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1.
Cells ; 13(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38891051

RESUMO

Respiratory viruses cause airway inflammation, resulting in epithelial injury and repair. miRNAs, including miR-149-5p, regulate different pathological conditions. We aimed to determine how miR-149-5p functions in regulating pro-inflammatory IL-6 and p63, key regulators of airway epithelial wound repair, in response to viral proteins in bronchial (BEAS-2B) and alveolar (A549) epithelial cells. BEAS-2B or A549 cells were incubated with poly (I:C, 0.5 µg/mL) for 48 h or SARS-CoV-2 spike protein-1 or 2 subunit (S1 or S2, 1 µg/mL) for 24 h. miR-149-5p was suppressed in BEAS-2B challenged with poly (I:C), correlating with IL-6 and p63 upregulation. miR-149-5p was down-regulated in A549 stimulated with poly (I:C); IL-6 expression increased, but p63 protein levels were undetectable. miR-149-5p remained unchanged in cells exposed to S1 or S2, while S1 transfection increased IL-6 expression in BEAS-2B cells. Ectopic over-expression of miR-149-5p in BEAS-2B cells suppressed IL-6 and p63 mRNA levels and inhibited poly (I:C)-induced IL-6 and p63 mRNA expressions. miR-149-5p directly suppressed IL-6 mRNA in BEAS-2B cells. Hence, BEAS-2B cells respond differently to poly (I:C), S1 or S2 compared to A549 cells. Thus, miR-149-5p dysregulation may be involved in poly (I:C)-stimulated but not S1- or S2-stimulated increased IL-6 production and p63 expression in BEAS-2B cells.


Assuntos
Células Epiteliais , Interleucina-6 , MicroRNAs , Poli I-C , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Interleucina-6/metabolismo , Células A549 , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Poli I-C/farmacologia , SARS-CoV-2 , COVID-19/metabolismo , COVID-19/virologia , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regulação da Expressão Gênica/efeitos dos fármacos
2.
Mediastinum ; 8: 5, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38322190

RESUMO

Locally invasive thymic neoplasms are challenging clinical scenarios and typically require a multidisciplinary approach. The involvement of major mediastinal veins such as the superior vena cava (SVC) used to be a contraindication to surgery, but with improved surgical technique and outcomes, this paradigm has shifted. In some situations, complex resections and reconstructions may be indicated and required to improve the long-term outcome of these patients. We report two of our cases along with a current review of literature. We also describe the preoperative workup, operative techniques, postoperative management, complications, and outcomes of patients with invasive thymic neoplasms that involve the mediastinal veins. Our first case describes a patient who was diagnosed with a thymoma extending from the diaphragm to the base of the neck that was also encasing major vascular structures including the SVC and left innominate vein. Our second case describes a patient who was also diagnosed with a large anterior mediastinal mass encasing the great veins and invading the chest wall. We describe the management of these patients and then delve deeper into operative techniques including SVC resection and reconstruction. We describe the types of conduits that can be used and complications to be mindful of when clamping the great veins, such as the SVC. Improvements in conduit materials and neoadjuvant and adjuvant therapies over the years have made it more feasible for patients with invasive thymic neoplasms to undergo surgery.

