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1.
Eur Rev Med Pharmacol Sci ; 22(6): 1595-1601, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29630101

RESUMEN

OBJECTIVE: This study intended to explore the efficacy of computed tomography (CT)-guided implantation of iodine-125 (125I) seeds in the treatment of refractory malignant tumors with cancer pain and its influence on tumor markers in the serum. PATIENTS AND METHODS: 76 patients with refractory malignant tumors accompanied by cancer pain that received treatments in LongHua Hospital Shanghai University of Traditional Chinese Medicine from September 2013 to August 2014 were selected. They were divided into control group and observation group using a random number table (38 patients in each group). Patients in the control group received simple chemotherapy, while those in the observation group undergone CT-guided implantation of 125I seeds in combination with chemotherapy. Recent efficacy and 1-3-year survival rate were compared between the two groups of patients. The degree of pain relief after treatment was also compared between the two groups of patients. Electrochemiluminescence method was used to detect the concentrations of carcinoembryonic antigen (CEA), sugar chain antigen 199 (CA 199), sugar chain antigen 125 (CA 125), neuron-specific enolase (NSE) and cytokeratin-19-fragment (CYFRA21-1) in the two groups of patients before treatment, and 3 days, 7 days and 30 days after treatment. RESULTS: Recent disease control rate of the patients in the observation group was higher than that of the patients in the control group (p<0.05). The 1-3-year survival rate after surgery in the observation group was significantly higher than that in the control group (p<0.05). The total efficiency of pain control in the observation group was significantly higher than that in the control group (p<0.05). The levels of tumor markers in the two groups of patients were significantly decreased after treatment, while the reduction in the observation group was more evident than that in the control group (p<0.05). CONCLUSIONS: Our results showed that CT-guided implantation of 125I seeds is effective for the treatment of patients with refractory malignant tumors accompanied by cancer pain. It can reduce the levels of tumor markers, improve the survival rate and prolong the survival time of the patients.


Asunto(s)
Dolor en Cáncer/patología , Neoplasias/radioterapia , Radiofármacos/uso terapéutico , Adulto , Anciano , Antígenos de Neoplasias/análisis , Antineoplásicos/uso terapéutico , Antígeno Carcinoembrionario/análisis , Femenino , Humanos , Radioisótopos de Yodo/química , Queratina-19/análisis , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/mortalidad , Fosfopiruvato Hidratasa/análisis , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
2.
Int J Antimicrob Agents ; 42(3): 276-80, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23830892

RESUMEN

Invasive fungal infections (IFIs) are a major concern within healthcare systems. This pharmacoeconomic study evaluated the use of caspofungin (CAS) versus liposomal amphotericin B (L-AmB) in the empirical treatment of IFIs within the Turkish healthcare system. A decision-analytic model was adopted, utilising data from a randomised, non-inferiority clinical trial and a panel of clinical experts in Turkey. A five-point composite outcome measure was used to evaluate both agents. Sensitivity analyses were performed. In the base-case scenario, CAS was preferred over L-AmB by Turkish Lira (TL) 3961 per patient treated, TL 12 904 per successfully treated patient and TL 3972 per death averted. One-way sensitivity analysis did not change the study outcome. Monte Carlo simulation concluded a 71.0% chance of the outcome favouring CAS. The results were most sensitive to changes in length of stay. This is the first economic evaluation of the empirical treatment of IFIs in Turkey and suggests that CAS is more cost effective than L-AmB.


Asunto(s)
Anfotericina B/economía , Anfotericina B/uso terapéutico , Equinocandinas/economía , Equinocandinas/uso terapéutico , Micosis/tratamiento farmacológico , Antifúngicos/economía , Antifúngicos/uso terapéutico , Caspofungina , Análisis Costo-Beneficio , Atención a la Salud/estadística & datos numéricos , Neutropenia Febril/tratamiento farmacológico , Neutropenia Febril/microbiología , Fiebre/tratamiento farmacológico , Fiebre/economía , Humanos , Lipopéptidos , Pruebas de Sensibilidad Microbiana , Micosis/economía , Turquía
3.
Neurogastroenterol Motil ; 25(6): e429-40, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23638900

