Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Zhonghua Yi Xue Za Zhi ; 103(17): 1334-1339, 2023 May 09.
Artículo en Chino | MEDLINE | ID: mdl-37150684

RESUMEN

Objective: To investigate the expression of glycolytic genes in immune cells and the changes of related immune cells in experimental autoimmune neuritis (EAN), and deepen the understanding of pathogenesis of EAN. Methods: Twenty-four male C57BL/6 mice (6-8 weeks old, 18-20 g) were divided into four groups according to the random number table method: control group (P0180-199 was replaced by PBS during modeling and mice were sacrificed on the 16th day), EAN mice were sacrificed on the 8th day after the end of modeling (EAN 8 d), EAN mice were sacrificed on the 16th day after the end of modeling (EAN 16 d), and EAN mice received drug intervention and were sacrificed on the 16th day after the end of modeling (2-DG was intraperitoneally injected since the day of the first immunization, 550 mg/kg; EAN 16 d+2-DG), with 6 rats in each group. The clinical symptoms and clinical scores were observed and recorded daily. At the end of the experiment, the mice were sacrificed under chloral hydrate anesthesia, and the serum, spleen, sciatic nerve and other tissues of each group were collected. The degree of inflammatory cell infiltration and demyelination of sciatic nerve were observed by hematoxylin and eosin (HE) staining and luxol fast blue (LFB) staining. Flow cytometry was used to detect the proportion of M1 macrophages, Th17 cells and Tregs cells. The mRNA expression levels of glycolysis-related genes (mTORC1, HIF1α, GLUT1 and LDHA) were detected by RT-PCR. Western blotting was used to detect the level of pan-lysine lactate in macrophages and sciatic nerve tissue. Results: The expression of glycolysis-related genes (mTORC1, HIF1α, GLUT1 and LDHA) in spleen M1 macrophages and sciatic nerve was significantly up-regulated in EAN 16 d group, compared with control, EAN 8 d and EAN 16 d+2-DG groups (all P<0.05). The relative pan-lysine lactate (pankla) expression level of spleen M1 macrophages (1.25±0.02) and sciatic nerve tissue (1.23±0.26) significantly increased in EAN 16 d group, compared with control, EAN 8 d and EAN 16 d+2-DG groups (M1 macrophages: 0.12±0.10, 1.07±0.12 and 0.42±0.07; sciatic nerve: 0.10±0.12, 0.87±0.20 and 0.36±0.05) (all P<0.05). The expression of glycolytic genes in splenic CD4+T cells showed an increasing trend, but there were no statistically significant differences among the groups, and the expression of glycolytic genes did not decrease significantly after 2-DG treatment (all P>0.05). The proportion of spleen M1 macrophages in the control group, EAN 8 d group, EAN 16 d group and EAN 16 d+2-DG group was 4.28±0.13, 7.54±0.25, 13.16±0.33 and 4.13±0.38 respectively, which was significantly higher in the EAN 16 d group (all P<0.05). The proportion of spleen Th17 cells in the four groups was 3.78±0.03, 8.24±0.55, 12.30±1.34 and 4.83±0.01, respectively, which was significantly higher in the EAN 16 d group (all P<0.05). The proportion of spleen Tregs cells in the four groups was 10.01±1.05, 7.54±0.70, 3.82±0.47 and 8.22±1.21, respectively, which was significantly lower in the EAN 16 d group (all P<0.05). Conclusions: The expression of glycolytic genes in splenic macrophages significantly increases during EAN, but not in CD4+T cells. The proportion of M1 macrophages and Th17 cells in spleen gradually increases, while the proportion of Tregs cells gradually decreases.


Asunto(s)
Neuritis Autoinmune Experimental , Ratas , Ratones , Masculino , Animales , Transportador de Glucosa de Tipo 1/metabolismo , Neuritis Autoinmune Experimental/tratamiento farmacológico , Neuritis Autoinmune Experimental/patología , Lisina/metabolismo , Lisina/uso terapéutico , Ratones Endogámicos C57BL , Nervio Ciático/metabolismo , Nervio Ciático/patología , Glucólisis
2.
Zhonghua Yi Xue Za Zhi ; 99(17): 1328-1331, 2019 May 07.
Artículo en Chino | MEDLINE | ID: mdl-31091581

