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1.
Artigo em Inglês | MEDLINE | ID: mdl-26853524

RESUMO

We conducted a systematic review and meta-analysis to evaluate the effects of acupuncture on malignancy-related, chemotherapy (CT)- or radiation therapy (RT)-induced, surgery-induced, and hormone therapy (HT)-induced pain. Randomised controlled trials (RCTs) examining the effects of acupuncture on cancer-related pain were reached from the EMBASE, PubMed, PsycINFO, Cochrane Central Register of Controlled Trials, CINAHL, Airiti library, Taiwan Electrical Periodical Service, Wanfang Data (a Chinese database) and China Knowledge Resource Integrated Database from inception through June 2014. Heterogeneity, moderator analysis, publication bias and risk of bias associated with the included studies were examined. A total of 29 RCTs yielding 36 effect sizes were included. The overall effect of acupuncture on cancer-related pain was -0.45 [95% confidence interval (CI) = -0.63 to -0.26]. The subanalysis indicated that acupuncture relieved malignancy-related and surgery-induced pain [effect size (g) = -0.71, and -0.40; 95% CI = -0.94 to -0.48, and -0.69 to -0.10] but not CT- or RT-induced and HT-induced pain (g = -0.05, and -0.64, 95% CI = -0.33 to 0.24, and -1.55 to 0.27). Acupuncture is effective in relieving cancer-related pain, particularly malignancy-related and surgery-induced pain. Our findings suggest that acupuncture can be adopted as part of a multimodal approach for reducing cancer-related pain.


Assuntos
Terapia por Acupuntura/métodos , Dor do Câncer/terapia , Humanos
2.
Br J Dermatol ; 165(3): 633-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21668425

RESUMO

BACKGROUND: Pruritus is very common in uraemic patients, but the treatment remains challenging. Studies regarding narrowband ultraviolet B (NB-UVB) phototherapy for uraemic pruritus are rare. OBJECTIVES: To investigate whether or not NB-UVB phototherapy is an effective treatment for uraemic pruritus. METHODS: We conducted a single-blind, randomized, controlled trial for patients with refractory uraemic pruritus. The treatment group received NB-UVB phototherapy three times per week for 6 weeks. The dose of NB-UVB started from 210 mJ cm(-2) and was increased by 10% each time. The control group received time-matched exposures to long-wave UVA radiation. A visual analogue scale (VAS) score was evaluated weekly for pruritus intensity for 12 weeks. The characteristics of pruritus were also assessed by a questionnaire at baseline and after 6 weeks of phototherapy. RESULTS: Both the NB-UVB and control groups had significant and comparable improvement in the pruritus intensity VAS scores during the period of phototherapy and follow-up. Compared with the control group, the NB-UVB group showed a significant improvement in the involved body surface area affected by pruritus (P = 0·006), but not in sleep quality. More detailed regression and estimating analysis revealed that the patients in the NB-UVB group had lower pruritus intensity scores at week 6, week 10 and week 12. This may indicate a beneficial difference at certain time points, but the effect seems marginal. CONCLUSIONS: NB-UVB phototherapy does not show a significant effect in reducing pruritus intensity compared with a control group for refractory uraemic pruritus. Further studies are warranted.


Assuntos
Prurido/radioterapia , Terapia Ultravioleta/métodos , Uremia/complicações , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prurido/complicações , Método Simples-Cego , Resultado do Tratamento
3.
J Neuroendocrinol ; 22(8): 944-50, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20553372