RESUMEN

BACKGROUND: An antinociceptive effect has been reported for curcumin in animal models and in humans, but the molecular mechanisms of curcumin's effect remain undefined. In this study, we explored the possibility that curcumin inhibit visceral nociception via antagonizing the transient receptor potential vanilloid-1 (TRPV1) receptor. METHODS: The effects of curcumin were explored using two experimental models: viscero-motor response (VMR) to colorectal distension (CRD) in rats and jejunal afferent firing in the ex vivo mouse jejunum preparations [TRPV1 knockout (KO) and wild-type mice, naive and trinitrobenzene sulfonic acid (TNBS)-treated Kunming mice]. In addition, capsaicin-induced calcium transients and whole-cell currents were examined in acutely dissociated dorsal root ganglia (DRG) neurons. KEY RESULTS: In the anesthetized rat, curcumin (4 mg kg(-1)  min(-1) for 3 min) caused a marked and rapidly reversible inhibition of CRD-induced VMRs. In the mouse jejunum, the mesenteric afferent nerve response to ramp distension was attenuated by curcumin (3, 10 µmol L(-1) ), an effect that was significantly reduced in TRPV1 KO mice compared with wild-type (WT) controls. Moreover, in WT mice, curcumin (1-30 µmol L(-1) ) was found to inhibit the afferent responses to capsaicin in a concentration-dependent manner. Trinitrobenzene sulfonic acid-induced hypersensitivity of jejunal afferents was also attenuated by curcumin. Curcumin potently inhibited capsaicin-induced rise in intracellular calcium and inward currents in mouse or rat DRG neurons. CONCLUSIONS & INFERENCES: Our results provide strong evidence that curcumin inhibit visceral nociception via antagonizing TRPV1 and may be a promising lead for the treatment of functional gastrointestinal diseases.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Curcumina/uso terapéutico , Hiperalgesia/tratamiento farmacológico , Nocicepción/efectos de los fármacos , Canales Catiónicos TRPV/metabolismo , Vísceras/efectos de los fármacos , Animales , Antiinflamatorios no Esteroideos/farmacología , Curcumina/farmacología , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatología , Masculino , Ratones , Ratones Noqueados , Neuronas Aferentes/efectos de los fármacos , Neuronas Aferentes/fisiología , Ratas , Ratas Sprague-Dawley , Canales Catiónicos TRPV/genética , Vísceras/metabolismo
4.
Zhongguo Zhong Yao Za Zhi ; 26(10): 689-90, 2001 Oct.
Artículo en Chino | MEDLINE | ID: mdl-12776316

RESUMEN

OBJECTIVE: To study the chemical constituents from the upground part of Erigeron breviscapus. METHOD: The compounds were separated and purified by column chromatography with silica gel, and identified by IR, MS, NMR and 2D-NMR. RESULT: Two new compounds were isolated and identified as 5,4'-dihydroxy flavonod-7-O-beta-D-pyranglycuronate buthyl ester(VI) and 3,5-dimethoxy benzene carbonic acid-4-O-beta-D-pyranglucose(VII). CONCLUSION: Compounds VI and VII were new compounds.


Asunto(s)
Asteraceae/química , Benzoatos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Glucósidos/aislamiento & purificación , Glucuronatos/aislamiento & purificación , Glicósidos/aislamiento & purificación , Plantas Medicinales/química , Benzoatos/química , Flavonoides/química , Glucósidos/química , Glucuronatos/química , Glicósidos/química , Estructura Molecular , Éteres Fenílicos
5.
Yao Xue Xue Bao ; 36(5): 360-3, 2001 May.
Artículo en Chino | MEDLINE | ID: mdl-12584859

RESUMEN

AIM: To isolate and identify the active constituents of Erigeron brevisapus (Vant.) Hand.-Mazz. METHODS: The chemical constituents were isolated by silica gel column chromatography and two new compounds were obtained. Their structures were elucidated by IR, MS, 1HNMR, 13CNMR, DEPT and 2DNMR. The injury of BCMEC (bovine cerebral microvascular endothelial cell) was determined by lactic dehydrogenase (LDH), the ability of the drugs anti-oxidation and scavenging oxidation of free radical was measured by colorimetric method. RESULTS: Two new compounds have been identified as 1-O-methyl-3, 5-O-dicaffeoyl quinic acid methyl ester (III) and 5-O-caffeoyl quinic acid butyl ester (IV). CONCLUSION: Compounds III and IV are new compounds. Compound III can protect BCMEC injury by LPC.