3.
Exp Physiol ; 108(3): 448-464, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36808666

RESUMO

NEW FINDINGS: What is the central question of this study? Are biomarkers of endothelial function, oxidative stress and inflammation altered by non-freezing cold injury (NFCI)? What is the main finding and its importance? Baseline plasma [interleukin-10] and [syndecan-1] were elevated in individuals with NFCI and cold-exposed control participants. Increased [endothelin-1] following thermal challenges might explain, in part, the increased pain/discomfort experienced with NFCI. Mild to moderate chronic NFCI does not appear to be associated with either oxidative stress or a pro-inflammatory state. Baseline [interleukin-10] and [syndecan-1] and post-heating [endothelin-1] are the most promising candidates for diagnosis of NFCI. ABSTRACT: Plasma biomarkers of inflammation, oxidative stress, endothelial function and damage were examined in 16 individuals with chronic NFCI (NFCI) and matched control participants with (COLD, n = 17) or without (CON, n = 14) previous cold exposure. Venous blood samples were collected at baseline to assess plasma biomarkers of endothelial function (nitrate, nitrite and endothelin-1), inflammation [interleukin-6 (IL-6), interleukin-10 (IL-10), tumour necrosis factor alpha and E-selectin], oxidative stress [protein carbonyl, 4-hydroxy-2-nonenal (4-HNE), superoxide dismutase and nitrotyrosine) and endothelial damage [von Willebrand factor, syndecan-1 and tissue type plasminogen activator (TTPA)]. Immediately after whole-body heating and separately, foot cooling, blood samples were taken for measurement of plasma [nitrate], [nitrite], [endothelin-1], [IL-6], [4-HNE] and [TTPA]. At baseline, [IL-10] and [syndecan-1] were increased in NFCI (P < 0.001 and P = 0.015, respectively) and COLD (P = 0.033 and P = 0.030, respectively) compared with CON participants. The [4-HNE] was elevated in CON compared with both NFCI (P = 0.002) and COLD (P < 0.001). [Endothelin-1] was elevated in NFCI compared with COLD (P < 0.001) post-heating. The [4-HNE] was lower in NFCI compared with CON post-heating (P = 0.032) and lower than both COLD (P = 0.02) and CON (P = 0.015) post-cooling. No between-group differences were seen for the other biomarkers. Mild to moderate chronic NFCI does not appear to be associated with a pro-inflammatory state or oxidative stress. Baseline [IL-10] and [syndecan-1] and post-heating [endothelin-1] are the most promising candidates for diagnosing NFCI, but it is likely that a combination of tests will be required.


Assuntos
Lesão por Frio , Interleucina-10 , Humanos , Ativador de Plasminogênio Tecidual , Sindecana-1 , Nitratos , Nitritos , Interleucina-6 , Endotelina-1 , Estresse Oxidativo , Inflamação , Biomarcadores , Temperatura Baixa
4.
J Surg Oncol ; 127(2): 336-342, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36630098

RESUMO

Resection and reconstruction of the chest wall can pose unique challenges given its vital role in the protection of the thoracic viscera and the dynamic part it plays in respiration. A number of new three-dimensional (3D) technologies may be invaluable in tackling these challenges. Herein we review the use of 3D technologies in preoperative imaging with virtual 3D models, printing of 3D models for preoperative planning, and printing of 3D prostheses when approaching complex chest wall reconstruction.


Assuntos
Procedimentos de Cirurgia Plástica , Parede Torácica , Humanos , Parede Torácica/diagnóstico por imagem , Parede Torácica/cirurgia , Impressão Tridimensional , Próteses e Implantes , Imageamento Tridimensional/métodos
5.
Kidney Int Rep ; 7(7): 1524-1538, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35812272

RESUMO

Introduction: Acute kidney injury (AKI) is common in hospitalized patients and associated with poor outcomes. Current methods for identifying AKI (rise in serum creatinine [sCr] or fall in urine output [UO]) are inadequate and delay detection. Early detection of AKI with easily measurable biomarkers might improve outcomes by facilitating early implementation of AKI care pathways. Methods: From a porcine model of AKI, we identified trace elements (TEs) in urine that were associated with subsequent development of AKI. We tested these putative biomarkers in 2 observational cohort studies of patients at high risk of AKI: 151 patients undergoing cardiac surgery and 150 patients admitted to a general adult intensive care unit (ICU). Results: In adults admitted to the ICU, urinary cadmium (Cd) (adjusted for urinary creatinine) had area under the receiver operating characteristic curve (AUROC) 0.70 and negative predictive value (NPV) 89%; copper (Cu) had AUROC 0.76 and NPV 91%. In humans (but not pigs), urinary zinc (Zn) was also associated with AKI and, in the ICU study, had AUROC 0.67 and NPV 80%. In patients undergoing cardiac surgery, Zn had AUROC 0.77 and NPV 91%; urinary Cd and Cu had poor AUROC but NPV of 93% and 95%, respectively. In control studies, we found that the urinary biomarkers are stable at room temperature for at least 14 days and are not affected by other confounding factors, such as chronic kidney disease (CKD). Conclusion: Urinary Cd, Cu, and Zn are novel biomarkers for early detection of AKI. Urinary trace metals have advantages over proteins as AKI biomarkers because they are stable at room temperature and have potential for cheap point-of-care testing using electrochemistry.