RESUMO

Gonadotrophin-releasing hormone (GnRH) neurones control the onset and maintenance of fertility. Aberrant development of the GnRH system underlies infertility in Kallmann syndrome [KS; idiopathic hypogonadotropic hypogonadism (IHH) and anosmia]. Some KS patients harbour mutations in the fibroblast growth factor receptor 1 (Fgfr1) and Fgf8 genes. The biological significance of these two genes in GnRH neuronal development was corroborated by the observation that GnRH neurones were severely reduced in newborn transgenic mice deficient in either gene. In the present study, we hypothesised that the compound deficiency of Fgf8 and its cognate receptors, Fgfr1 and Fgfr3, may lead to more deleterious effects on the GnRH system, thereby resulting in a more severe reproductive phenotype in patients harbouring these mutations. This hypothesis was tested by counting the number of GnRH neurones in adult transgenic mice with digenic heterozygous mutations in Fgfr1/Fgf8, Fgfr3/Fgf8 or Fgfr1/Fgfr3. Monogenic heterozygous mutations in Fgfr1, Fgf8 or Fgfr3 caused a 30-50% decrease in the total number of GnRH neurones. Interestingly, mice with digenic mutations in Fgfr1/Fgf8 showed a greater decrease in GnRH neurones compared to mice with a heterozygous defect in the Fgfr1 or Fgf8 alone. This compounding effect was not detected in mice with digenic heterozygous mutations in Fgfr3/Fgf8 or Fgfr1/Fgfr3. These results support the hypothesis that IHH/KS patients with digenic mutations in Fgfr1/Fgf8 may have a further reduction in the GnRH neuronal population compared to patients harbouring monogenic haploid mutations in Fgfr1 or Fgf8. Because only Fgfr1/Fgf8 compound deficiency leads to greater GnRH system defect, this also suggests that these fibroblast growth factor signalling components interact in a highly specific fashion to support GnRH neuronal development.


Assuntos
Fator 8 de Crescimento de Fibroblasto/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/fisiologia , Animais , Fator 8 de Crescimento de Fibroblasto/genética , Humanos , Hipogonadismo/fisiopatologia , Hipotálamo/citologia , Hipotálamo/metabolismo , Síndrome de Kallmann/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/citologia , Neurônios/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética
4.
Br J Anaesth ; 104(1): 44-51, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19933511

RESUMO

BACKGROUND: Magnesium sulphate (MgSO(4)) has potent anti-inflammatory capacity. It is a natural calcium antagonist and a potent L-type calcium channel inhibitor. We sought to elucidate the possible role of calcium, the L-type calcium channels, or both in mediating the anti-inflammatory effects of MgSO(4). METHODS: RAW264.7 cells, an immortalized murine macrophage-like cell line, were treated with phosphate buffered saline, MgSO(4), lipopolysaccharide (LPS), LPS plus MgSO(4), LPS plus MgSO(4) plus extra-cellular supplement with calcium chloride (CaCl(2)), or LPS plus MgSO(4) plus the L-type calcium channel activator BAY-K8644. After harvesting, the production of inflammatory molecules was evaluated. Because the production of endotoxin-induced inflammatory molecules is regulated by the crucial transcription factor nuclear factor (NF)-kappaB, we also evaluated the expression of NF-kappaB. RESULTS: LPS significantly induced the production of inflammatory molecules, including macrophage inflammatory protein-2, tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, nitric oxide/inducible nitric oxide synthase, and prostaglandin E(2)/cyclo-oxygenase-2. LPS also induced NF-kappaB activation, as inhibitor-kappaB degradation, NF-kappaB nuclear translocation, and NF-kappaB-DNA binding activity were significantly increased in LPS-treated RAW264.7 cells. MgSO(4), in contrast, significantly inhibited the LPS-induced inflammatory molecules production and NF-kappaB activation. Moreover, the effects of MgSO(4) on inflammatory molecules and NF-kappaB were reversed by extra-cellular calcium supplement with CaCl(2) and L-type calcium channel activator BAY-K8644. CONCLUSIONS: MgSO(4) significantly inhibited endotoxin-induced up-regulation of inflammatory molecules and NF-kappaB activation in activated RAW264.7 cells. The effects of MgSO(4) on inflammatory molecules and NF-kappaB may involve antagonizing calcium, inhibiting the L-type calcium channels, or both.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/efeitos dos fármacos , Sulfato de Magnésio/farmacologia , Animais , Linhagem Celular Transformada , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , RNA Mensageiro/genética , Regulação para Cima/efeitos dos fármacos
5.
Acta Anaesthesiol Scand ; 50(6): 722-30, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16987368

RESUMO

BACKGROUND: We sought to investigate the potential therapeutic effects of acupuncture stimulation of ST-36 (Zusanli) on endotoxemia-induced acute lung injury in lipopolysaccharide (LPS)-stimulated rats. METHODS: Sixty rats were randomized into six groups (n = 10): (i) lipopolysaccharide (LPS) control group, (ii) normal saline (N/S) control group, (iii) LPS plus ST-36 group, (iv) N/S plus ST-36 group, (v) LPS plus sham point (Sham) group, and (vi) N/S plus Sham group. Manual acupuncture stimulation of ST-36 (designated as 'ST-36') or a 'non-acupoint' (designated as 'Sham') was performed in lightly immobilized rats for 30 min. Then, LPS injection was employed to induce sepsis. Rats were killed at 6 h after LPS injection and lung injury, nitric oxide (NO) biosynthesis and inducible NO synthase (iNOS) expression were assayed. RESULTS: Significant lung injury, pulmonary iNOS expression and systemic and pulmonary NO biosynthesis were noted in the LPS groups. Rats in the LPS plus Sham group had lung injury, pulmonary iNOS expression, systemic and pulmonary NO biosynthesis similar to those observed in the LPS group. However, the degree of lung injury, pulmonary iNOS expression and pulmonary NO biosynthesis, but not systemic NO biosynthesis, were significantly attenuated in the LPS plus ST-36 group as compared with those in both the LPS group and the LPS plus Sham group. CONCLUSION: Acupuncture stimulation of ST-36 may be effective as a prophylaxis measure against sepsis. However, results from this study do not support the use of acupuncture for the treatment of sepsis.


Assuntos
Acupuntura , Lipopolissacarídeos , Pneumopatias/induzido quimicamente , Pneumopatias/prevenção & controle , Animais , Pressão Sanguínea/efeitos dos fármacos , Western Blotting , Frequência Cardíaca/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Pneumopatias/patologia , Masculino , Óxido Nítrico/sangue , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Tamanho do Órgão/fisiologia , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Protoplasma ; 228(1-3): 137-44, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16937067

RESUMO

A study of male sterility over a period of three consecutive years on a conifer species endemic to Taiwan, Taiwania cryptomerioides Hayata (Taxodiaceae), was done for this article. With the aids of fluorescence and electron microscopic observations, the ontogenic processes in the fertile and sterile microsporangia are compared, using samples collected from Chitou Experimental Forest and Yeou-Shoei-Keng Clonal Orchard of the National Taiwan University, Nantou, Taiwan. The development of male strobili occurred from August to the end of March. Microsporogenesis starts with the formation of the archesporium and ends with the maturation of 2-celled pollen grains within the dehiscing microsporangium. Before meiosis, there was no significant difference in ultrastructure between the fertile and sterile microsporangia. Asynchronous pollen development with various tetrad forms may occur in the same microsporangium of either fertile or sterile strobili. However, a callose wall was observable in the fertile dyad and tetrad, but not in the sterile one. After dissolution of the callose wall, the fertile microspores were released into the locule, while some sterile microspores still retained as tetrads or dyads with intertwining of exine walls in the proximal faces. As a result, there was no well developed lamellated endexine and no granulate ectexine or intine in the sterile microspores. Eventually, the intracellular structures in sterile microspores were dramatically collapsed before anthesis. The present study shows that the abortion in pollen development is possibly attributed to the absence of the callose wall. The importance of this structure to the male sterility of T. cryptomerioides is discussed.


Assuntos
Cupressaceae/fisiologia , Infertilidade das Plantas/fisiologia , Glucanos/metabolismo , Pólen/ultraestrutura , Sementes/ultraestrutura
7.
Acta Anaesthesiol Scand ; 49(9): 1293-301, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16146466

RESUMO

BACKGROUND: Hyperbaric oxygen (HBO) attenuates lipopolysaccharide (LPS)-induced acute lung injury. This beneficial effect of HBO involves inhibition of inducible nitric oxide synthase (iNOS) expression and subsequent nitric oxide (NO) biosynthesis. We sought to investigate the role of heme oxygenase-1 (HO-1) on this HBO inhibition of iNOS induction and acute lung injury in septic rat lungs. METHODS: Before the experiment, 72 rats were randomly allocated to receive HBO or air treatment. With or without HBO pre-treatment, the rats were further divided into the following subgroups (n = 6): (i) LPS injection, (ii) normal saline (N/S) injection, (iii) hemin (a HO-1 inducer) plus LPS, (iv) hemin alone, (v) tin protoporphyrin (SnPP; a HO-1 inhibitor) plus LPS, and (vi) SnPP alone. All rats were maintained for 6 h and then sacrificed with a high-dose pentobarbital injection. Lung injuries and relevant enzymes expression were thus assayed. RESULTS: Histological analysis, PMNs/alveoli ratio, and wet/dry weight ratio measurements demonstrated that LPS caused significant lung injury and HBO and/or hemin significantly attenuated this LPS-induced lung injury. Increased pulmonary iNOS expression and NO production were associated with lung injury. Induction of HO-1, by HBO and/or hemin, significantly attenuated this LPS-induced iNOS expression and acute lung injury. SnPP, on the contrary, offset the effects of HBO and worsened the LPS-induced lung injury. CONCLUSIONS: HBO may act through inhibiting pulmonary iNOS expression to attenuate LPS-induced acute lung injury in septic rats. Furthermore, this HBO attenuation of iNOS expression involves HO-1 induction.


Assuntos
Heme Oxigenase-1/metabolismo , Oxigenoterapia Hiperbárica , Lipopolissacarídeos/toxicidade , Pneumopatias/induzido quimicamente , Pneumopatias/prevenção & controle , Animais , Indução Enzimática/fisiologia , Hemina/farmacologia , Pulmão/patologia , Pneumopatias/metabolismo , Masculino , Neutrófilos/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Tamanho do Órgão/fisiologia , Protoporfirinas/farmacologia , Alvéolos Pulmonares/patologia , RNA/biossíntese , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sepse/enzimologia , Sepse/fisiopatologia
8.
Br J Pharmacol ; 137(8): 1314-20, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12466241

RESUMO

1. Baicalein is a bioactive flavonoid isolated from the root of Scutellaria baicalensis Georgi, a medicinal herb that has been used since ancient times to treat bacterial infections. As little is known concerning its pharmacokinetics, this study focussed on its pharmacokinetics as well as the possible roles of the multidrug transporter P-glycoprotein on its distribution and disposition. 2. Three microdialysis probes were simultaneously inserted into the jugular vein, the hippocampus and the bile duct of male Sprague-Dawley rats for sampling in biological fluids following the administration of baicalein (10, 30 and 60 mg kg(-1)) through the femoral vein. The P-glycoprotein inhibitor cyclosporin A was used to help delineate its roles. 3. The study design consisted of two groups of six rats in parallel: control rats which received baicalein alone and the cyclosporin A treated-group in which the rats were injected cyclosporin A, a P-glycoprotein inhibitor, 10 min prior to baicalein administration. 4. Cyclosporin A treatment resulted in a significant increase in elimination half-life, mean residence time and area under the concentration versus time curve (AUC) of unbound baicalein in the brain. However, AUC in the bile was decreased. 5. The decline of baicalein in the hippocampus, blood and bile suggested that there was rapid exchange and equilibration between the peripheral compartment and the central nervous system. In addition, the results indicated that baicalein was able to penetrate the blood-brain barrier as well as undergoing hepatobiliary excretion. 6. Although no direct transport studies were undertaken and multiple factors may affect BBB penetration and hepatobiliary excretion, strong association of the involvement of P-glycoprotein in these processes is indicated.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Ciclosporina/farmacologia , Ciclosporina/farmacocinética , Flavanonas , Flavonoides/farmacocinética , Microdiálise/métodos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Área Sob a Curva , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Interações Medicamentosas , Flavonoides/sangue , Flavonoides/química , Masculino , Ratos , Ratos Sprague-Dawley
9.
Rapid Commun Mass Spectrom ; 15(16): 1473-80, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11507761

RESUMO

Sixteen synthetic chemical drugs, often found in adulterated Chinese medicines, were studied by capillary electrophoresis/UV absorbance (CE/UV) and capillary electrophoresis/electrospray ionization mass spectrometry (CE/ESI-MS). Only nine peaks were detected with CZE/UV, but on-line CZE/MS provided clear identification for most compounds. For a real sample of a Chinese medicinal preparation, a few adulterants were identified by their migration times and protonated molecular ions. For coeluting compounds, more reliable identification was achieved by MS/MS in selected reaction monitoring mode. Micellar electrokinetic chromatography (MEKC) using sodium dodecyl sulfate (SDS) provided better separation than capillary zone electrophoresis (CZE), and, under optimal conditions, fourteen peaks were detected using UV detection. In ESI, the interference of SDS was less severe in positive ion mode than in negative ion mode. Up to 20 mM SDS could be used in direct coupling of MEKC with ESI-MS if the mass spectrometer was operated in positive ion mode. Because of better resolution in MEKC, adulterants can be identified without the use of MS/MS.


Assuntos
Anti-Inflamatórios/análise , Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/química , Anti-Inflamatórios/química , Cafeína/análise , Cafeína/química , Diazepam/análise , Diazepam/química , Eletroforese Capilar/métodos , Micelas , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Ultravioleta , Taiwan
10.
Endocrinology ; 142(8): 3309-16, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11459772

RESUMO

The peripubertal transition in male mammals is accompanied by a gradual decrease in sensitivity to the inhibitory effects exerted by gonadal hormones, such as T and E2. Here, we investigated the effects of chronic T and its metabolites, 5alpha-dihydrotestosterone and E2 on the hypothalamo-pituitary-gonadal axis at puberty. We also examined if T effects are distinct or mediated through its conversion to 5alpha-dihydrotestosterone or E2. Twenty-day-old male Siberian hamsters were sc implanted with a SILASTIC brand capsule containing varying doses of T, 5alpha-dihydrotestosterone, or E2. Several functional parameters of the hypothalamo-pituitary-gonadal axis were evaluated including hypothalamic GnRH concentration, pituitary and plasma FSH levels, pituitary FSH and LH mRNA, and testicular status. Our results showed that gonadal steroids inhibited puberty in a dose-dependent manner as evaluated by testes mass (undiluted steroid: T, 27 +/- 3 mg; 5alpha-dihydrotestosterone, 18 +/- 1 mg; and E2, 62 +/- 4 mg relative to cholesterol-implanted controls, 510 +/- 42 mg). Also, T decreased plasma FSH below detectable levels, but pituitary FSH concentration was unaffected (1.37 +/- 0.16 ng/microg protein) while E2-treated hamsters had normal plasma FSH levels (3.5 +/- 0.98 ng/ml) yet significantly lower pituitary FSH concentration (0.09 +/- 0.04 ng/microg protein). These results showed that the pathways of T and E2 action on the hypothalamo-pituitary-gonadal axis are distinct.


Assuntos
Estradiol/farmacologia , Testosterona/farmacologia , Animais , Cricetinae , Di-Hidrotestosterona/farmacologia , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/genética , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Hormônio Luteinizante/genética , Masculino , Tamanho do Órgão/efeitos dos fármacos , Phodopus , Hipófise/metabolismo , RNA Mensageiro/metabolismo , Testículo/anatomia & histologia , Testosterona/sangue , Fatores de Tempo
12.
Am J Physiol ; 271(6 Pt 2): R1739-45, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8997377

RESUMO

Pregnancy is characterized by hemodynamic and body fluid alterations. Increased nitric oxide (NO) production has been suggested to play a role in the hemodynamic alterations of pregnancy and has also been reported to increase arginine vasopressin (AVP) release. We therefore hypothesized that gestation could increase both NO synthase (NOS) constitutive isoforms, neuronal NOS and endothelial NOS, and thereby contribute to the hyposmolality and peripheral arterial vasodilation of pregnancy, respectively. The present study was therefore undertaken to examine the constitutive NOS isoforms in aortas, mesenteric arteries, and hypothalami of pregnant rats on day 20 of gestation compared with age-matched nonpregnant rats. Plasma AVP was determined by radioimmunoassay and hypothalamic mRNA AVP by solution hybridization assay. Hypothalamic neuronal NOS was assessed by Northern blot and Western blot; endothelial NOS was assessed by Western blot in arteries and hypothalamus. The results demonstrated that 1) plasma AVP and hypothalamic AVP mRNA are increased in pregnant rats (n = 8), 2) neuronal NOS protein and mRNA are increased in hypothalamus of pregnant rats (n = 4), and 3) endothelial NOS expression, as assessed by Western blot analysis, is increased in both conductance (aorta) as well as resistance (mesenteric) arteries of pregnant rats (n = 4). We conclude that both of the constitutive NOS isoforms are increased in pregnant rats, suggesting that the peripheral arterial vasodilation and hyposmolality of pregnancy could be mediated by these isoforms.