Asunto(s)
Asteraceae/química , Ácidos Cafeicos/aislamiento & purificación , Endotelio Vascular/efectos de los fármacos , Plantas Medicinales/química , Ácido Quínico/aislamiento & purificación , Animales , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacología , Bovinos , Separación Celular , Endotelio Vascular/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Microcirculación/citología , Estructura Molecular , Sustancias Protectoras/aislamiento & purificación , Sustancias Protectoras/farmacología , Ácido Quínico/análogos & derivados , Ácido Quínico/química , Ácido Quínico/farmacología
6.
Zhongguo Zhong Yao Za Zhi ; 25(9): 536-8, 2000 Sep.
Artículo en Chino | MEDLINE | ID: mdl-12516462

RESUMEN

OBJECTIVE: To study the chemical constituents of Erigeron breviscapus. METHOD: The constituents were separated and purified by column chromatography with silica gel, and identified by IR, MS, NMR and physical data. RESULT: Five compounds were isolated and identified as 3, 5, 6, 4'-tetrahydroxy-7-methoxy flavonoid(I); 5, 7, 4'-trihydroxy flavonoid(II); 3, 5, 6, 7, 4'-pentahydroxy flavonoid(III); scutellarein (IV) and 5, 7, 4'-trihydroxy flavanone(V). CONCLUSION: Compounds I, III and V were isolated from this plant for the first time.


Asunto(s)
Apigenina , Asteraceae/química , Flavonoides/aislamiento & purificación , Glucuronatos , Plantas Medicinales/química , Flavonoides/química
7.
J Asian Nat Prod Res ; 2(4): 283-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11249610

RESUMEN

Two new constituents with a novel basic skeleton were isolated from Erigeron breviscapus. On the basis of chemical and spectroscopic evidences, the structures of the new compounds were elucidated as 1R,3R-dihydroxy-4S,5R-dicaffeoyloxy cyclohexane carboxylic acid methyl ester (V), 1,4-dihydroxy-3R,5R-dicaffeoyloxy cyclohexane carboxylic acid methyl ester (VI).


Asunto(s)
Ácidos Cafeicos/química , Ciclohexanos/química , Plantas Medicinales/química , Ácidos Cafeicos/aislamiento & purificación , China , Ciclohexanos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Conformación Molecular , Extractos Vegetales/análisis , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría Infrarroja
8.
Oncogene ; 18(28): 4063-8, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10435587

RESUMEN

The insulin-like growth factor II receptor (IGFIIR) has been implicated as a tumor suppressor gene in human malignancy. Frequent mutation, loss of heterozygosity, and microsatellite instability (MSI) directly affecting the IGFIIR gene have been reported in several primary human tumor types. However, to our knowledge, dynamic functional evidence of a growth-suppressive role for IGFIIR has not yet been provided. We identified one MSI-positive colorectal carcinoma cell line, SW48, with monoallelic mutation in IGFIIR identical to that seen in primary colorectal carcinomas. A zinc-inducible construct containing the wild-type IGFIIR cDNA was stably transfected into SW48 cells. Growth rate and apoptosis were compared between zinc-treated, untreated, and untransfected cells. A twofold increase in IGFIIR protein expression was detected after zinc treatment in discrete clonal isolates of transfected SW48 cells. Moreover, zinc induction of exogenous wild-type IGFIIR expression reproducibly decreased growth rate and increased apoptosis. These data prove that wild-type IGFIIR functions as a growth suppressor gene in colorectal cancer cells and provide dynamic in vitro functional support for the hypothesis that IGFIIR is a human growth suppressor gene.