RESUMEN

Objective: To investigate the relationship between preoperative evaluation, surgery and prognosis of microvascular decompression (MVD) for the treatment of hemifacial spasm (HFS). Methods: The clinical data of 128 HFS patients treated with MVD in the department of neurosurgery of Taizhou Hospital of Zhejiang Province were retrospectively analyzed. According to the SMC grading system, the patients were divided into general spasm group and severe spasm group, and the clinical characteristics, offending vessel, prognosis and surgical complications of the two groups were compared. Results: In the general spasm group,the age at MVD was (48.6±10.6) years, the disease duration was (4.2±3.3) years;while in the severe spasm group,the age at MVD was (51.8±9.9) years, the disease duration was (8.1±4.5) years;the differences of age and disease duration between the two groups were statistically significant (P<0.05).In the general spasm group, there were 41 cases in which the offending vessel were AICA, 21 cases were PICA, 1 case was VA, 63 cases were single offending vessel, and 7 cases were multiple offending vessels. In the severe spasm group, there were 29 cases in which the offending vessel were AICA, 13 cases were PICA, 2 cases were VA, the total of 44 cases were single offending vessel and 14 cases were multiple offending vessels.There was a significant difference in the proportion of multiple offending vessels in the two groups, and the difference was statistically significant (P<0.05).Patients in the two groups were followed up for 12 to 32 months after surgery, and the difference in effective rate and recurrence rate was not statistically significant (P>0.05).Some kinds of postoperative complications were different between the two groups, the incidence of postoperative delayed facial paralysis was statistically significant (P<0.05), and the other complications were not statistically significant (P>0.05). Conclusion: Compared with the general spasm group, the patients in the severe spasm group were older, with longer disease duration, higher probability of multiple offending vessels and higher incidence of postoperative delayed facial paralysis. Therefore, preoperative SMC grading is helpful for the evaluation and prediction of intraoperative and postoperative conditions, which is worthy of wide clinical application.


Asunto(s)
Parálisis Facial , Espasmo Hemifacial , Cirugía para Descompresión Microvascular , Adulto , Humanos , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento
3.
Zhonghua Yi Xue Za Zhi ; 99(13): 998-1002, 2019 Apr 02.
Artículo en Chino | MEDLINE | ID: mdl-30955312

RESUMEN

Objective: To investigate the clinical efficacy of superficial temporal artery -middle cerebral artery combined with encephalo-duro-arterio-myo-synangiosis (STA-MCA+EDAMS) and encephalo-duro-arterio-myo-synangiosis (EDAMS) in the treatment of adult moyamoya disease. Methods: The clinical data of 47 adult patients with moyamoya disease who received vascular reconstruction in the Department of Neurosurgery of Taizhou Hospital of Zhejiang Province from January 2014 to January 2018 were retrospectively analyzed. Among them, 21 patients received EDAMS alone (EDAMS group, 14 patients with hemorrhagic moyamoya disease, 7 patients with ischemic moyamoya disease), 26 patients received STA-MCA combined with EDAMS (STA-MCA+EDAMS group, 17 patients with hemorrhagic moyamoya disease, 9 patients with ischemic moyamoya disease). Cerebral hemodynamics at 1 day before surgery and 3 and 6 months after surgery were compared. The clinical efficacy and postoperative complications of the two methods were compared at 3 and 6 months postoperatively in hemorrhagic and ischemic types. Results: For hemorrhagic moyamoya disease, the remission rate (94.1%) at 6 months after surgery in the STA-MCA + EDAMS group was higher than that in the EDAMS group (57.1%), and the difference was statistically significant (P<0.05). The CBF and CBV in the STA-MCA+EDAMS group were higher than those in the EDAMS group at 3 and 6 months after operation, and the MTT and TPP were lower than those in the EDAMS group, but there was no significant difference between the two groups (all P>0.05). For hemorrhagic moyamoya disease and ischemic moyamoya disease, the total incidence of postoperative complications of the two surgical methods was different, but the difference was not statistically significant (both P>0.05). Conclusion: Superficial temporal artery -middle cerebral artery combined with encephalo-duro- arterio-myo-synangiosis (STA-MCA+EDAMS) and encephalo-duro-arterio-myo-synangiosis (EDAMS) can significantly improve neurological function and cerebral hemodynamics in adult moyamoya disease patients with high safety.


