RESUMEN
AIM: The anatomy of the region between the vagina and anal canal plays an essential role when performing a proctectomy for low-lying tumours. However, the anatomical characteristics of this area remain unclear. The purpose of the present study was to clarify the configuration, and both lateral and inferior extensions, of the muscle bundles in the anorectal anterior wall in females. METHODS: Using cadaveric specimens, macroscopic anatomical and histological evaluations were conducted at the anatomy department of our institute. Macroscopic anatomical specimens were obtained from six female cadavers. Histological specimens were obtained from eight female cadavers. RESULTS: The smooth muscle fibres of the internal anal sphincter and longitudinal muscle extended anteriorly in the anorectal anterior wall of females and the muscle bundles showed a convergent structure. The anterior extending smooth muscle fibres merged into the vaginal smooth muscle layer, distributed subcutaneously in the vaginal vestibule and perineum and spread to cover the anterior surface of the external anal sphincter and the levator ani muscle. Relatively sparse space was observed in the region anterolateral to the rectum on histological analysis. CONCLUSION: Smooth muscle fibres of the rectum and vagina are intermingled in the median plane, and there is relatively sparse space in the region anterolateral to the rectum. Therefore, when detaching the anorectal canal from the vagina during proctectomy, an approach from both the lateral sides should be used.
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Canal Anal/anatomía & histología , Músculo Liso/anatomía & histología , Proctectomía/métodos , Recto/anatomía & histología , Vagina/anatomía & histología , Cadáver , Femenino , HumanosRESUMEN
Understanding the surgical anatomy is the key to reducing surgical invasiveness especially in the upper mediastinal dissection for esophageal cancer, which is supposed to have a significant impact on curability and morbidity. However, there is no theoretical recognition regarding the surgical anatomy required for esophagectomy, although the surgical anatomy in abdominal digestive surgery has been developed on the basis of embryological findings of intestinal rotation and fusion fascia. Therefore, we developed a hypothesis of a 'concentric-structured model' of the surgical anatomy in the upper mediastinum based on human embryonic development. This model was characterized by three factors: (1) a concentric and symmetric three-layer structure, (2) bilateral vascular distribution, and (3) an 'inter-layer potential space' composed of loose connective tissue. The concentric three-layer structure consists of the 'visceral layer', the 'vascular layer', and the 'parietal layer': the visceral layer containing the esophagus, trachea, and recurrent laryngeal nerves as the central core, the vascular layer of major blood vessels surrounding the visceral core to maintain the circulation, and the parietal layer as the outer frame of the body. The bilateral vascular distribution consists of the inferior thyroid arteries and bronchial arteries originating from the bilateral dorsal aortae in an embryo. This bilateral vascular distribution may be related to the formation of the proper mesentery of the esophagus and frequent lymph node metastasis observed in the visceral layer around recurrent laryngeal nerves. The three concentric layers are bordered by loose connective tissue called the 'inter-layer potential space'. This inter-layer potential space is the fundamental factor of our concentric-structured model as the appropriate surgical plane of dissection. The peripheral blood vessels, nerves, and lymphatics transition between each layer, thereby penetrating this loose connective tissue forming the inter-layer potential space. Recurrent laryngeal nerves also transition from the vascular layer after branching off from the vagal nerves and then ascend consistently in the visceral layer. We investigated the validity of this concentric-structured model, confirming the intraoperative images and the surgical outcomes of thoracoscopic esophagectomy in a prone position (TSEP) before and after the introduction of this hypothetical anatomy model. A total of 226 patients with esophageal cancer underwent TSEP from January 2015 to December 2016. After the introduction of this model, the surgical outcomes in 105 patients clearly improved for the operation time of the thoracoscopic procedure (160 min vs. 182 min, P = 0.01) and the incidence of recurrent laryngeal nerve palsy (19.0% vs. 36.4%, P = 0.004). Moreover, we were able to identify the concentric and symmetric layer structure through surgical dissection along the inter-layer potential space between the visceral and vascular layers ('viscero-vascular space') in all 105 cases after introduction of the hypothetical model. The concentric-structured model based on embryonic development is clinically beneficial for achieving less-invasive esophagectomy by ensuring a theoretical understanding of the surgical anatomy in the upper mediastinum.