Asunto(s)
Adenocarcinoma/patología , Apoptosis/genética , Neoplasias Colorrectales/patología , Receptor IGF Tipo 2/fisiología , Adenocarcinoma/genética , División Celular/genética , Neoplasias Colorrectales/genética , ADN Complementario/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Factor II del Crecimiento Similar a la Insulina/fisiología , Pérdida de Heterocigocidad , Metalotioneína/genética , Repeticiones de Microsatélite , Proteínas de Neoplasias/deficiencia , Proteínas de Neoplasias/genética , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas/efectos de los fármacos , Receptor IGF Tipo 2/deficiencia , Receptor IGF Tipo 2/genética , Células Tumorales Cultivadas , Zinc/farmacología
9.
Am J Physiol ; 276(5): H1468-81, 1999 05.
Artículo en Inglés | MEDLINE | ID: mdl-10330229

RESUMEN

Using conscious rabbits, we examined the effect of ischemic preconditioning (PC) on p44 and p42 mitogen-activated protein kinases (MAPKs). We found that both isoforms contribute significantly to total MAPK activity in the heart (in-gel kinase assay: p44, 59 +/- 1%; p42, 41 +/- 1%). Ischemic PC (6 cycles of 4-min occlusion/4-min reperfusion) elicited a pronounced increase in total cellular MAPK activity (+89%). This increase, which occurred exclusively in the nuclear fraction, was contributed by both isoforms (in-gel kinase assay: p44, +97%; p42, +210%) and was accompanied by migration of the two proteins from the cytosolic to the nuclear compartment. In control rabbits, MAPK kinase (MEK)1 and MEK2, direct activators of p44 and p42 MAPKs, were located almost exclusively in the cytosolic fraction. Ischemic PC induced a marked increase in cytosolic MEK activity (+164%), whereas nuclear MEK activity did not change, indicating that MEK-induced activation of MAPKs occurred in the cytosolic compartment. Activation of MAPKs after ischemic PC was completely blocked by the protein kinase C (PKC) inhibitor chelerythrine. Selective overexpression of PKC-epsilon in adult rabbit cardiomyocytes induced activation of both p44 and p42 MAPKs and reduced lactate dehydrogenase release during simulated ischemia-reperfusion, which was abolished by the MEK inhibitor PD-98059. The results demonstrate that 1) ischemic PC induces a rapid activation of p44 and p42 MAPKs in hearts of conscious rabbits; 2) the mechanism of this phenomenon involves activation of p44 and p42 MAPKs in the cytosol and their subsequent translocation to the nucleus; and 3) it occurs via a PKC-mediated signaling pathway. The in vitro data implicate PKC-epsilon as the specific isoform responsible for PKC-induced MAPK activation and suggest that p44/p42 MAPKs contribute to PKC-epsilon-mediated protection against simulated ischemia. The results are compatible with the hypothesis that p44 and p42 MAPKs may play a role in myocardial adaptations to ischemic stress.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Isoenzimas/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos , Proteínas Quinasas Activadas por Mitógenos , Isquemia Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Proteína Quinasa C/metabolismo , Alcaloides , Secuencia de Aminoácidos , Animales , Benzofenantridinas , Compartimento Celular/fisiología , Núcleo Celular/enzimología , Células Cultivadas , Estado de Conciencia , Vasos Coronarios/fisiología , Citosol/enzimología , ADN Complementario , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Precondicionamiento Isquémico , Isoenzimas/genética , MAP Quinasa Quinasa 1 , MAP Quinasa Quinasa 2 , Masculino , Proteína Quinasa 3 Activada por Mitógenos , Datos de Secuencia Molecular , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/enzimología , Fenantridinas/farmacología , Proteína Quinasa C/genética , Proteína Quinasa C-epsilon , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Conejos , Transducción de Señal/fisiología
10.
J Hypertens ; 14(10): 1237-45, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8906524

RESUMEN

OBJECTIVE: To assess the effectiveness of nifedipine treatment in elderly hypertensives. METHODS: A single-blind trial was conducted under the direction of the Shanghai Institute of Hypertension in 1632 subjects aged 60-79 years alternatively allocated to either nifedipine or placebo after a 4-week placebo run-in period between 1987 and 1990 with mean follow-up of 30 months. Clinical events and risk modification were analysed in collaboration with the University of Montreal. Seventy-four patients with severe hypertension were reallocated to active nifedipine treatment after placebo run-in. RESULTS: Cox's proportional hazards model accounting for covariates demonstrated a highly significant decrease in the probability of events: 'original treatment assignment' analysis indicated that 77 events occurred in the placebo and 32 in the nifedipine group. Similar significances were achieved with 'actual treatment' or 'changes excluded' (excluding reallocated subjects) analyses. A significant reduction in relative risk was observed for strokes and severe arrhythmia with an overall decrease from 1.0 to 0.41 (95% confidence interval 0.27-0.61). CONCLUSION: Nifedipine treatment diminished the number of severe clinical outcomes in elderly hypertensives significantly.