Assuntos
Endotélio Vascular/enzimologia , Neurônios/enzimologia , Óxido Nítrico Sintase/metabolismo , Prenhez/metabolismo , Animais , Arginina Vasopressina/sangue , Arginina Vasopressina/genética , Feminino , Hipotálamo/metabolismo , Isoenzimas/metabolismo , Concentração Osmolar , Gravidez , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Sódio/sangue
13.
J Chromatogr B Biomed Appl ; 657(2): 285-90, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-7952092

RESUMO

The procedures for the preparation of silica capillaries coated with titanium oxide or aluminum oxide are developed. These inorganic coated capillaries are studied for their applicability in capillary electrophoresis. The points of zero charge are measured as pH 5 and pH 7 for titanium oxide- and aluminum oxide-coated capillaries, respectively. Both titanium oxide and aluminum oxide coatings give better protein separations in comparison to the use of fused-silica capillaries. Separation efficiency of lysozyme as model protein is measured in the range of 20,000 theoretical plates/m of inorganic coated capillaries. However, the hydrophobic interaction between proteins and modified capillary wall possibly contributes to the tailing of observed protein peaks.


Assuntos
Eletroforese/instrumentação , Adsorção , Óxido de Alumínio/química , Eletroquímica , Eletroforese/métodos , Proteínas/química , Dióxido de Silício , Titânio/química
14.
Kidney Int ; 44(4): 755-63, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8258953

RESUMO

The present study was undertaken to examine the effects of diminished extracellular sodium concentration on the vascular action of arginine vasopressin (AVP) in cultured rat vascular smooth muscle cells (VSMC). The preincubation of cells with the 110 mM extracellular Na+ ([Na+]e) solution supplemented with 30 mM choline chloride for 60 minutes enhanced the effect of AVP- (1 x 10(-8) M) induced VSMC contraction. The treatment of 110 mM [Na+]e solution also enhanced the cellular contractile response to the protein kinase C (PKC) activators, phorbol 12-myristate 13-acetate and 1-oleoyl-2-acetyl-glycerol. Furthermore, preincubation with the 110 mM [Na+]e solution also potentiated the effect of 1 x 10(-8) M AVP, but not 1 x 10(-6) M, to increase the cytosolic-free Ca2+ ([Ca2+]i) concentration. The 110 mM [Na+]e media decreased the basal intracellular Na+ concentration and increased intracellular 45Ca2+ accumulation, basal [Ca2+]i and AVP-produced 45Ca2+ efflux. These effects of 110 mM [Na+]e solution to enhance the vascular action of AVP were abolished by using Ca(2+)-free 110 mM [Na+]e solution during the preincubation period. The preincubation with the 110 mM [Na+]e solution did not change either the Kd and Bmax of AVP V1 receptor of VSMC or the AVP-induced production of inositol 1,4,5-trisphosphate. The present in vitro results therefore indicate that the diminished extracellular fluid sodium concentration within a range observed in clinical hyponatremic states enhances the vascular action of AVP.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arginina Vasopressina/farmacologia , Vasos Sanguíneos/efeitos dos fármacos , Espaço Extracelular/metabolismo , Sódio/metabolismo , Animais , Arginina Vasopressina/metabolismo , Vasos Sanguíneos/citologia , Vasos Sanguíneos/metabolismo , Cálcio/farmacocinética , Células Cultivadas , Diglicerídeos/farmacologia , Fosfatos de Inositol/biossíntese , Membranas Intracelulares/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Concentração Osmolar , Ratos , Receptores de Vasopressinas/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Vasoconstrição/fisiologia
15.
Am J Hypertens ; 6(4): 268-75, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8507445