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Neoplasias Esofágicas/cirugía , Esofagectomía/métodos , Escisión del Ganglio Linfático/métodos , Mediastino/anatomía & histología , Modelos Teóricos , Toracoscopía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Mediastino/cirugía , Persona de Mediana EdadRESUMEN
PURPOSE: Patients with a shoulder disorder often complain of pain on the anterior or lateral aspect of the shoulder. Such pain has been thought to originate from the suprascapular nerve. However, taking into consideration the distinctive course of the axillary nerve, the axillary nerve is likely to supply branches to the structure around the shoulder joint. This study was conducted to clarify the division, course, and distribution of the branches which originate from the axillary nerve and innervate structures around the shoulder joint. METHODS: The division, course, and distribution of the branches which originate from the axillary nerve and innervate structures around the shoulder joint were examined macroscopically by dissecting 20 shoulders of 10 adult Japanese cadavers. RESULTS: The thin branches from the anterior branch of the axillary nerve were distributed to the subacromial bursa and the area around the long head of the biceps tendon. The branches from the main trunk of the axillary nerve or the branch to the teres minor muscle were distributed to the infero-posterior part of the shoulder joint. CONCLUSION: The pain on the anterior or lateral aspect of the shoulder, which has been thought to originate from the suprascapular nerve, might be related to the thin branches which originate from the axillary nerve and innervate the subacromial bursa and the area around the long head of the biceps tendon. CLINICAL RELEVANCE: These results would be useful to consider the cause of the shoulder pain or to prevent the residual pain after the biceps tenodesis.
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Axila/inervación , Bolsa Sinovial/inervación , Articulación del Hombro/inervación , Tendones/inervación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , MasculinoRESUMEN
BACKGROUND: The structure and function of the serratus anterior muscle are partitioned into three parts. If the morphological characteristics in each part can be demonstrated in more detail, the cause of dysfunction will probably be identifiable more accurately. The purpose of this study was to demonstrate the details of the structure and innervation in each part of the serratus anterior muscle. MATERIALS AND METHODS: This macroscopic anatomic study was conducted using ten sides from five cadavers. The structure and innervation in each part of this muscle were examined. RESULTS: In the superior part, the independent branch was divided from a branch innervating the levator scapulae muscle. In the middle part, the long thoracic nerve descended on one-third of the anterior region between the origin and insertion. In the inferior part, the long thoracic nerve which ramified into many branches and branches from the intercostal nerves were distributed on all sides. CONCLUSION: This study demonstrated that the innervation of the serratus anterior muscle was different in each part. The difference indicates that the superior part has an intimate relation with the levator scapulae muscle while the middle and inferior parts could be the actual serratus anterior muscle. Moreover, the distribution of branches from the intercostal nerves shows that the inferior part has a connection with some trunk elements. Understanding these characteristics of innervation is useful to identify the cause of dysfunction. In addition, we assert that the constant distribution of branches from the intercostal nerves is significant for the morphology.
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Músculo Esquelético/anatomía & histología , Escápula/anatomía & histología , Escápula/inervación , Nervios Torácicos/anatomía & histología , Pared Torácica/anatomía & histología , Pared Torácica/inervación , Cadáver , Femenino , Humanos , Masculino , Costillas/anatomía & histología , Costillas/inervaciónRESUMEN
The Kansai BNCT Medical Center has a cyclotron based epithermal neutron source for clinical Boron Neutron Capture Therapy. The system accelerates a proton to an energy of 30 MeV which strikes a beryllium target producing fast neutrons which are moderated down to epithermal neutrons for BNCT use. While clinical studies in the past have shown BNCT to be highly effective for malignant melanoma of the skin, to apply BNCT for superficial lesions using this system it is necessary to shift the thermal neutron distribution so that the maximum dose occurs near the surface. A dose distribution shifter was designed to fit inside the collimator to further moderate the neutrons to increase the surface dose and reduce the dose to the underlying normal tissue. Pure polyethylene was selected, and a Monte Carlo simulation was performed to determine the optimum thickness of the polyethylene slab. Compared with the original neutron beam, the shifter increased the thermal neutron flux at the skin by approximately 4 times. The measured and simulated central axis depth distribution and off axis distribution of the thermal neutron flux were found to be in good agreement. Compared with a 2 cm thick water equivalent bolus, a 26% increase in the thermal neutron flux at the surface was obtained, which would reduce the treatment time by approximately 29%. The DDS is a safe, simple and an effective tool for the treatment of superficial tumours for BNCT if an initially fast neutron beam requires moderation to maximise the thermal neutron flux at the tissue surface.