Asunto(s)
Bloqueadores de los Canales de Calcio/uso terapéutico , Hipertensión/tratamiento farmacológico , Nifedipino/uso terapéutico , Anciano , Arritmias Cardíacas/epidemiología , Trastornos Cerebrovasculares/epidemiología , Estudios de Cohortes , Humanos , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Método Simple Ciego
11.
Yao Xue Xue Bao ; 27(10): 792-5, 1992.
Artículo en Chino | MEDLINE | ID: mdl-1293930

RESUMEN

From the ethanol extract of Viscum coloratum (Kom.) Nakai, a glucoside of aliphatic diol and three other glucosides were isolated. Based on chemical and spectroscopic analysis, the structures have been elucidated as 2-beta-D-glucosyl-3-methylpropanol (VIII), syringin (IX), eleatheroside E (X) and syringenin-4'-O-D-apiosylglucoside (XI). VIII is a new glucoside of aliphatic diol and named 3-beta-D-glucopyranosyloxy-butanol-2. Three other compounds (IX-XI) were found for the first time in this plant.


Asunto(s)
Muérdago/química , Plantas Medicinales , Butanoles/química , Butanoles/aislamiento & purificación , Glucósidos/química , Glucósidos/aislamiento & purificación , Estructura Molecular
12.
Yao Xue Xue Bao ; 25(5): 349-52, 1990.
Artículo en Chino | MEDLINE | ID: mdl-2284954

RESUMEN

In order to determine the absolute configuration of the chiral center of viscumneoside IV, which was isolated from Viscum coloratum (Kom) Nakai, (R, S)-mevalonolactone was synthesized as shown in scheme 1. Then treatment with (S) (-)-1-phenylethylamine in THF gave two diasteromeric amides, which were transformed into the monoacetates and separated by HPLC. The first eluted peak (tR10.07 min.) had the (R)-configuration and the second one the (S)-configuration (tR11.20 min). Viscumneoside IV was treated with borane and hydrolyzed to give mevalonolactone which was treated with (S)-(-)-1-phenylethylamine in THF as mentioned above. The monoacetates of the resulting amides were subjected to HPLC. By comparison with the reference peaks, the absolute configuration at the acyl moiety of viscumneoside IV was shown to have the (R)-configuration.


Asunto(s)
Flavonoides/química , Glicósidos/química , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos , Ácido Mevalónico/análogos & derivados , Conformación Molecular
13.
Yao Xue Xue Bao ; 25(8): 608-11, 1990.
Artículo en Chino | MEDLINE | ID: mdl-2082684

RESUMEN

From the ethanol extract of Viscum coloratum (Kom.) Nakai, a new flavonoid has been isolated. Based on chemical and spectroscopic analysis, the structure of VII has been elucidated as rhamnazin-3-0-beta-D-apisoyl-(1----2)-[6"-O-(3-hydroxy-3- methylglutarate)]- glucoside and named Viscumneoside VII.


Asunto(s)
Medicamentos Herbarios Chinos/química , Flavonoides/aislamiento & purificación , Glicósidos/aislamiento & purificación , Flavonoides/química , Glicósidos/química
14.
Ann Acad Med Singap ; 18(3): 261-5, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2672993

RESUMEN

The concept of stress management was reviewed in this paper. Stress was conceptualised as a perception of inability to cope with its attendant emotional and psychophysiological responses. Management of stress then has to do with altering environmental triggers where possible. Alteration to more realistic mode of perception, adoption of more adaptive means of emotional response as well as the modulation of the body's psychophysiological state through the use of various relaxation techniques would all help to reduce stress and enable the individual to cope with it. The role of biofeedback in promoting the relaxation response as well as training the individual to adapt to better means of coping was discussed. Thirty-three anxious patients who were treated with biofeedback assisted relaxation training were studied for their response on EMG reading and heart rate. Their psychosocial functioning on an experiential index also showed an improvement. It was concluded that whatever techniques are used, a multi-modal approach to stress management is probably the more effective in helping people to cope with the variety of stress faced in life.