Asunto(s)
Revascularización Cerebral , Enfermedad de Moyamoya , Adulto , Humanos , Arteria Cerebral Media , Enfermedad de Moyamoya/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
4.
Int J Immunopathol Pharmacol ; 25(4): 871-81, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23298478

RESUMEN

MicroRNAs (miRNAs) play important roles in the regulation of gene expressions. Aberrant expression of miRNAs is implicated in a variety of biological and pathological processes, including the tumorigenesis of glioma (GM). Though the molecular mechanisms of protein kinase B (AKT) survival signal have been comprehensively explored, the role of miR-149 in glioblastoma (GBM) and its regulation on AKT signaling have not yet been ascertained. The present study aimed to elucidate the role and molecular mechanisms of miR-149 in U251 GM cells. Using a gain-of-function approach, we investigated the effects of lentivirus-mediated overexpression of miR-149 on the expression of phosphated-AKT1 (p-AKT1), proliferating cell nuclear antigen (PCNA), matrix metallopeptidase-2 (MMP-2) and CyclinD1 in U251 cells and nude mice subcutaneous xenograft tumors by Real-time PCR, Western blot and immunohistochemical assays. Proliferative activities indicated by MTT assay, invasive potential by Transwell and cycle distribution by flow cytometry were carried out for functional analysis of U251 cells after infection with miR-149 mimic. As a consequence, miR-149 inhibited the expression of p-AKT1, PCNA, CyclinD1 and MMP-2, reduced the proliferative activities and invasive potential, and induced cycle arrest in G0/G1 phase in U251 cells. In conclusion, our findings show that miR-149 as tumor suppressor may be involved in the proliferation and invasion of GM cells via blockade of the AKT1 signaling, and be considered as a candidate target for the treatment of cancer.


Asunto(s)
Neoplasias Encefálicas/patología , Proliferación Celular , Glioma/patología , MicroARNs/fisiología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Transducción de Señal , Neoplasias Encefálicas/terapia , Ciclo Celular , Línea Celular Tumoral , Movimiento Celular , Ciclina D1/análisis , Glioma/terapia , Humanos , Inmunohistoquímica , Lentivirus/genética , MicroARNs/genética , Invasividad Neoplásica , Fosfatidilinositol 3-Quinasas/fisiología , Proteínas Proto-Oncogénicas c-akt/fisiología
5.
Am J Physiol Cell Physiol ; 281(1): C17-23, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11401823

RESUMEN

It was previously determined that ANG II and phorbol esters inhibit Kv current in neurons cultured from newborn rat hypothalamus and brain stem in a protein kinase C (PKC)- and Ca2+-dependent manner. Here, we have further defined this signaling pathway by investigating the roles of "physiological" activators of PKC and different PKC isozymes. The cell-permeable PKC activators, diacylglycerol (DAG) analogs 1,2-dioctanoyl-sn-glycerol (1 micromol/l, n = 7) and 1-oleoyl-2-acetyl-sn-glycerol (1 micromol/l, n = 6), mimicked the effect of ANG II and inhibited Kv current. These effects were abolished by the PKC inhibitor chelerythrine (1 micromol/l, n = 5) or by chelation of internal Ca2+ (n = 8). PKC antisense (AS) oligodeoxynucleotides (2 micromol/l) against Ca2+-dependent PKC isoforms were applied to the neurons to manipulate the endogenous levels of PKC. PKC-alpha-AS (n = 4) treatment abolished the inhibitory effects of ANG II and 1-oleoyl-2-acetyl-sn-glycerol on Kv current, whereas PKC-beta-AS (n = 4) and PKC-gamma-AS (n = 4) did not. These results suggest that the angiotensin type 1 receptor-mediated effects of ANG II on neuronal Kv current involve activation of PKC-alpha.


Asunto(s)
Angiotensina II/fisiología , Isoenzimas/metabolismo , Neuronas/metabolismo , Canales de Potasio con Entrada de Voltaje , Canales de Potasio/metabolismo , Proteína Quinasa C/metabolismo , Alcaloides , Animales , Benzofenantridinas , Calcio/metabolismo , Células Cultivadas , Canales de Potasio de Tipo Rectificador Tardío , Diglicéridos/farmacología , Inhibidores Enzimáticos/farmacología , Immunoblotting , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Neuronas/efectos de los fármacos , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/metabolismo , Técnicas de Placa-Clamp , Fenantridinas/farmacología , Bloqueadores de los Canales de Potasio , Canales de Potasio/efectos de los fármacos , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/genética , Proteína Quinasa C-alfa , Ratas , Ratas Sprague-Dawley , Receptores de Angiotensina/metabolismo
6.
Am J Physiol Endocrinol Metab ; 280(4): E554-61, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11254461