RESUMO

In cultured rat vascular smooth muscle cells (VSMC), acute preincubation of 100 mmol/L ethanol for 30 min attenuated the number of contracting cells in response to (10(-7) mol/L) arginine vasopressin (AVP) (P < .01). In contrast, VSMC cultured chronically for 3 days in medium supplemented with 100 mmol/L ethanol enhanced (10(-7) mol/L) AVP-induced shape change (P < .01). Specific 3H-AVP binding to VSMC after acute or chronic exposure to 100 mmol/L ethanol did not differ from those of control experiments. Acute ethanol pretreatment attenuated basal, 10(-7) mol/L AVP-, 65 mmol/L K(+)-stimulated Ca2+ uptake, in a dose-dependent manner. In contrast, 100 mmol/L ethanol for 4 days enhanced the (P < .001) AVP- 10(-7) mol/L and (P < .01) 65 mmol/L K(+)-stimulated 45Ca2+ uptake. Acute ethanol exposure inhibited and chronic ethanol administration enhanced Ca2+ uptake stimulated by 6 x 10(-7) mol/L Bay K 8644, an activator of voltage-sensitive Ca2+ channels. Nifedipine, a blocker of these Ca2+ channels, diminished AVP-stimulated (P < .02) and K(+)-induced (P < .001) Ca2+ uptake more potently in VSMC pretreated for 4 days with 100 mmol/L ethanol than in control cells. Acute ethanol preexposure for 30 min attenuated AVP-stimulated inositol trisphosphate (IP3) formation (P < .05) and the rise in cytosolic free Ca2+ ([Ca2+]i) (P < .01). In contrast, chronic ethanol-treated VSMC enhanced IP3 formation (P < .05) and the rise in [Ca2+]i (P < .01) in response to AVP.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cálcio/farmacocinética , Etanol/administração & dosagem , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Animais , Arginina Vasopressina/metabolismo , Células Cultivadas , Eletrofisiologia , Etanol/farmacologia , Fosfatos de Inositol/metabolismo , Membranas Intracelulares/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Concentração Osmolar , Potássio/farmacologia , Receptores de Vasopressinas/fisiologia , Fatores de Tempo
16.
J Biol Chem ; 253(14): 5087-9, 1978 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-670179

RESUMO

Hydrocortisone stimulated the catabolism of prelabeled fatty acyls in mouse L fibroblasts supplemented with exogenous fatty acid. Both oxidation to 14CO2 and release as free fatty acid from prelabeled lipids increased up to 20-fold under the described experimental conditions. The stimulating effect of hydrocortisone was observed even at concentrations as low as 1 microgram/ml. Neither the hormone nor exogenous fatty acid alone had a significant effect on endogenous fatty acyl catabolism. The activity of a cellular pH 6.5 lipase was unaffected by exogenous fatty acid, slightly increased by hydrocortisone, but increased 2-fold when both supplements were present. It is suggested that since exogenous fatty acids shunt phospholipid acyls to triglycerides, the latter induce the formation of more pH 6.5 lipase. Hydrocortisone is either needed for this induction to occur, or activates the newly formed enzyme. The lipase acts on the triglycerides to liberate free fatty acids that are then oxidized to 14CO2 or lost into the medium.


Assuntos
Ácidos Graxos/metabolismo , Hidrocortisona/farmacologia , Células L/metabolismo , Acetatos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células L/efeitos dos fármacos , Mobilização Lipídica/efeitos dos fármacos , Fosfolipídeos/metabolismo , Esteróis/metabolismo , Triglicerídeos/metabolismo
17.
Biochim Biophys Acta ; 489(3): 381-9, 1977 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-588578

RESUMO

Strain L mouse fibroblasts grown in medium supplemented with 2.5% delipidized horse serum were found capable of desaturating oleic and linoleic acid to dienoic and trienoic acid(s), respectively. Although 40-60% of de novo fatty acid synthesis from [2-3H]acetate was inhibited by the administration of exogenous oleic or linoleic acid, sterole synthesis was only slightly affected. Within 24-48 h after incorporation, phospholipid fatty acyl groups could undergo active exchange between phospholipids. After this dynamic transition period was over, not only were the phospholipid acyls retained but some vicinal fatty acyl pairs of phospholipid also appeared to be stable and remained together throughout the depletion period. At any time in the experiment, however, introduction of exogenous fatty acid perturbed this phospholipid acyl retention, delayed the time at which the phospholipid acyl groups no longer moved between phospholipids and also decreased the ultimate number of phospholipid acyl groups retained by strain L mouse fibroblasts.


Assuntos
Ácidos Graxos/biossíntese , Células L/metabolismo , Fosfolipídeos/metabolismo , Cinética , Células L/efeitos dos fármacos , Ácidos Linoleicos/metabolismo , Ácidos Linoleicos/farmacologia , Lipídeos/biossíntese , Ácidos Oleicos/metabolismo , Ácidos Oleicos/farmacologia , Esteróis/biossíntese
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