Asunto(s)
Biorretroalimentación Psicológica , Estrés Psicológico/prevención & control , Adulto , Ansiedad/fisiopatología , Ansiedad/prevención & control , Electromiografía , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Terapia por Relajación , Factores Sexuales , Estrés Psicológico/fisiopatología
15.
J Neurosurg ; 69(3): 416-20, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3404240

RESUMEN

To clarify the contribution of vasoconstrictor prostaglandins to the hypoperfusion state typically following total global cerebral ischemia, 14 mongrel dogs were subjected to 11 minutes of global cerebral ischemia. They were then randomly assigned to receive either no treatment or an intravenous bolus of the calcium channel blocker nimodipine, 10 micrograms/kg, 15 minutes after ischemia followed by a continuous infusion of nimodipine, 1.0 micrograms/kg/min. Thromboxane (Tx) A2 production, as measured by cerebral venous levels of TxB2 (the stable metabolite of TxA2) increased similarly in the two groups. In contrast to previous studies, mean postischemic cerebral blood flow did not increase sufficiently in the nimodipine-treated group to achieve statistical significance. These data suggest that the improved neurological outcome associated with nimodipine treatment following global cerebral ischemia does not relate to reduced levels of the prostaglandin precursor arachidonate.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Nimodipina/uso terapéutico , Tromboxano A2/sangre , Animales , Isquemia Encefálica/sangre , Circulación Cerebrovascular/efectos de los fármacos , Perros
18.
J Appl Physiol (1985) ; 61(1): 185-91, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3525503

RESUMEN

Acute pulmonary and systemic vasomotor changes induced by endotoxin in dogs have been related, at least in part, to the production of eicosanoids such as the vasoconstrictor thromboxane and the vasodilator prostacyclin. Steroids in high doses, in vitro, inhibit activation of phospholipase A2 and prevent fatty acid release from cell membranes to enter the arachidonic acid cascade. We, therefore, administered methylprednisolone (40 mg/kg) to dogs to see if eicosanoid production and the ensuing vasomotor changes could be prevented after administration of 150 micrograms/kg of endotoxin. The stable metabolites of thromboxane B2 (TxB2) and 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) were measured by radioimmunoassay. Methylprednisolone by itself did not alter circulating eicosanoids but when given 2.5 h before endotoxin not only failed to inhibit endotoxin-induced eicosanoid production but actually resulted in higher circulating levels of 6-keto-PGF1 alpha (P less than 0.05) compared with animals receiving endotoxin alone. Indomethacin prevented the steroid-enhanced concentrations of 6-keto-PGF1 alpha after endotoxin and prevented the greater fall (P less than 0.05) in systemic blood pressure and systemic vascular resistance with steroid plus endotoxin than occurred with endotoxin alone. Administration of methylprednisolone immediately before endotoxin resulted in enhanced levels (P less than 0.05) of both TxB2 and 6-keto-PGF1 alpha but with a fall in systemic blood pressure and vascular resistance similar to the animals pretreated by 2.5 h. In contrast to the early steroid group in which all of the hypotensive effect was due to eicosanoids, in the latter group steroids had an additional nonspecific effect. Thus, in vivo, high-dose steroids did not prevent endotoxin-induced increases in eicosanoids but actually increased circulating levels of TxB2 and 6-keto-PGF1 alpha with a physiological effect favoring vasodilation.


Asunto(s)
Ácidos Eicosanoicos/sangre , Endotoxinas/farmacología , Escherichia coli , Metilprednisolona/farmacología , Sistema Vasomotor/efectos de los fármacos , Animales , Perros , Hemodinámica/efectos de los fármacos , Indometacina/farmacología , Circulación Pulmonar/efectos de los fármacos
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