RESUMEN

The present study was conducted to determine the effect of chronic administration of the long-acting beta(2)-adrenergic agonist clenbuterol on rats that are genetically prone to insulin resistance and impaired glucose tolerance. Obese Zucker rats (fa/fa) were given 1 mg/kg of clenbuterol by oral intubation daily for 5 wk. Controls received an equivalent volume of water according to the same schedule. At the end of the treatment, rats were catheterized for euglycemic-hyperinsulinemic (15 mU insulin. kg(-1). min(-1)) clamping. Clenbuterol did not change body weight compared with the control group but caused a redistribution of body weight: leg muscle weights increased, and abdominal fat weight decreased. The glucose infusion rate needed to maintain euglycemia and the rate of glucose disappearance were greater in the clenbuterol-treated rats. Furthermore, plasma insulin levels were decreased, and the rate of glucose uptake into hindlimb muscles and abdominal fat was increased in the clenbuterol-treated rats. This increased rate of glucose uptake was accompanied by a parallel increase in the rate of glycogen synthesis. The increase in muscle glucose uptake could not be ascribed to an increase in the glucose transport protein GLUT-4 in clenbuterol-treated rats. We conclude that chronic clenbuterol treatment reduces the insulin resistance of the obese Zucker rat by increasing insulin-stimulated muscle and adipose tissue glucose uptake. The improvements noted may be related to the repartitioning of body weight between tissues.


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Clenbuterol/farmacología , Resistencia a la Insulina/fisiología , Obesidad/fisiopatología , Animales , Glucemia/análisis , Peso Corporal/efectos de los fármacos , Femenino , Glucosa/metabolismo , Glucógeno/biosíntesis , Insulina/sangre , Músculo Esquelético/metabolismo , Obesidad/patología , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Zucker , Triglicéridos/metabolismo
7.
Biomed Chromatogr ; 13(1): 83-5, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10191951

RESUMEN

A gas chromatographic method for monitoring diacetyl guanfubase A in plasma is described. The procedure involved a single solvent extraction of drug from rabbit plasma into ethyl acetate with guanfubase A as an internal standard. The extract was analyzed subsequently on a gas chromatograph equipped with a hydrogen flame ionization detector. The recovery was 86.43% +/- 6.90% (+/- SD); the RSD of within-day and between-day was 2.81%-5.26% and 5.22%-8.24%, respectively; the regression line was linear over the concentration range of 25-200 micrograms/mL, the limit of detection was 10 micrograms/mL. No endogeneous interference was found in chromatograms of the biological samples. This method was applied to the pharmacokinetic study of diacetyl guanfubase A in rabbits.


Asunto(s)
Alcaloides/sangre , Antiarrítmicos/sangre , Alcaloides/farmacocinética , Animales , Antiarrítmicos/farmacocinética , Cromatografía de Gases , Conejos , Estándares de Referencia , Reproducibilidad de los Resultados
8.
Diabetologia ; 42(3): 310-6, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10096783

RESUMEN

We have recently demonstrated that insulin activates farnesyltransferase (FTase) and thereby increases the amounts of cellular farnesylated p21Ras in 3T3-L1 fibroblasts, adipocytes and vascular smooth muscle cells. We postulated that hyperinsulinaemia might considerably increase the the cellular pool of farnesylated p21Ras available for activation by other growth factors. To examine the role of in vivo hyperinsulinaemia in regulating farnesylated p21Ras, we measured the amounts of farnesylated p21Ras in tissues of hyperinsulinaemic animals. Liver, aorta, and skeletal muscle of ob/ob mice, and mice made obese and hyperinsulinaemic by injection of gold-thioglucose contained greater amounts of farnesylated p21Ras than tissues of their lean normoinsulinaemic counterparts. Similarly, farnesylated p21Ras was increased (67 vs. 35 % in control animals, p<0.01) in the livers of hyperinsulinaemic Zucker rats (fa/fa). Reduction of hyperinsulinaemia by exercise training (2 h/day for 7-8 weeks) resulted in decreases in the amounts of farnesylated p21Ras in these animals. Increased farnesylated p21Ras in hyperinsulinaemic animals reflected increasing increments in the activity of FTase in ob/ob mice (2-fold increase) and fa/fa Zucker rats (3.5-fold increase), while the total amounts of Ras proteins remained unchanged. In contrast to insulin-resistant hyperinsulinaemic animals, denervated insulin-resistant rat soleus muscle (in the presence of normoinsulinaemia) showed normal amounts of farnesylated p21Ras. In summary, these data confirm increased amounts of farnesylated p21Ras in tissues of hyperinsulinaemic animals.