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Terapia por Captura de Neutrón de Boro , Neoplasias , Humanos , Método de Montecarlo , Neutrones , Fantasmas de ImagenRESUMEN
The authors report their latest results on II-VI intersubband all-optical switches in which the 10 dB absorption saturation energy is lowered to ~2.0-2.2 pJ for 1.55-1.58 mum by decreasing the thickness of the active layer and increasing the refractive index difference between the core layer and the cladding layers in waveguides. Such low saturation energies greatly improve the switching performance. <7 pJ pump energy at 1520 nm is sufficient for realizing 10 dB switching operation at 1566 nm (switching energy: ~0.7 pJ/dB). To the best of our knowledge, these switching energy and saturation energy values are the lowest reported ones for such ultrafast intersubband all-optical switches at telecommunication wavelengths.
RESUMEN
Retinoids induce apoptosis and differentiation of hepatocellular carcinoma (HCC) cells and are used clinically in the chemoprevention of HCC. We have shown previously that hepatocarcinogenesis is accompanied by accumulation of full-length retinoid X receptor alpha (RXRalpha), although the underlying mechanisms and biological implications have remained unclear. The present studies were based on the finding that the accumulated full-length RXRalpha was phosphorylated at serine/threonine residues both in all human HCC tissues examined and in human HCC-derived HuH7 cells. Phosphorylation at serine 260 of RXRalpha, a consensus site of mitogen-activated protein kinase, was closely linked to its retarded degradation, low transactivating activity, and the promotion of cancer cell growth. There was no genomic mutation in the RXRalpha gene, and abrogation of phosphorylation by mitogen-activated protein kinase-specific inhibitors restored the degradation of RXRalpha in an RXR ligand-dependent manner. These results suggest that phosphorylation of RXRalpha may interfere with its metabolism and signaling in human HCC, which could lead to growth promotion of these tumors.
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Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Receptores de Ácido Retinoico/metabolismo , Factores de Transcripción/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , División Celular/fisiología , Humanos , Ligandos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Mutagénesis Sitio-Dirigida , Fosforilación , Receptores de Ácido Retinoico/antagonistas & inhibidores , Receptores de Ácido Retinoico/genética , Receptores X Retinoide , Serina/metabolismo , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Activación Transcripcional/fisiología , TransfecciónRESUMEN
We have manipulated the chick limb bud by dorsoventrally inverting the ectoderm, by grafting the AER to the dorsal or ventral ectoderm and by insertion of an FGF-4 soaked heparin bead into the mesoderm. After dorso-ventral reversal of the ectoderm, Wnt-7a expression is autonomous from an early stage of limb development in the original dorsal ectoderm. Exogenous FGF-4 causes ectopic Wnt-7a expression and induces ectopic Shh. In addition, exogenous FGF-4 increases the thickness of cartilages and also shortens them, and both Bmp-2 and Bmp-4 may mediate this effect. The ectoderm outside the AER can regulate not only the dorso-ventral polarity of the underlying mesenchyme cells but also the cartilage formation, and both Bmp-2 and Bmp-4 may mediate this control.
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Proteínas Aviares , Proteínas Morfogenéticas Óseas/genética , Factores de Crecimiento de Fibroblastos/farmacología , Esbozos de los Miembros/embriología , Esbozos de los Miembros/metabolismo , Proteínas/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/farmacología , Transactivadores , Factor de Crecimiento Transformador beta , Animales , Tipificación del Cuerpo/efectos de los fármacos , Proteína Morfogenética Ósea 2 , Proteína Morfogenética Ósea 4 , Cartílago/efectos de los fármacos , Cartílago/embriología , Embrión de Pollo , Ectodermo/efectos de los fármacos , Ectodermo/metabolismo , Factor 4 de Crecimiento de Fibroblastos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Proteínas Hedgehog , Hibridación in Situ , Esbozos de los Miembros/efectos de los fármacos , Esbozos de los Miembros/cirugía , Factores de Tiempo , Proteínas WntRESUMEN
Interleukin-18 binding protein is a novel glycoprotein that we successfully cloned and expressed. First, murine interleukin-18 binding protein was purified from the sera of mice with endotoxin shock using ligand affinity chromatography. The murine interleukin-18 binding protein cDNA was cloned after RT-PCR using mixed primer pair sequences based on partial murine interleukin-18 binding protein amino acid sequence analysis. Subsequently, human interleukin-18 binding protein cDNA was cloned from cDNA libraries of normal human liver using murine interleukin-18 binding protein cDNA as a probe. Next, we transiently expressed recombinant human and murine interleukin-18 binding proteins in COS-1 cells and purified them from culture supernatants. Both recombinant interleukin-18 binding proteins did not exhibit species specificity and prevented interleukin-18 binding to its receptor. In addition, they inhibited interleukine-18 dependent IFN-gamma production from KG-1 cells effectively. These results suggest that the interleukin-18 binding protein may possess interleukine-18 antagonist activity.
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Glicoproteínas/genética , Interleucina-18/metabolismo , Proteínas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células CHO , Células COS , Línea Celular , Clonación Molecular , Cricetinae , ADN Complementario , Expresión Génica , Glicoproteínas/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular , Ratones , Datos de Secuencia Molecular , Proteínas/metabolismo , Homología de Secuencia de AminoácidoRESUMEN
We developed a new system to measure the intracellular Ca2+ concentration in the deep region of the central nervous system with a single optical fiber (300 microns in diameter), used for both excitation and detection of the fluorescence of previously loaded fura-2. With this system, a brain region loaded with fura-2 was illuminated by a rotating disc bearing three different interference filters of 340, 360 and 380 nm at a rate of 600 rpm. The emitted fluorescence was collected by the same fiber connected to a photomultiplier whose output was fed into a computer which regulates the timing of illumination and detection. The time course of the change in the fluorescence due to 340, 360 or 380 nm excitation was measured simultaneously at the maximum sampling rate of 10 points/s. Ratios of fluorescence intensities were obtained after the experiment. After confirming that this system was sensitive enough to detect the change of intracellular Ca2+ concentration in cultured hippocampal neurons and hippocampal slices during depolarization by high potassium medium (50 mM), we applied this system to anesthetized rats. In the hippocampus preloaded with fura-2, characteristic changes in fluorescence intensities ascribed to an increase in intracellular Ca2+ concentration were detected after asphyxia. The system is potentially useful for investigating the physiological and pathological roles of Ca2+ in the brain.
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Calcio/análisis , Hipocampo/química , Neuronas/química , Espectrometría de Fluorescencia/instrumentación , Anestesia , Animales , Calcio/metabolismo , Calcio/fisiología , Tecnología de Fibra Óptica , Fura-2 , Hipocampo/citología , Hipocampo/metabolismo , Neuronas/metabolismo , Fibras Ópticas , Ratas , Ratas WistarRESUMEN
1 The effects of the immunosuppressant drugs cyclosporin A and tacrolimus (FK506) on nitric oxide synthesis were examined in a murine macrophage cell line (J774) and rat vascular smooth muscle cells (VSMC) in culture for 24 and 48 h, respectively. 2 Cyclosporin A (0.01-10 microM) inhibited by up to 90% accumulation of nitrite induced by lipopolysaccharide (LPS) in both cell lines, but FK506 (0.01-10 microM) had a weaker effect on nitrite accumulation in these cells. Cyclosporin A and FK506 (at 1 microM) also significantly inhibited nitrite production induced by recombinant murine interferon-gamma (rIFNgamma) and recombinant murine interleukin-1beta (rIL-1beta) in J774 and VSMC, respectively. 3 In J774 cells, cyclosporin A (but not FK506) at 1 microM was inhibitory when co-incubated with the inducing agents but not when the cells were treated with the immunosuppressant before or after the inducer. In VSMC, nitrite production was inhibited by co-incubation of cyclosporin A or FK506 with the inducer, or when the immunosuppressants were pre-incubated with cells. In contrast, N-monomethyl L-arginine (NMMA) abolished nitrite production when incubated with either cell type during or after addition of inducing agent, but not if cells were preincubated with NMMA. 4 RNA extracted from treated J774 and VSMC was subjected to reverse transcription-polymerase chain reaction (RT-PCR). Cyclosporin A, but not FK506, suppressed expression of mRNA for NOS2 in a concentration-dependent manner when co-incubated with LPS. 5 The fact that the potency difference between cyclosporin A and FK506 for NO suppression is the opposite to that for inhibition of interleukin-2 generation suggests that the immunosuppressants act in J774 macrophages and VSMC through intracellular mechanisms that differ from those elucidated in T-cells. Cyclosporin A suppresses NOS2 gene transcription, but FK506 acts post-transcriptionally to suppress NO generation in VSMC. 6 Taken together the present data suggest that therapeutic concentrations of cyclosporin A, but not FK506, might well suppress NO production, but FK506 would not have this effect. Suppression of NO might contribute to the side effects of hypertension and nephrotoxicity associated with long-term use of cyclosporin A to prevent transplant rejection.
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Ciclosporina/farmacología , Inhibidores Enzimáticos/farmacología , Inmunosupresores/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/biosíntesis , Tacrolimus/farmacología , Animales , Southern Blotting , Línea Celular , Depresión Química , Interferón gamma/farmacología , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Masculino , Ratones , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/enzimología , Óxido Nítrico Sintasa de Tipo II , Nitritos/metabolismo , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
The SulA protein is a cell division inhibitor in Escherichia coli, and is specifically degraded by Lon protease. To study the recognition site of SulA for Lon, we prepared a mutant SulA protein lacking the C-terminal 8 amino acid residues (SA8). This deletion protein was accumulated and stabilized more than native SulA in lon(+) cells in vivo. Moreover, the deletion SulA fused to maltose binding protein was not degraded by Lon protease, and did not stimulate the ATPase or peptidase activity of Lon in vitro, probably due to the much reduced interaction with Lon. A BIAcore study showed that SA8 directly interacts with Lon. These results suggest that SA8 of SulA was recognized by Lon protease. The SA8 peptide, KIHSNLYH, specifically inhibited the degradation of native SulA by Lon protease in vitro, but not that of casein. A mutant SA8, KAHSNLYH, KIASNLYH, or KIHSNAYH, also inhibited the degradation of SulA, while such peptides as KIHSNLYA did not. These results show that SulA has the specified rows of C-terminal 8 residues recognized by Lon, leading to facilitated binding and subsequent cleavage by Lon protease both in vivo and in vitro.
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Transportadoras de Casetes de Unión a ATP , Adenosina Trifosfatasas/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Transporte de Monosacáridos , Proteasa La , Serina Endopeptidasas/metabolismo , Proteasas ATP-Dependientes , Proteínas Bacterianas/genética , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Caseínas/metabolismo , División Celular , Escherichia coli/citología , Proteínas de Unión a Maltosa , Mutación , Unión Proteica , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de SecuenciaRESUMEN
BACKGROUND: It remains very difficult to clarify the spatial arrangement of the branches of the pancreatic ducts in the head of the pancreas despite recent progress in diagnostic imaging techniques. METHODS: We minutely dissected the head region from 15 cadavers after injection of silicone rubber into the ducts through the papilla of Vater to investigate the distribution of these ducts. RESULTS: We found that the branches that drained the uncinate process not only joined the main pancreatic duct but also constantly joined the accessory pancreatic duct. In addition, the branches of the uncinate process that joined the accessory duct ran anterior to those to the main duct. We classified the arrangement of the pancreatic ducts into type 1 (10 cases) and type 2 (5 cases) on the basis of the pattern of the branches of the uncinate process. The distance from the papilla of Vater to the junction of the main and accessory pancreatic ducts in type 1 (> 23.0 mm) was significantly longer than that in type 2 (< 22.0 mm). CONCLUSIONS: Careful attention should be paid to the branches of the uncinate process to the accessory pancreatic duct to enable more accurate diagnoses of the pancreas head region.
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Conductos Pancreáticos/anatomía & histología , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Pancreáticas/patología , Conductos Pancreáticos/patologíaRESUMEN
Varying doses of FK506, and a cell-depleting anti-CD4 monoclonal antibody, GK1.5, were tested as either monotherapy or in combination for their effect on the survival of renal subcapsular xenografts of organ-cultured fetal pig pancreas in three strains of mice. Subcutaneous injections of FK506 at 4.0 mg/kg/day for 28 d prevented graft rejection to day 35 posttransplantation (i.e., 7 days after cessation of treatment in NOD/Lt, and CBA mice) while BALB/c mice had intact grafts at 28 days. Lower doses were less effective and immunosuppression was less effective in NOD mice than in the other strains. Even 2.0 mg/kg/day of FK506 prevented rejection in CBA mice until day 35, but not in NOD/Lt mice. GK1.5 alone did not prevent rejection in NOD/Lt mice but when a low dose of FK506 (2.0 mg/day) was added, the grafts were present, essentially intact, at 35 days. There were no obvious toxic effects of FK506 in NOD/Lt and CBA mice. With FK506 treatment there was no significant difference in absolute numbers of total leucocytes or lymphocytes in peripheral blood and spleen, but there was a decrease in thymus cellularity. Flow cytometric analysis of lymphocyte subsets in blood and spleen also showed no significant differences, but in the thymus the percentage of immature CD4/CD8 "double positive" cells increased while the more mature CD3"high", and CD4 or CD8 "single-positive" cells decreased. Thus, prolonged discordant xenograft survival in mice is possible and the use of two agents that act on different parts of the immune system allows a reduction in the dose of FK506 to safe levels.
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Anticuerpos Monoclonales/uso terapéutico , Antígenos CD4/inmunología , Trasplante de Tejido Fetal/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Islotes Pancreáticos/inmunología , Trasplante de Páncreas/inmunología , Tacrolimus/uso terapéutico , Trasplante Heterólogo/inmunología , Animales , Antígenos de Superficie/análisis , Diabetes Mellitus Tipo 1/cirugía , Femenino , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Islotes Pancreáticos/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos CBA , Ratones Endogámicos NOD , Estado Prediabético/cirugía , Especificidad de la Especie , Porcinos , Subgrupos de Linfocitos T/inmunología , Factores de TiempoRESUMEN
Microscopic fluorometry of cultured rat hippocampal neurones revealed that the intracellular concentration of Ca2+ ([Ca2+]i) rises in response to the activation of excitatory amino acid receptor (EAA-R), which included not only N-methyl-D-aspartate subspecies but also kainate and quisqualate subspecies of EAA-R. Each EAA-R mediated [Ca2+]i rise consisted of the components dependent on and independent of the activity of the voltage-dependent Ca2+ channel. The receptor-mediated voltage-independent [Ca2+]i rise may be related to the modulation of synaptic transmission efficacy.
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Calcio/metabolismo , Citoplasma/metabolismo , Hipocampo/metabolismo , Neuronas/metabolismo , Receptores de Superficie Celular/fisiología , Animales , Canales de Calcio/metabolismo , Células Cultivadas , Medios de Cultivo , Hipocampo/citología , Procesamiento de Imagen Asistido por Computador , Ácido Kaínico/farmacología , N-Metilaspartato/metabolismo , Cloruro de Potasio/farmacología , Ácido Quiscuálico/farmacología , Ratas , Receptores de Aminoácidos , Sodio/metabolismo , Espectrometría de Fluorescencia , Sinapsis/fisiología , Transmisión Sináptica/fisiologíaRESUMEN
This paper describes the binding properties of [3H]peptidergic opioid ligands to binding sites solubilized from rat brain membranes by the treatment with 0.125% sodium glycodeoxycholate and 1 M NaCl. The highest amount of the specific binding of [3H]-[D-Ala2-, Met5]enkephalinamide was obtainable when 10-fold diluted solubilized preparations were incubated in the presence of 0.1 mM MnCl2 and 100 mM NaCl at 0 degree C (on ice) for 3 h. With this assay condition, the significant binding of following [3H]opioid ligands, which have been thought to be selective for receptor types, was also observed: [3H]-[D-Ala2, MePhe4, Gly-ol5]enkephalin (mu-type), [3H]-[D-Ala2, D-Leu5]enkephalin (delta-type) and [3H]dynorphin1-9 (kappa-type). The number of binding sites in solubilized preparations for each [3H]ligand corresponded to 40-50% recovery of original membrane-bound binding sites. The Scatchard plot of the concentration-saturation binding curve showed only one class of binding sites, with a high affinity for each [3H]ligand. Apparent dissociation constants between solubilized receptors and [3H]ligands were the same as membrane-bound ones, but the ligand specificity for each receptor-type, which was examined by binding inhibition tests with unlabeled ligands, decreased. Present results indicate that heterogeneous opioid receptors in rat brain membranes seem to be transformed into less heterogeneous forms through the treatment with glycodeoxycholate and NaCl and the dilution process.
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Encéfalo/metabolismo , Receptores Opioides/metabolismo , Animales , Dinorfinas/metabolismo , Encefalina Ala(2)-MeFe(4)-Gli(5) , Encefalina Metionina/análogos & derivados , Encefalina Metionina/metabolismo , Encefalinas/metabolismo , Ácido Glicodesoxicólico , Masculino , Naloxona/metabolismo , Fragmentos de Péptidos/metabolismo , Ratas , Ratas Endogámicas , Cloruro de Sodio , SolucionesRESUMEN
The increase in intracellular Ca2+ concentration, [Ca2+]i, induced by isomers of 2-(carboxycyclopropyl)glycine (CCG) was examined in cultured rat hippocampal neurons. Some CCG isomers and N-methyl-D-aspartate (NMDA) increased [Ca2+]i in a concentration dependent manner. The 2S,3R,4S isomer of CCG (L-CCG-IV) was the most potent in elevating [Ca2+]i, and its activity was more than 100 times higher than that of NMDA and about 10 times higher than that of L-glutamate. The increase in [Ca2+]i was effectively blocked by NMDA blockers and Mg2+, and was markedly augmented by the addition of a low concentration of glycine. L-CCG-IV would be a useful tool for elucidation of functions of NMDA receptors.
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Aminoácidos Dicarboxílicos/farmacología , Calcio/metabolismo , Hipocampo/metabolismo , N-Metilaspartato/farmacología , Neuronas/metabolismo , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Aminoácidos Dicarboxílicos/antagonistas & inhibidores , Animales , Células Cultivadas , Hipocampo/citología , Neuronas/efectos de los fármacos , RatasRESUMEN
Acetylcholine (ACh) caused various patterns of change in the intracellular Ca2+ concentration ([Ca2+]i) in cultured rat hippocampal neurons. We studied the underlying mechanisms of the [Ca2+]i changes with simultaneous recording of [Ca2+]i and membrane potential/current. In most cases, [Ca2+]i rise was accompanied by a membrane depolarization. The [Ca2+]i change was significantly reduced when the membrane was voltage clamped, which implies that most of the [Ca2+]i rise results from the Ca2+ influx through the voltage-gated Ca2+ channel activated by the membrane depolarization. The membrane depolarizations were classified into two types, one associated with membrane conductance decrease and the other associated with membrane conductance increase. The former results from potassium conductance ((gK+) decrease, and the latter may result from the activation of a Na(+)-permeable channel. However, [Ca2+]i elevation was also observed in some neurons showing membrane hyperpolarization in response to ACh. This seems to show that ACh liberates Ca2+ from the intracellular Ca2+ store, resulting in the activation of a calcium-dependent K+ channel (KCa). The variations of ACh response in the hippocampal neurons seem to result from a variety of muscarinic acetylcholine receptors and various species of ion channels governed by those receptors.
Asunto(s)
Acetilcolina/farmacología , Calcio/fisiología , Hipocampo/fisiología , Animales , Calcio/metabolismo , Células Cultivadas , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Potenciales de la Membrana/efectos de los fármacos , RatasRESUMEN
Microfluorometry with fura-2 was applied to study the action of the anticonvulsant (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) on N-methyl-D-aspartate (NMDA)-induced increase in intracellular Ca2+ concentration ([Ca2+]i) in cultured mouse hippocampal neurons. MK-801 caused a potent and long-lasting blockade of the NMDA-activated [Ca2+]i elevation in a selective manner, not affecting the [Ca2+]i rise induced by quisqualate or kainate. Blockade and recovery from the blockade by MK-801 showed use dependency; the degree of blockade was dependent on the presence of NMDA. The use-dependent onset of antagonism was, however, highly sensitive to the bath temperature. MK-801 applied in the absence of NMDA had no effect on the response to subsequent application of NMDA at 22 degrees C, whereas it reduced the subsequent response to NMDA significantly at 37 degrees C. MK-801 interacted with the receptor-ion channel complex even when Mg2+, which is considered to block the open channel, had already blocked the NMDA-induced [Ca2+]i. The recovery from blockade by MK-801 was not accelerated by the application of 10 mM Mg2+ for 5 min. These results suggest that MK-801 can gain access to its binding site in the absence of NMDA at physiological temperature, and that this binding site is distinct from that for Mg2+.
Asunto(s)
Ácido Aspártico/análogos & derivados , Calcio/metabolismo , Dibenzocicloheptenos/farmacología , Hipocampo/metabolismo , Receptores de Neurotransmisores/fisiología , Animales , Ácido Aspártico/farmacología , Células Cultivadas , Maleato de Dizocilpina , Hipocampo/efectos de los fármacos , Ratones , Ratones Endogámicos ICR , N-Metilaspartato , Receptores de N-Metil-D-Aspartato , Receptores de Neurotransmisores/efectos de los fármacos , TemperaturaRESUMEN
SETTING: Transforming growth factor-beta (TGF-beta) plays an important role in many diseases, influencing as it does such processes as immune responses, fibrosing processes, and angiogenesis. Recently, polymorphisms have been described for TGF-beta that are associated with the risk of several diseases. In this study, we investigated whether TGF-beta 1 polymorphism has an effect on sarcoidosis and tuberculosis. OBJECTIVE: TGF-beta 1 Codon 10 T869C polymorphism was investigated in 110 healthy control subjects, 104 sarcoidosis patients, and 101 tuberculosis patients. DESIGN: The TGF-beta genotype was determined using polymerase chain reaction restriction fragment length polymorphism. RESULTS: We found no significant differences in TGF-beta genotypes between sarcoidosis patients and healthy controls or tuberculosis patients and controls. The long axis of the tuberculin skin test was larger in the CC type compared with the CT type. However, there was no association between the TGF-beta genotype and the roentgenographic stage, the disappearance of shadows, or organ involvement in sarcoidosis, nor any association between genotype, the extent or type of roentgenographic shadow, or detected volume of tubercle bacilli in tuberculosis. CONCLUSION: From the results, we believe that TGF-beta polymorphisms on the whole do not have a strong influence on disease onset or clinical progression in sarcoidosis and tuberculosis, although this polymorphism might have an effect on the immune response in a tuberculosis host.