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1.
G Chir ; 35(11-12): 266-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25644727

RESUMO

AIM: Fat transfer is commonly used to fill loss of volume in depressed scars caused by trauma, deep burns or surgery. The aim of the study is to investigate the degree of fat graft take through evaluation of the microcirculation of grafted autologous adipose tissue using contrast-enhanced ultrasonography. PATIENTS AND METHOD: From 2010 to 2012 at the Department of Plastic and Reconstructive Surgery of the Traumatological Center in Turin, a study population was selected from patients with surgical indications for autologous fat transfer for scar correction. For each surgical procedure patients underwent a clinical and sonographic evaluation before and after intervention (at 1 month and 3 months). RESULTS: Out of a total of 28 interventions, 24 showed a good result; defined as improvement of the scar, and confirmed by the presence of vascularization in the transplanted tissue. In 4 cases, there was a lack of blood supply at the first evaluation but an initial good clinical scar correction. The absence of blood vessels was confirmed at 3 months accompanied by complete resorption of the transferred fat with a failure of good clinical outcome. CONCLUSION: Contrast-enhanced ultrasonography was able to evaluate the microvasculature of adipose tissue after fat transfer. Due to this characteristic, it allows to monitor and predict the take of adipose tissue and provide realistic and early information on the clinical outcome of fat transfer.


Assuntos
Tecido Adiposo/transplante , Cicatriz/diagnóstico por imagem , Adulto , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia/métodos , Adulto Jovem
2.
Radiol Med ; 116(4): 634-43, 2011 Jun.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-21424316

RESUMO

PURPOSE: The aim of this study was to evaluate whether there exists a characteristic distribution pattern of vessels within neurinomas that may be used to characterise this type of lesion by employing a contrast-specific ultrasound technique. MATERIALS AND METHODS: Between January 2003 and May 2010, 66 suspected neurinomas were evaluated according to their sonographic features (solid fusiform mass with well-defined margins located in direct continuity with the nerve that was not always discernible and heterogeneous as a result of the presence of small cystic areas or calcifications). The lesions were examined using a sonographic contrast medium consisting of sulphur hexafluoride microbubbles and equipment with dedicated contrast-specific software [contrast tuned imaging (CnTI)]. Of these lesions, five were excluded from the analysis because the definitive diagnosis was not available (in two cases, the follow-up was still in progress, whereas in the remaining three, there was no follow-up). Our study, therefore, is based on 61 surgically excised lesions that were confirmed to be neurinomas by histology, which is regarded as the gold standard. RESULTS: In 41/61 cases (67.2%), we identified an enhancement pattern that we termed reticular owing to the interweaving of blood vessels, of which two subtypes were identified depending on whether the interwoven vessels were densely or sparsely packed: loose-knit reticular in 18/41, and tight-knit reticular in 23/41. In 20/61 (32.8%) cases, we observed a vascular pattern of diffuse heterogeneous enhancement, which was divided into two subtypes based on the presence of one (7/20) or more (13/20) avascular areas. CONCLUSIONS: Results showed that all neurinomas studied could be divided into two groups according to the type of enhancement pattern observed: reticular or diffuse heterogeneous.


Assuntos
Meios de Contraste , Neurilemoma/diagnóstico por imagem , Neoplasias do Sistema Nervoso Periférico/diagnóstico por imagem , Fosfolipídeos , Hexafluoreto de Enxofre , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurilemoma/irrigação sanguínea , Neoplasias do Sistema Nervoso Periférico/irrigação sanguínea , Ultrassonografia , Adulto Jovem
3.
Eur J Radiol ; 27 Suppl 1: S60-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9652503

RESUMO

INTRODUCTION: The so-called knee impingement syndromes are very frequently reported in both professional and amateur sportsmen. PURPOSE: The objective of our study was to classify the most frequent knee changes responsible for such syndromes considering both pathology and diagnostic work-up. MATERIAL AND METHODS: Our patients complained of aspecific symptoms related to articular meniscal, ligament or cartilage, conditions. The site of pain was periarticular and there was no apparent sign of acute traumatic events. All individuals, aged 16-55, practised sports at different levels and women were the majority of the sample. The study was carried out from 1995 to 1997 and all the medical records presented in occasion of the sports-medicine check-up were reviewed. RESULTS: The sites of symptom onset were divided into medial, lateral, anterior and posterior. For each of them the most frequent conditions which could be defined as impingement syndromes, were defined paying particular attention to the possible methods of diagnosis useful to classify the disorder. As for anterior syndromes, patellofemoral disorders were the most frequent findings. They were associated with either incorrect torsion movements of the lower limbs or local dysplasia. Alterations in the single skeletal and cartilage structures were reported. Always referring to anterior syndromes, Hoffa's fat pad imflammation and the jumper's knee were a less frequent finding. As for posterior impingement syndromes, the most frequent abnormalities involved the insertional tract of the midcalf muscle associated with bursa reaction and insertional popliteus hypertrophy. As for medial syndromes, the most frequent abnormality involved the parapatellar synovial fold whose symptoms can be often mistaken for a meniscal injury. Less frequent is the involvement of the 'pes anserinus' tendinitis and the insertional enthesopathy of the semimembranosus muscle. As for lateral syndromes, the phlogistic involvement of the distal insertional tract of the broad fascia tensor tendon with bursa reaction is very frequently reported, while the inflammation of the popliteal tendon and of the femoral bicipital tendon is less common. CONCLUSIONS: Although less frequent than meniscal and ligament injuries, impingement syndromes must be taken into due consideration when looking for knee disorders resorting to different diagnosis methods. Diagnostic imaging is very useful in this regard as it allows a proper and correct diagnosis procedure for any single condition.


Assuntos
Traumatismos em Atletas/diagnóstico , Transtornos Traumáticos Cumulativos/diagnóstico , Diagnóstico por Imagem , Traumatismos do Joelho/diagnóstico , Adolescente , Adulto , Traumatismos em Atletas/etiologia , Transtornos Traumáticos Cumulativos/etiologia , Diagnóstico Diferencial , Feminino , Humanos , Traumatismos do Joelho/etiologia , Articulação do Joelho/patologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
4.
J Radiol ; 60(6-7): 429-32, 1979.
Artigo em Francês | MEDLINE | ID: mdl-501702

RESUMO

A brief report of two cases of Goodpasture's pneumonephrotoxic syndrome offers the greatest contribution that can be given by renal radiographic signs obtained by contrast radiography. Their association with already known pulmonary signs helps diagnosis and is an absolute indication for nephrobiopsy.


Assuntos
Doença Antimembrana Basal Glomerular/diagnóstico por imagem , Adulto , Humanos , Masculino , Radiografia
5.
Chir Organi Mov ; 88(2): 233-40, 2003.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-14735834

RESUMO

PURPOSE: Evaluation of bone remanagement after treatment by thermoablation of osteoid osteoma (OO) by CT scan. MATERIAL AND METHOD: Nine cases of OO (8 in the limbs, 1 in the pelvis) following biopsy were treated by CT-guided thermoablation. Clinical results, complications, density of tissues treated by CT scan (pre-postop, 6, 12 months) are evaluated. RESULTS: Absence of complications, regression of pain over 2 weeks, resumption of sports activity in 1 month. Bone density after treatment increases but even after 1 year it is much lower than normal levels. CONCLUSIONS: Bone remodeling after thermoablation of OO requires much time, the process is still visible 12 months later by CT scan. CT scan is an adequate method, not only for diagnosis and treatment, but also for follow-up, capable of evaluating in time the changes in density of the site of the lesion, which is useful for a comparison in case of postoperative pain of doubtful origin.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Ablação por Cateter , Osteoma Osteoide/diagnóstico por imagem , Osteoma Osteoide/cirurgia , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Feminino , Humanos , Masculino , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios
6.
Chir Organi Mov ; 88(2): 217-23, 2003.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-14735832

RESUMO

Soft tissue tumors, involving the vascular bundle, require a particular surgical approach: oncological and vascular surgical techniques must be integrated in order to perform a limb-saving surgery with adequate margins. Thirty-six soft tissue sarcomas of the thigh and popliteal region were treated from June 1999 to September 2002. Nineteen cases involving the vascular bundle were analysed and placed in two groups according to imaging and clinical information: Group A, 14 patients, with tumors close to femoral vessels without adventitial infiltration, and Group B, 5 patients, with vascular infiltration. Group A was treated with vascular blunt dissection performing adventitial excision. Group B was treated with vascular "en-bloc" resection and reconstruction. Imaging and clinical information together with surgical techniques, strategies and complications were analysed in order to plan the surgical approach in neoplastic vascular bundle involvement.


Assuntos
Braço , Perna (Membro) , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Masculino , Sarcoma/irrigação sanguínea , Neoplasias de Tecidos Moles/irrigação sanguínea
7.
Chir Organi Mov ; 88(2): 225-31, 2003.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-14735833

RESUMO

PURPOSE: Echocolor Power Doppler with contrast medium forms a non-invasive vascular image; the purpose of the study is to evaluate the effectiveness in differentiating benign and malignant tumors in the soft tissues of the limbs. MATERIAL AND METHOD: Echocolor Power Doppler with contrast medium was used to study 80 patients with swelling in the soft tissues of the limbs: there were 54 benign lesions, 22 sarcomas, and 4 aggressive desmoid fibromatoses. RESULTS: Were identified 4 patterns of wash-in and wash-out curves that could be correlated to the histological diagnosis: type I was present in 85% of benign lesions, type III in 91% of malignant lesions and in 3.7% of the benign ones, type II in aggressive fibromatoses, anomalous type in 4 benign lesions and 2 sarcomas; the curve was absent in 2 benign lesions. CONCLUSIONS: Power Doppler Echocolor with contrast medium can become a useful method to be associated with traditional imaging methods in the differential diagnosis of swelling of the soft tissues of the limbs.


Assuntos
Braço , Meios de Contraste , Perna (Membro) , Neoplasias de Tecidos Moles/irrigação sanguínea , Neoplasias de Tecidos Moles/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Adolescente , Adulto , Idoso , Criança , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade
10.
Rays ; 14(4): 413-7, 445-7, 1989.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-2700030
11.
Radiol Med ; 112(4): 550-61, 2007 Jun.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-17563849

RESUMO

PURPOSE: Our study aimed to assess the role of magnetic resonance imaging (MRI) in the characterisation of musculoskeletal tumours and to identify specific perfusion patterns for the different tumours. MATERIALS AND METHODS: Between January 2003 and September 2005, we evaluated the conventional and perfusion MRIs of 39 patients with musculoskeletal tumours. Dynamic MRI was performed with a 1.5-T and 1.0-T MRI unit before and after the intravenous administration of contrast material, using dedicated phased-array coils appropriate for the region to be studied and fast and ultrafast consecutive sequences. Postprocessing was done on an independent workstation (Advantage Windows, GE Medical System), with Functool (GE) software, which allowed a quantitative evaluation of enhancement as a function of time. The results were compared with the histopathological diagnoses obtained by biopsy or surgery. RESULTS: The lesions identified in the 39 patients included 23 soft tissue tumours (12 benign, 11 malignant) and 16 bone tumours (ten benign, six malignant). Comparing the time-intensity diagrams of lesions of the same histological type, we found typical enhancement patterns for some bone tumours only, especially for bone, cartilaginous, fibrohistiocytic and pseudoinflammatory lesions. No typical enhancement pattern could be detected for any of the histological types of soft tissue tumour. Analysis of the slope of the time-intensity curves has a sensitivity and specificity of 64%-58% for soft tissue tumours and 86%-67% for bone tumours in determining the biological aggressiveness of the lesions. CONCLUSIONS: Perfusion MRI had moderate sensitivity and specificity in the differential diagnosis between lesions with high or low biological activity. Only in a few cases was it possible to find some correlation between perfusion patterns and lesion histology. The slope values should therefore be used in combination with conventional spin-echo images and other imaging and clinical data in order to narrow the field of the possible differential diagnoses and reliably predict the nature of the lesion.