Asunto(s)
Transferasas Alquil y Aril/metabolismo , Hiperinsulinismo/metabolismo , Hígado/metabolismo , Músculo Esquelético/metabolismo , Músculo Liso Vascular/metabolismo , Obesidad/metabolismo , Prenilación de Proteína , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Células 3T3 , Animales , Aurotioglucosa , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Clenbuterol/farmacología , Farnesiltransferasa , Femenino , Hiperinsulinismo/inducido químicamente , Insulina/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Desnervación Muscular , Músculo Esquelético/inervación , Obesidad/genética , Obesidad/fisiopatología , Condicionamiento Físico Animal , Prenilación de Proteína/efectos de los fármacos , Ratas , Ratas Zucker
9.
Yi Chuan Xue Bao ; 25(6): 478-84, 1998 Dec.
Artículo en Chino | MEDLINE | ID: mdl-10465893

RESUMEN

The polymorphics of two pericentric (GT)n sequences on the long arm of human chromosome 21 have been analyzed after PCR amplification, PAGE and Ag-staining for the first time in 50 Chinese Han people, and were used to detect meiotic origin of the extra chromosome 21 in Down syndromes. Six and 5 alleles were found in Chinese Han people for D21S215 and D21S120, respectively, with observed heterozygosities of 0.68 and polymorphic information content PIC, 0.67 and 0.65. For 17 Down syndromes whose parental origin of the extra chromosome 21 were known, meiotic origin of the extra chromosome 21 were determined in 16 cases, with 7 and 4 maternal meiosis I and II nondisjunction, 2 and 3 paternal meiosis I and II, respectively. The possible biological significance of the study on origin of the extra chromosome 21 has been discussed.


Asunto(s)
Cromosomas Humanos Par 21 , Síndrome de Down/genética , Marcadores Genéticos , Meiosis , Femenino , Humanos , Masculino , Polimorfismo Genético
10.
Sheng Li Xue Bao ; 49(1): 73-8, 1997 Feb.
Artículo en Chino | MEDLINE | ID: mdl-9812836

RESUMEN

The role of the ATP-sensitive potassium channel in arrhythmogenesis is not clearly understood. Cellular K+ loss and accumulation of [K+]o may contribute to genesis of malignant ventricular arrhythmia during myocardial ischemia. In the present study, acute hypoxia simply caused a partial decrease in K+ efflux at normal [K+]o, which was not sensitive to glibenclamide (5 x 10(-3) mmol/L). However, at a higher concentration of [K+]o (10.8 mmol/L), the outward K+ current increased dramatically after 10 min hypoxia, which was accompanied with an irreversible hypercontracture and eventual death of the cell. The I-V relation was linear with increasing repolarization, which was blocked by glibenclamide, an antagonist of ATP-sensitive potassium channel. The results suggest that the increased K+ current is ATP-sensitive and is facilitated by accumulation of the [K+]o.


Asunto(s)
Miocardio/metabolismo , Canales de Potasio/metabolismo , Potasio/metabolismo , Adenosina Trifosfato/antagonistas & inhibidores , Adenosina Trifosfato/fisiología , Animales , Transporte Biológico Activo , Hipoxia de la Célula , Femenino , Gliburida/farmacología , Cobayas , Hipoglucemiantes/farmacología , Masculino , Miocardio/citología
11.
Scanning ; 18(8): 562-6, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8946771

RESUMEN

Three-dimensional confocal imaging of polymer samples was achieved by the use of two-photon excited fluorescence in both positive and negative contrast modes. The fluorophore was a new and highly efficient two-photon induced upconverter, resulting in improved signal strength at low pumping power. Because of the relatively long wavelength of the excitation source (798 nm from a mode-locked Ti:Sapphire laser), this technique shows a larger penetration depth into the samples than provided by conventional single-photon fluorescence confocal microscopy. Single-photon and two-photon images of the same area of each sample show significant differences. The results suggest the possibility of using two-photon confocal microscopy, in conjunction with highly efficient fluorophores, as a tool to study the surface, interface, and fracture in material science applications.


