsuneoka and Shikita, 1984). On the other hand, the production of macrophage CSF was not increased in the butyrate-treated RSP-2 X 3 cells. Butyrate also failed to enhance either macrophage CSF or neutrophil CSF production in L X P3 (mouse fibroblast line), Huk-1 X P3 (human kidney cell line) or Nil2C2 (hamster embryo fibroblast line) cells. The addition of bacterial lipopolysaccharide (LPS) together with butyrate resulted in further pronounced enhancement of the neutrophil CSF production in RSP-2 X P3 cells, while the cells did not develop tolerance against LPS upon repeated challenge. The yield of neutrophil CSF was thus increased by about 45 times that of the control during continuous culture for 12 days. Large-scale culture of the cells under these conditions must be an excellent source of a CSF for neutrophil granulocytes.  相似文献   

14.
We aimed to observe the therapeutic effects of lithium on inhalational anesthetic sevoflurane-induced apoptosis in immature brain hippocampus. From postnatal day 5 (P5) to P28, male Sprague–Dawley pups were intraperitoneally injected with lithium chloride or 0.9 % sodium chloride. On P7 after the injection, pups were exposed to 2.3 % sevoflurane or air for 6 h. Brain tissues were harvested 12 h and 3 weeks after exposure. Cleaved caspase-3, nNOS protein, GSK-3β,p-GSK-3β were assessed by Western blot, and histopathological changes were assessed using Nissl stain and TUNEL stain. From P28, we used the eight-arm radial maze test and step-through test to evaluate the influence of sevoflurane exposure on the learning and memory of juvenile rats. The results showed that neonatal sevoflurane exposure induced caspase-3 activation and histopathological changes in hippocampus can be attenuated by lithium chloride. Sevoflurane increased GSK-3β activity while pretreatment of lithium decreased GSK-3β activity. Moreover, sevoflurane showed possibly slight but temporal influence on the spatial learning and the memory of juvenile rats, and chronic use of lithium chloride might have the therapeutic effect. Our current study suggests that lithium attenuates sevoflurane induced neonatal hippocampual damage by GSK-3β pathway and might improve learning and memory deficits in rats after neonatal exposure.  相似文献   

15.
Abstract: Mild depolarisation (20 m M KCI) synergistically enhances the ability of a muscarinic agonist to activate phosphoinositide turnover and to elevate inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] in cerebellar granule cells in primary culture. The effects of lithium on this intense stimulation of phosphoinositide turnover was studied. Lithium causes depletion of cytoplasmic inositol and phosphoinositides, which results in the inhibition of phosphoinositide turnover within 15 min and the return of Ins(1,4,5)P3 to basal levels at this time. This inhibition could not be reversed by culturing and preincubating cerebellar granule cells in concentrations of inositol similar to those detected in the CSF. Inositol concentrations substantially in excess of those in the CSF not only reversed the effects of lithium on stimulated Ins(1,4,5)P3 levels, but significantly enhanced this level in comparison with stimulation in the absence of lithium. sn -1,2-Diacylglycerol elevation during stimulated phosphoinositide turnover was also disrupted by lithium, but in contrast to Ins(1,4,5)3, the presence of lithium resulted in a transient enhancement of the elevation evoked by carbachol plus mild KCI depolarisation, which was reversed by 500 µ M inositol, but not by 200 µ M inositol. The implications of these phenomena in relation to the mechanism of action of lithium in the treatment of manic depression are discussed.  相似文献   

16.
Tumor promoting phorbol esters, such as 12-0-tetradecanoyl-phorbol-13-acetate (TPA), stimulate colony formation in vitro by murine granulocyte-macrophage progenitors (GM-CFC) without added colony stimulating factors (CSF). To determine whether TPA induces CSF production in vitro, marrow cells were cultured for 1 to 7 days in liquid medium with or without TPA. No CSF was detected in any sample by a double antibody radioimmunoassay (sensitivity = 2 units/0.1 ml), however, colony-stimulating activity was detected in supernatant fluid from all TPA containing cultures by bioassay. This activity appeared to result from a direct effect of TPA rather than from production of CSF, as equivalent activity was found in TPA-containing medium incubated in the absence of marrow cells. Rabbit antiserum to purified L-cell CSF inhibited colony formation stimulated by L-cell CSF and WEHI-3 CSF, but had no effect on colony formation induced by TPA. Cells from long-term marrow cultures responded to TPA with colony formation, despite culture conditions and cell fractionation procedures that reduced the frequency of CSF-producing macrophages to less than 1.0%. TPA inhibited binding of radioiodinated L-cell CSF to marrow cells, especially if the cells were first exposed to TPA. These results do not support induction of CSF production as the major mechanism of phorbol ester stimulation of myelopoiesis. Phorbol esters may directly stimulate GM-CFC and/or enhance their response to CSF by a mechanism involving CSF binding sites.  相似文献   

17.
The gene encoding isocitrate dehydrogenase (IDH) is somatically mutated predominantly in secondary glioblastoma multiforme. Mutations of IDH1 and IDH2 lead to simultaneous loss and gain of activities in the production of α-ketoglutarate and 2-hydroxyglutarate, respectively. Lithium chloride was recently proved efficient in inhibiting glioma cell migration. The mechanism of lithium chloride on C6 glioma cells harboring IDH2 mutation has not been studied. Here, we found lithium chloride induced inhibitive effects on cell proliferation of both C6 glioma cells with and without IDH2 mutation, although IDH2 mutation increased the stability of HIF-1α. GSK-3β could be phosphorylated at Ser9 and its activity was inhibited when C6 glioma cells were treated by lithium chloride. The degree of phosphorylation in IDH2R172G treatment group was lower than that as compared to the control and IDH2 treatment groups. At the same time, the accumulation of β-catenin in C6 cell nucleus was decreased. Moreover, although the β-catenin and HIF-1α increased the secretion of metalloproteinase-2,-9 in C6 glioma cells harboring IDH2 mutation, the migration potential of lithium chloride-treated C6 glioma cells harboring the IDH2 and its mutant was uniform. These results indicated lithium chloride could decrease the proliferation and migration potential of C6 glioma cells harboring IDH2 mutation.  相似文献   

18.
The phycobilisomes (PBS) from the blue-green algae Microcystis aerogenosa was found to possess the adenylate kinase activity. The enzyme activity of PBS is kept for 2 weeks, reaching its maximum on th 2nd-4th day after PBS isolation from the cells, and is retained after passage of freshly isolated PBS through a column with Sephadex G-25. The adenylate kinase activity of PBS is thermostable, depends on the protein concentration in the sample, undergoes activation by white light and is inhibited by glutaric aldehyde. The enzyme activity is presumably determined by the components of the low molecular weight protein fraction of non-pigment origin, which are constituents of PBS.  相似文献   

19.
The purpose of the present study was to examine the effects of lithium, a drug which is now used rather widely in the treatment of acute mania and the prophylaxis of manic-depressive bipolar disorders, on the pituitary-gonadal function in the laboratory rat. Sexually adult male rats, maintained under standardized laboratory conditions (LD 14: 10; lights on at 06:00 h, CST), were injected (ip) with lithium chloride both acutely for 1 day and chronically for 5 days, and by utilizing a low and high dose. For the low dose, lithium was injected twice daily (at 10:00 and 15:00 h) at 2.5 meg/Kg for 1 and 5 days, whereas in the high dose groups, also receiving lithium twice daily and at the same hours, the dosages were 5 meq/Kg for 1 day and 3.5 meq/Kg for 5 days. Animals were sacrificed 4 hours after the last lithium (or saline) injections. Plasma and pituitary levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH), and plasma levels of testosterone (T) were measured by radioimmunoassay (RIA). The administration of the low dose led to a significantly higher (P less than 0.001) plasma FSH, but unaltered plasma LH, levels after 5 days. In contrast, the high dose lithium led to significant suppressions of plasma LH (P less than 0.02; on day 5) and FSH (P less than 0.001; on both day 1 and 5) levels. The levels of plasma T also showed a significant reduction following the low dose (P less than 0.02; on day 5), as well as the high dose lithium treatment, as evident after both 1 (P less than 0.02) and 5 (P less than 0.02) days. Regardless of the dosage, or the duration of treatment, pituitary gonadotropin levels remained unaltered following lithium. The results of our present experiments suggest that lithium administration, either acutely or on a chronic basis, might be associated with significant adverse effects on the pituitary-testicular axis. Furthermore, since some of the hormonal changes were evident when plasma lithium concentration was within the therapeutic range, our data may have potential clinical implications.  相似文献   

20.
myo-Inositol-1-phosphatase has been partially purified from bovine brain. The enzyme has a molecular weight of about 58,000. Both L-myo-inositol 1-phosphate and D-myo-inositol 1-phosphate are hydrolyzed by the enzyme as well as (-)-chiro-inositol 3-phosphate and 2'-AMP. Triphosphoinositide is not a substrate. The phosphatase is completely dependent on Mg2+, which has a Km of 1 mM. Calcium and manganese ions are competitive inhibitors of Mg2+ binding with Ki values of 18 microM and 2 microM, respectively. Lithium chloride inhibits the hydrolysis of both L- and D-myo-inositol 1-phosphate to the extent of 50% at a concentration of 0.8 mM. The phosphatase from testis is similarly inhibited by lithium. Lithium ion is a noncompetitive inhibitor of Mg2+ binding and an uncompetitive inhibitor of myo-inositol 1-phosphate binding. Because lithium chloride administration elicits both an increase in the levels of myo-inositol 1-phosphate and a decrease in the levels of myo-inositol in rat brain (Allison, 1978), and because these actions are blocked by anticholinergic agents, we examined the effects of cholinergic agonists and antagonists on the enzyme and found none. The possibility that the inhibition of this enzyme by lithium ion is related to the pharmacological actions of lithium is discussed.  相似文献   

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