Assuntos
Neoplasias Ósseas/diagnóstico , Angiografia por Ressonância Magnética , Neoplasias Musculares/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Radiol Med ; 111(6): 836-45, 2006 Sep.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-16896557

RESUMO

PURPOSE: The objective of this study was to evaluate the role of magnetic resonance imaging (MRI) and ultrasonography (US) in the diagnosis of traumatic muscle injuries. MATERIALS AND METHODS: From June 2003 to June 2004, 81 football players with a history of traumatic muscle injuries to the lower limbs were examined. US was performed shortly after the trauma (from 6 to 72 h afterwards) and MRI within a maximum of 5 days. RESULTS: MRI revealed 26 minor and 55 major traumas. MRI and US showed complete concordance in 71 patients (site, type and extent of injury). US produced ten false negative results, including six minor lesions and four major lesions. US had a sensitivity of 87.65% in the correct identification of muscle injuries; its sensitivity was 92.72% for major lesions and 76.92% for minor lesions, 57% for delayed-onset muscle soreness (DOMS), 80% for lengthenings, 83% for contractures, 84% for strains, 87.5% for mild contusions and 100% for severe contusions. CONCLUSIONS: US is the first-line technique for examination of muscle injuries. MRI is able to reveal lesions that may be missed at US and provide a more accurate assessment of site and extent of injury.


Assuntos
Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Futebol/lesões , Adolescente , Adulto , Humanos , Músculo Esquelético/lesões , Sensibilidade e Especificidade , Ultrassonografia
13.
J Foot Ankle Surg ; 36(3): 170-2, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9232495

RESUMO

Fascial entrapment of the superficial peroneal nerve produced severe pain in the ankle and foot of a 16-year-old female athlete after several sprains of the same ankle. The pain coexisted with erythema and sensory alteration of the area involved. Magnetic resonance imaging confirmed the diagnosis of this unusual neuropathy. Limited fasciectomy, at the point where the nerve becomes subcutaneous, relieved all symptoms.


Assuntos
Síndromes de Compressão Nervosa/diagnóstico , Nervo Fibular , Adolescente , Traumatismos do Tornozelo/complicações , Fasciotomia , Feminino , Humanos , Imageamento por Ressonância Magnética , Síndromes de Compressão Nervosa/etiologia , Síndromes de Compressão Nervosa/cirurgia , Entorses e Distensões/complicações
14.
Arch Sci Med (Torino) ; 136(2): 309-18, 1979.
Artigo em Italiano | MEDLINE | ID: mdl-160218

RESUMO

Radiology has an important part to play in Goodpasture's syndrome. The radio-sympatomatological value of lung changes are clarified and subdivided into primary, secondary and mixed, and mention made of the possible significance of cardiomegaly, where present. Special attention is paid to the importance of radiological exploration of the kidneys for the recognition of changes whose concomitance with lung changes may suggest diagnosis of Goodpasture's syndrome.


Assuntos
Doença Antimembrana Basal Glomerular/diagnóstico por imagem , Adulto , Doença Antimembrana Basal Glomerular/complicações , Doença Antimembrana Basal Glomerular/patologia , Biópsia , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/etiologia , Cardiomegalia/patologia , Glomerulonefrite/diagnóstico por imagem , Glomerulonefrite/etiologia , Glomerulonefrite/patologia , Humanos , Pulmão/diagnóstico por imagem , Masculino , Urografia
15.
Radiol Med ; 99(6): 415-9, 2000 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-11262816

RESUMO

PURPOSE: The ankle impingement syndrome depends on many factors (fiber or bone production changes) manifested with pain and limited range of movement of the tibiotarsal joint. We tried to classify the various causes and sites of impingement syndromes with MRI. MATERIALS AND METHODS: A cohort of 42 selected patients underwent a 2-year orthopedic follow-up. All patients were examined with MRI using both a low field permanent dedicated magnet at 0.2 Tesla (Artoscan, Esaote Biomedica, Genoa, Italy) and a high field General Electric unit at 1.0 T; sequences and views were chosen according to the condition studied. Gd-DTPA was administered in 26/42 patients. All patients underwent arthroscopy. RESULTS: Twenty-one patients had positive symptoms in the anterolateral region of the ankle and 14 of them had lateral changes. In 13 patients we found fibrous tissue (meniscoid lesion) or hypertrophy of the synovial tissue. An intra-articular body was observed in one patient. An osteophyte was found in 5 patients at the level of the anterior margin of the tibia, with the presence of reactive synovial tissue. Three of 18 patients with posterior pain had a traumatic injury of the posterior exterior tubercle of the astragalus, 7 had a fracture of the os trigonum and 2 had small sclerotic foci formations in calceneal site; chondropathy with sclerosis of subchondral bone was diagnosed in 2 patients. Posterior bone impingement was observed in the remaining 4 patients. Two patients had synovial impingement in posterolateral site. A posterior plica synovialis was seen in 1 patient. Fibrotic-scar tissue was observed in one case, in the subtalus region (impingement synovialis subtalaris). The administration of intra-articular Gd-DTPA provided better definition of the fibrous tissue and the intra-articular free bodies. Modest vascular enhancement of the tissues was seen in 9 of 8 patients receiving the contrast agent. In the other two cases, where signal tissue was low, no signal enhancement was observed after the contrast agent administration. DISCUSSION: Based on integrated MR, clinical and arthroscopic findings we classified tibiotarsal joint impingement syndromes into three types, namely: 1) bone impingement; 2) fibrous impingement where both site and grade are considered; 3) impingement synovialis subtalaris. CONCLUSIONS: MRI appears to be a fundamental diagnostic imaging tool in depicting and detailing the various patterns and sites of the impingement syndrome of the tibiotarsal joint thus allowing an objective classification.


Assuntos
Articulação do Tornozelo/patologia , Imageamento por Ressonância Magnética , Adulto , Feminino , Humanos , Artropatias/patologia , Masculino , Síndrome
16.
Radiol Med ; 75(3): 151-5, 1988 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-3357985

RESUMO

One hundred and ninety-three shoulder arthrographies were performed between 1979 and 1985 on patients affected by recurrent dislocations. The diagnostic doubt was cleared up in 162 cases (83%). Arthrographic diagnosis was confirmed by pathological findings in 92% of the patients who underwent surgery. The double-contrast technique under local anaesthesia with anterior access is suggested, since it allows several arthrograms in different projections. Thus, an analytic study of the articular damage can be carried out. The patterns of each projection are briefly shown. Revision of case histories points out that: a) the use of arthrography should always be assessed on a clinical-radiological basis for each patient; b) there is no doubt as to the usefulness of this examination as a direct means of exploration, as far as the articular damage is concerned, not only as an aid to future surgery, but also in the follow-up of the results of the treatment in the long run.


Assuntos
Artrografia/métodos , Meios de Contraste/administração & dosagem , Luxação do Ombro/diagnóstico por imagem , Humanos , Injeções Intra-Articulares , Recidiva
17.
Radiol Med ; 104(1-2): 68-74, 2002.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-12386557

RESUMO

PURPOSE: To propose a graded classification of lesions of the fibrocartilaginous glenoid labrum in traumatic dislocations of the shoulder, based on arthro-MRI in sagittal-oblique views. MATERIALS AND METHODS: Seventy-one patients with histories of chronic post-traumatic shoulder instability were studied from May 2000 to May 2001. MR images were obtained using superconducting magnets operating at 1 and 1.5 Tesla, with a dedicated shoulder coil. The study was carried out in combination with arthrography, with axial sections oriented perpendicularly to the longitudinal axis of the glena, oblique coronal sections parallel to the course of the supraspinous muscle tendon and oblique sagittal sections with axis parallel to the longitudinal axis of the glena. RESULTS: In one case an anatomical variant was found (Buford complex). In 18 patients a simple fissuration of the fibrocartilaginous glenoid labrum was found, whereas 28 patients displayed more extensive lesions affecting the middle-inferior portions of the labrum. In 15 patients the lesion extended to the middle-superior third of the glena, involving the middle glenohumeral ligament. In 9 cases, in addition to a complete lesion of the labrum, with typical "bucket-handle" appearance, a lesion of the superior and middle glenohumeral ligaments was also observed. DISCUSSION AND CONCLUSIONS: In traumatic shoulder dislocations it is essential to provide the surgeon with precise information regarding the location, extension and degree of damage to the capsule, ligaments and especially the labrum of the glenohumeral joint. On the basis of the results obtained in the sagittal-oblique sections we propose an MR-arthrography classification dividing lesions of the fibrocartilaginous labrum into 4 grades.


Assuntos
Artrografia , Instabilidade Articular/diagnóstico , Imageamento por Ressonância Magnética , Escápula , Luxação do Ombro/diagnóstico , Adolescente , Adulto , Artrografia/métodos , Doença Crônica , Feminino , Humanos , Aumento da Imagem , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Luxação do Ombro/complicações , Luxação do Ombro/diagnóstico por imagem , Luxação do Ombro/etiologia
18.
Radiol Med ; 89(3): 211-4, 1995 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-7754109

RESUMO

In the study of osteoarticular conditions, MRI makes a definite diagnostic improvement, even though some problems are still to be solved. Thus, on the basis of their arthrographic experience, the authors experimentally applied this technique to MRI, to assess the actual feasibility of MR arthrography. Forty-three patients were selected to undergo MR examinations after the intraarticular injection of 15-20 ml paramagnetic contrast agent (Gd-DTPA), with 0.25% saline solution. Before MR arthrography every patient underwent a baseline MR arthrography exam. Normal anatomy was better depicted with MR arthrography. In all cases, even small lesions and other structural changes missed at baseline MRI were demonstrated. Therefore, in agreement with previous arthrographic and CT arthrographic reports, we believe MR arthrography to be a simple technique improving MR diagnostic capabilities in selected cases.


Assuntos
Artrografia , Imageamento por Ressonância Magnética , Articulação do Tornozelo/patologia , Meios de Contraste , Estudos de Avaliação como Assunto , Gadolínio , Gadolínio DTPA , Humanos , Instabilidade Articular/diagnóstico , Traumatismos do Joelho/diagnóstico , Articulação do Joelho/patologia , Compostos Organometálicos , Ácido Pentético/análogos & derivados , Manguito Rotador/patologia , Lesões do Manguito Rotador , Articulação do Ombro/patologia
19.
Am J Physiol Cell Physiol ; 281(2): C624-32, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11443062

RESUMO

A6 model renal epithelial cells were stably transfected with enhanced green fluorescent protein (EGFP)-tagged alpha- or beta-subunits of the epithelial Na(+) channel (ENaC). Transfected RNA and proteins were both expressed in low abundance, similar to the endogenous levels of ENaC in native cells. In living cells, laser scanning confocal microscopy revealed a predominantly subapical distribution of EGFP-labeled subunits, suggesting a readily accessible pool of subunits available to participate in Na(+) transport. The basal level of Na(+) transport in the clonal lines was enhanced two- to fourfold relative to the parent line. Natriferic responses to insulin or aldosterone were similar in magnitude to the parent line, while forskolin-stimulated Na(+) transport was 64% greater than control in both the alpha- and beta-transfected lines. In response to forskolin, EGFP-labeled channel subunits traffic to the apical membrane. These data suggest that channel regulators, not the channel per se, form the rate-limiting step in response to insulin or aldosterone stimulation, while the number of channel subunits is important for basal as well as cAMP-stimulated Na(+) transport.


Assuntos
Células Epiteliais/metabolismo , Canais de Sódio/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Membrana Celular/metabolismo , Células Clonais , Colforsina/farmacologia , Células Epiteliais/ultraestrutura , Canais Epiteliais de Sódio , Proteínas de Fluorescência Verde , Indicadores e Reagentes , Proteínas Luminescentes , Microscopia Confocal , Isoformas de Proteínas/metabolismo , Distribuição Tecidual , Xenopus
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