6.
Ann Transl Med ; 9(10): 900, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34164534

RESUMO

There is a very well-established and complex interplay between gastroesophageal reflux and lung disease. This is particularly true in end-stage lung disease and post-lung transplant patients. Numerous studies have shown that in patients who are undergoing pre-lung transplant evaluations for diseases such as idiopathic pulmonary fibrosis (IPF), emphysema, connective tissue disease, there is a high prevalence of gastroesophageal reflux and esophageal dysmotility. Post-lung transplant, many of the reflux issues persist or worsen, and there is some evidence to suggest that this leads to worsened long-term allograft function and bronchiolitis obliterans. Anti-reflux operations in patients with lung disease have been shown to be safe in both the pre and post-lung transplant setting and lead to improved reflux symptoms, as well as protecting against reflux induced allograft dysfunction in the post-lung transplant patients. Barrett's esophagus and esophageal malignancy are also not unheard of in these patients, and select patients may benefit from operative intervention. This review discusses the links between gastroesophageal reflux and lung transplant patients in both the pre and post-transplant setting. We also review the approach to the workup of esophageal disease in the pre-lung transplant setting as well as the surgical management of this unique group of patients.

7.
8.
Exp Physiol ; 105(6): 932-939, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32170890

RESUMO

NEW FINDINGS: What is the central question of this study? Are the urinary concentrations of NO and ATP, and their metabolites, associated with the severity of symptoms of overactive bladder? What is the main finding and its importance? The urinary ratios of [ATP/NO], [ADP/NO] and a combination of these, [ATP/Cr*ADP/Cr]/[NO/Cr], were correlated with overall OAB symptom severity, with the latter combination also being correlated with the severity of urinary frequency and urgency symptoms individually. Together, these data reveal changes in urothelial signalling that accompany the transition from physiology to pathology. ABSTRACT: Overactive bladder (OAB) is a highly prevalent symptom complex characterized by symptoms of urinary urgency and increased frequency and waking to void (nocturia), with or without urge incontinence and in the absence of proven infection or other obvious pathology. The underlying pathophysiology of idiopathic OAB is not clearly known, and the existence of several phenotypes has been proposed. Current diagnostic approaches are based on discordant measures, suffer from subjectivity and are incapable of detecting the proposed OAB phenotypes. Nitric oxide, ATP and their metabolites have previously been shown to underlie the perception of bladder fullness, with their release modifying the pathological perception of urgency. Therefore, in this study we assessed the concentrations of NO, ATP and associated metabolites in the urine of 113 consenting participants recruited from the general population. Recruited participants completed a questionnaire to measure the severity of OAB-associated urinary symptoms and provided a mid-stream urine sample. After identification of infection and haematuria using microbiology and microscopy, 95 samples were subjected to assays to measure NO, NO2- , NO3- , ATP, ADP and creatinine (Cr). There was no correlation between [NO/Cr], [NO2- /Cr] or [NO3- /Cr] and overall OAB symptom severity. In contrast, [ATP/NO], [ADP/NO] and a combination of these, [ATP/Cr*ADP/Cr]/[NO/Cr], were correlated with OAB symptom severity, and [ATP/Cr*ADP/Cr]/[NO/Cr] was also correlated with the severity of urinary frequency and urgency. This study adds to a growing literature that demonstrates the potential of urinary biomarkers and provides a foundation for a larger, longitudinal study.


Assuntos
Trifosfato de Adenosina/urina , Óxido Nítrico/urina , Bexiga Urinária Hiperativa/diagnóstico , Adulto , Biomarcadores/urina , Creatinina/urina , Feminino , Humanos , Masculino , Projetos Piloto , Bexiga Urinária Hiperativa/fisiopatologia
9.
Sci Rep ; 10(1): 3085, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080289

RESUMO

Overactive bladder (OAB) is a highly prevalent symptom complex characterised by symptoms of urinary urgency, increased frequency, nocturia, with or without urge incontinence; in the absence of proven infection or other obvious pathology. The underlying pathophysiology of idiopathic OAB is not clearly known and the existence of several phenotypes has been proposed. Current diagnostic approaches are based on discordant measures, suffer from subjectivity and are incapable of detecting the proposed OAB phenotypes. In this study, cluster analysis was used as an objective approach for phenotyping participants based on their OAB characteristic symptoms and led to the identification of a low OAB symptomatic score group (cluster 1) and a high OAB symptomatic score group (cluster 2). Furthermore, the ability of several potential OAB urinary biomarkers including ATP, ACh, nitrite, MCP-1 and IL-5 and participants' confounders, age and gender, in predicting the identified high OAB symptomatic score group was assessed. A combination of urinary ATP and IL-5 plus age and gender was shown to have clinically acceptable and improved diagnostic accuracy compared to urodynamically-observed detrusor overactivity. Therefore, this study provides the foundation for the development of novel non-invasive diagnostic tools for OAB phenotypes that may lead to personalised treatment.


Assuntos
Biomarcadores/urina , Bexiga Urinária Hiperativa/diagnóstico , Urologia/normas , Acetilcolina/urina , Trifosfato de Adenosina/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiocina CCL2/urina , Análise por Conglomerados , Feminino , Humanos , Interleucina-5/urina , Masculino , Pessoa de Meia-Idade , Nitritos/urina , Noctúria/fisiopatologia , Fenótipo , Reprodutibilidade dos Testes , Bexiga Urinária/fisiopatologia , Bexiga Urinária Hiperativa/urina , Incontinência Urinária de Urgência/fisiopatologia , Sistema Urinário/fisiopatologia , Urodinâmica , Adulto Jovem
10.
Neurourol Urodyn ; 39(3): 926-934, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32049380

RESUMO

AIM: To characterize purinergic signaling in overactive bladder (OAB). METHODS: Mucosal biopsies were taken by flexible cystoscopy from patients with storage symptoms referred to Urology Departments of collaborating hospitals. Immunohistochemistry (n = 12) and Western blot analysis (n = 28) were used to establish the qualitative and quantitative expression profile of P2Y6 in human mucosa. Participants from the general population provided a mid-stream urine sample. Bioluminescent assays were used to quantify adenosine triphosphate (ATP; n = 66) and adenosine diphosphate (ADP; n = 60) concentrations, which were normalized to creatinine (Cr) concentration. All participants completed a questionnaire (International Consultation on Incontinence Questionnaire - Overactive Bladder) to score urinary symptoms of OAB. RESULTS: P2Y6 immunoreactivity, more prominent in the urothelium (colocalized with the uroepithelial marker pan-cytokeratin), was more greatly expressed in OAB compared to age- and sex-matched controls (benign prostatic hyperplasia) without OAB symptoms. Mucosal P2Y6 was positively correlated only with incontinence (P = .009). Both urinary ATP and its hydrolysis product, ADP, an agonist to P2Y6, were positively correlated with total OAB symptom score (P = .010 and P = .042, respectively). CONCLUSIONS: The positive correlation of P2Y6 only with incontinence may indicate a different phenotype in OAB wet and warrants further investigation. Positive correlations of ATP and ADP with total OAB symptom score demonstrate upregulation in purinergic signaling in OAB; shown previously only in animal models. Further research is required to validate whether purinoceptors are indeed new therapeutic targets for this highly prevalent symptom complex.


Assuntos
Difosfato de Adenosina/urina , Trifosfato de Adenosina/urina , Mucosa/metabolismo , Receptores Purinérgicos P2/metabolismo , Bexiga Urinária Hiperativa/metabolismo , Bexiga Urinária/metabolismo , Incontinência Urinária/metabolismo , Urotélio/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Creatinina/urina , Cistoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Hiperplasia Prostática/fisiopatologia , Inquéritos e Questionários , Bexiga Urinária/patologia , Bexiga Urinária/fisiopatologia , Bexiga Urinária Hiperativa/patologia , Bexiga Urinária Hiperativa/fisiopatologia , Incontinência Urinária/patologia , Incontinência Urinária/fisiopatologia
12.
Cytokine ; 110: 277-283, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29402724

RESUMO

This study examined the acute and chronic effects of euhydrated and hypohydrated heat exposure, on biomarkers of stress and inflammation. Eight trained males [mean (SD) age: 21 (3) y; mass: 77.30 (4.88) kg; V̇O2max: 56.9 (7.2) mL kg-1 min-1] undertook two heat acclimation programmes (balanced cross-over design), once drinking to maintain euhydration and once with restricted fluid-intake (permissive dehydration). Days 1, 6, and 11 were 60 min euhydrated exercise-heat stress tests (40 °C; 50% RH, 35% peak power output), days 2-5 and 7-10 were 90 min, isothermal-strain (target rectal temperature: 38.5 °C) exercise-heat sessions. Plasma was obtained pre- and post- exercise on day 1, 2, and 11 and analysed for cortisol, interleukin-6 (IL-6), and C-reactive protein (CRP). Cortisol and CRP were also assessed on day 6. IL-6 was elevated following the initial (acute) 90 min isothermal heat strain exercise-heat exposure (day 2) with permissive dehydration ((pre exercise: 1.0 pg mL-1 [0.9], post-exercise: 1.8 pg mL-1 [1.0], P = .032) and when euhydrated (pre-exercise: 1.0 pg mL-1 [1.4], post-exercise: 1.6 pg mL-1 [2.1], P = .048). Plasma cortisol levels were also elevated but only during permissive dehydration (P = .032). Body mass loss was strongly correlated with Δcortisol (r = -0.688, P = .003). Although there was a trend for post-exercise cortisol to be decreased following both heat acclimation programmes (chronic effects), there were no within or between intervention differences in IL-6 or CRP. In conclusion, acute exercise in the heat increased IL-6 and cortisol only when fluid-intake is restricted. There were no chronic effects of either intervention on biomarkers of inflammation as evidenced by IL-6 and CRP returning to basal level at the end of heat acclimation.


Assuntos
Proteína C-Reativa/metabolismo , Desidratação/sangue , Desidratação/metabolismo , Exercício Físico/fisiologia , Interleucina-6/sangue , Adulto , Teste de Esforço/métodos , Temperatura Alta , Humanos , Masculino , Adulto Jovem
15.
Neurourol Urodyn ; 31(3): 317-21, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22419355

RESUMO

AIMS: To report the outcome of the think tank on prolonged bladder overdistension from the 3rd ICI-RS meeting. METHODS: Prolonged bladder overdistension was discussed after acute urinary retention, its terminology, its prevalence, pathophysiology, and consequences, as well as prophylactic and therapeutic aspects. RESULTS: Acute prolonged bladder overdistension (ApBO) is a consequence of undetected or inadequately treated acute retention, and is mostly due to regional anesthesia, prolonged childbirth, or extensive surgery. Currently, there is no agreed terminology. A primary, temporary neurogenic detrusor dysfunction causing retention is associated with decreased or absent bladder sensation therefore patients do not complain, and management is delayed. Therapeutically, the first intervention is to drain the bladder. Recovery depends on whether reversible or irreversible damage has occurred. There are no good data to support the use of drugs or sacral neuromodulation. Intravesical electrostimulation is the only treatment that has specifically addressed this problem with encouraging results. There are no recent reports on the effect of surgery for myogenic bladder damage. CONCLUSION: ApBO is an important, but often unrecognized medical complication. There is a need for defining the terminology, for studies to record the incidence of different types of bladder overdistension, and to establish management strategies. Apart from clean intermittent self catheterization (CIC) there are no data justifying pharmacological or other therapies. Therefore, prevention is of paramount importance and there is a need to develop and test preventative strategies, which should then be incorporated in surgical registries.


Assuntos
Bexiga Urinária/fisiopatologia , Retenção Urinária/complicações , Doença Aguda , Técnicas de Diagnóstico Urológico , Humanos , Valor Preditivo dos Testes , Prevalência , Prognóstico , Fatores de Risco , Terminologia como Assunto , Bexiga Urinária/inervação , Retenção Urinária/classificação , Retenção Urinária/epidemiologia , Retenção Urinária/fisiopatologia , Retenção Urinária/terapia , Urodinâmica
16.
BJU Int ; 110(8 Pt B): E397-401, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22372963

RESUMO

OBJECTIVE: To determine whether muscarinic receptor antagonism affects stretching-induced release of ATP. MATERIALS AND METHODS: Mucosal strips, dissected from guinea pig (male, 450g; n = 10) urinary bladders, were placed in horizontal organ baths and superfused with Ca(2+) -free Tyrode's solution. Superfusate samples were taken pre- and post- intervention (rapid stretching or relaxation) and ATP concentration was quantified using a luciferin-luciferase assay. The effect of muscarinic acetylcholine receptor antagonism on ATP release was assessed by addition of methoctramine (1 µM) and 4-DAMP (10 nM). RESULTS: Rapid stretching (0 to 13.3 ± 1.2 mN; no. strips = 20) increased ATP in the superfusate to a median threefold increase over basal levels. After a period of equilibration, tension in the mucosal strips relaxed until it had reached a new steady-state after 60 min and stretching was repeated. In the presence of 4-DAMP (10 nM) or methoctramine (1 µM), ATP concentrations after stretching reduced to 61% or 20%, respectively. By contrast, ATP concentrations in mucosa-matched controls, perfused with vehicle, increased in response to stretching by 391% and 1500%, respectively. Rapid relaxation also stimulated ATP release. This release did not appear to be sensitive to 4-DAMP or methoctramine. CONCLUSIONS: An alteration of resting mucosal tension is the key determinant of ATP release, as ATP is released from the mucosa in response to both stretching and relaxation. Muscarinic receptor antagonism inhibits stretching-evoked ATP release from bladder mucosa, suggesting that anticholinergic agents used to treat human lower urinary tract pathologies act on urothelial muscarinic receptors.


Assuntos
Trifosfato de Adenosina/metabolismo , Diaminas/farmacologia , Antagonistas Muscarínicos/farmacologia , Piperidinas/farmacologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologia , Urotélio/efeitos dos fármacos , Urotélio/fisiologia , Animais , Fenômenos Biomecânicos , Cobaias , Técnicas In Vitro , Masculino , Mucosa/efeitos dos fármacos , Mucosa/fisiologia
17.
Exp Physiol ; 94(7): 834-46, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19395661

RESUMO

The aim of this study was to investigate the effect of 17beta-oestradiol (E(2)) on detrusor smooth muscle contractility and its possible neuroprotective role against ischaemic-like condition, which could arise during overactive bladder disease. The effect of E(2) was investigated on rat detrusor muscle strips stimulated with carbachol, KCl and electrically, in the absence or presence of a selective oestrogen receptor antagonist (ICI 182,780) and, by using confocal Ca(2+) imaging technique, measuring the amplitude (DeltaF/F(0)) and the frequency of spontaneous whole cell Ca(2+) flashes. Moreover, the effect of 1 and 2 h of anoxia-glucopenia and reperfusion (A-G/R), in the absence or presence of the hormone, was evaluated in rat detrusor strips perfused with Krebs solution which underwent electrical field stimulation to stimulate intrinsic nerves; the amplitude and the frequency of Ca(2+) flashes were also measured. 17beta-Oestradiol exhibited antispasmogenic activity assessed on detrusor strips depolarized with 60 mm KCl at two different Ca(2+) concentrations. 17beta-Oestradiol at the highest concentration tested (30 microm) significantly decreased detrusor contractions induced by all the stimuli applied. In addition, the amplitude and the frequency of spontaneous Ca(2+) flashes were significantly decreased in the presence of E(2) (10 and 30 microm) compared with control detrusor strips. In strips subjected to A-G/R, a significant increase in the amplitude of both spontaneous and evoked flashes was observed. 17beta-Oestradiol was found to increase the recovery of detrusor strips subjected to A-G/R. The ability of E(2) to suppress contraction in control conditions may explain its ability to aid recovery following A-G/R.


Assuntos
Estradiol/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/fisiologia , Animais , Cálcio/fisiologia , Carbacol/farmacologia , Estimulação Elétrica , Estradiol/análogos & derivados , Fulvestranto , Técnicas In Vitro , Masculino , Microscopia Confocal , Músculo Liso/efeitos dos fármacos , Nifedipino/farmacologia , Cloreto de Potássio/farmacologia , Ratos , Ratos Wistar , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologia
18.
J Physiol ; 586(23): 5743-55, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18936079

RESUMO

Spontaneous purinergic neurotransmission was characterized in the mouse urinary bladder, a model for the pathological or ageing human bladder. Intracellular electrophysiological recording from smooth muscle cells of the detrusor muscle revealed spontaneous depolarizations, distinguishable from spontaneous action potentials (sAPs) by their amplitude (< 40 mV) and insensitivity to the L-type Ca(2+) channel blocker nifedipine (1 microm) (100 +/- 29%). Spontaneous depolarizations were abolished by the P2X(1) receptor antagonist NF449 (10 microm) (frequency 8.5 +/- 8.5% of controls), insensitive to the muscarinic acetylcholine receptor antagonist atropine (1 microm) (103.4 +/- 3.0%), and became more frequent in latrotoxin (LTX; 1 nm) (438 +/- 95%), suggesting that they are spontaneous excitatory junction potentials (sEJPs). Such sEJPs were correlated, in amplitude and timing, with focal Ca(2+) transients in smooth muscle cells (measured using confocal microscopy), suggesting a common origin: ATP binding to P2X(1) receptors. sAPs were abolished by NF449, insensitive to atropine (126 +/- 39%) and increased in frequency by LTX (930 +/- 450%) suggesting a neurogenic, purinergic origin, in common with sEJPs. By comparing the kinetics of sAPs and sEJPs, we demonstrated that sAPs occur when sufficient cation influx through P2X(1) receptors triggers L-type Ca(2+) channels; the first peak of the differentiated rising phase of depolarizations - attributed to the influx of cations through the P2X(1) receptor - is of larger amplitude for sAPs (2248 mV s(-1)) than sEJPs (439 mV s(-1)). Surprisingly, sAPs in the mouse urinary bladder, unlike those from other species, are triggered by stochastic ATP release from parasympathetic nerve terminals rather than being myogenic.


Assuntos
Miócitos de Músculo Liso/fisiologia , Receptores Purinérgicos/fisiologia , Transmissão Sináptica/fisiologia , Bexiga Urinária/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Atropina/farmacologia , Benzenossulfonatos/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/fisiologia , Sinalização do Cálcio/fisiologia , Feminino , Cinética , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/efeitos dos fármacos , Neurotransmissores/farmacologia , Nifedipino/farmacologia , Sistema Nervoso Parassimpático/fisiologia , Agonistas do Receptor Purinérgico P2 , Antagonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2X , Venenos de Aranha/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Bexiga Urinária/inervação
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