Asunto(s)
Colorantes Fluorescentes/síntesis química , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Estilbenos/síntesis química , Procesamiento de Imagen Asistido por Computador , Rayos Láser , Polímeros
13.
Sheng Li Xue Bao ; 47(5): 435-40, 1995 Oct.
Artículo en Chino | MEDLINE | ID: mdl-8711506

RESUMEN

When the conventional whole cell recording technique is used to study the inward calcium current in cardiac cells, the "Run down" phenomenon of calcium channel would prevent sufficient time of recording desirable for adequate experimental analysis. The "Run down" phenomenon could be minimized by using nystatin-whole cell recording technique in isolated guinea-pig ventricular cells. The inward L-type calcium current could be maintained at a steady level for up to more than 100 min, showing the presence of an endogenous steady calcium ion buffering mechanism. With nystatin-whole cell recording, the L-type calcium current after 10 min acute hypoxia (Po2 4 +/- 0.7 kPa) was inhibited (peak amplitude decreased) and the I-V relation was shifted upward. The inward calcium current showed no recovery after 10 min reoxygenation. The peak amplitude was lower than that of the control. The results suggested that the decrease of action potential duration (APD) under acute hypoxia was not only due to increase of outward potassium current, but also a decrease of inward calcium current. All these phenomena may be related to some inhibition of phosphorylation of the L-type calcium channel in the cardiac cells under hypoxia.


Asunto(s)
Calcio/metabolismo , Miocardio/metabolismo , Miocardio/patología , Potenciales de Acción , Animales , Canales de Calcio , Hipoxia de la Célula , Femenino , Cobayas , Masculino , Técnicas de Placa-Clamp
14.
Toxicology ; 97(1-3): 93-104, 1995 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-7716796

RESUMEN

The cardiotoxicity of emetine continues to be a significant clinical problem. The purpose of this study was to investigate the effect of several mechanistic interventions, including ICRF-187, an iron-chelating agent which protects against doxorubicin toxicity, atropine, and fructose-1,6-bisphosphate (FBP) on the toxicity of emetine in our isolated, perfused rat heart model. The model includes functional, electrocardiographic, and biochemical determinations in the same preparation. Atropine and ICRF-187 had no effect on the time needed for emetine to induce ventricular asystole, while FBP significantly increased this time. Administration of 47 microM atropine, 300 microM FBP, or 1 mM FBP decreased the release of lactate dehydrogenase (LDH) into the coronary effluent, while ICRF-187 had no effect. These pharmacological interventions variably changed the amplitude of the biphasic response of the coronary flow to emetine. Finally, FBP was very effective in slowing the rate of QRS-waveform degeneration in the perfused hearts. Emetine caused PR- and QRS-prolongation which was not altered by FBP.


Asunto(s)
Emetina/toxicidad , Fructosadifosfatos/farmacología , Corazón/efectos de los fármacos , Animales , Atropina/farmacología , Circulación Coronaria/efectos de los fármacos , Electrocardiografía , L-Lactato Deshidrogenasa/metabolismo , Masculino , Perfusión , Ratas , Ratas Sprague-Dawley , Razoxano/farmacología
15.
Toxicol In Vitro ; 9(3): 219-29, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20650082

RESUMEN

Emetine is an old drug which is used primarily as a emetic in ipecac syrup and as an alternative amoebicide. The major problem with emetine is that chronic use causes severe cardiotoxicity. In order to explore the mechanism of emetine cardiotoxicity, simultaneous recordings of mechanical activity and electrocardiograms, and biochemical assays were performed on male Sprague-Dawley rat hearts perfused by the Langendorff technique. Emetine was perfused constantly at concentrations of 19 or 37 mum for 10 min. All of the effects of emetine were concentration dependent. The most significant toxicological effect was the large amounts of LDH which appeared in the coronary effluent. A significant degree of injury to the cardiac plasma membrane is indicated by this observation, since LDH normally is an intracellular enzyme. Such damage to the membrane might accumulate and lead to the chronic, cumulative cardiotoxicity observed clinically with emetine. The pharmacological effects of emetine perfusion included decreased contractility which occurred concurrently with P-R interval prolongation, QRS duration prolongation, and degeneration of the QRS waveform. Coronary flow increased early during emetine perfusion, but then dropped to below control levels. The atria were more delayed in their response to emetine and in their recovery following emetine than were the ventricles. The simultaneous measurement of several parameters is a useful technique for the study of cardiac toxicity.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA