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1.
J Cell Physiol ; 226(12): 3156-68, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21321934

RESUMO

Peripheral blood-derived multipotent adult progenitor cells (PBD-MAPCs) are a novel population of stem cells, isolated from venous blood of green fluorescent protein transgenic swine, which proliferate as multicellular non-adherent spheroids. Using a simple differentiation protocol, a large proportion of these cells developed one of five distinct neural cell phenotypes, indicating that these primordial cells have high neurogenic potential. Cells exhibiting neural morphologies developed within 48 h of exposure to differentiation conditions, increased in percentage over 2 weeks, and stably maintained the neural phenotype for three additional weeks in the absence of neurogenic signaling molecules. Cells exhibited dynamic neural-like behaviors including extension and retraction of processes with growth cone-like structures rich in filamentous actin, cell migration following a leading process, and various cell-cell interactions. Differentiated cells expressed neural markers, NeuN, ß-tubulin III and synaptic proteins, and progenitor cells expressed the stem cell markers nestin and NANOG. Neurally differentiated PBD-MAPCs exhibited voltage-dependent inward and outward currents and expressed voltage-gated sodium and potassium channels, suggestive of neural-like membrane properties. PBD-MAPCs expressed early neural markers and developed neural phenotypes when provided with an extracellular matrix of laminin without the addition of cytokines or growth factors, suggesting that these multipotent cells may be primed for neural differentiation. PBD-MAPCs provide a model for understanding the mechanisms of neural differentiation from non-neural sources of adult stem cells. A similar population of cells, from humans or xenogeneic sources, may offer the potential of an accessible, renewable and non-tumorigenic source of stem cells for treating neural disorders.


Assuntos
Células-Tronco Adultas/metabolismo , Células-Tronco Multipotentes/metabolismo , Neurogênese , Neurônios/metabolismo , Animais , Animais Geneticamente Modificados , Biomarcadores/metabolismo , Movimento Celular , Forma Celular , Células Cultivadas , Matriz Extracelular/metabolismo , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Potenciais da Membrana , Proteínas do Tecido Nervoso/metabolismo , Fenótipo , Suínos , Fatores de Tempo
2.
Eur J Appl Physiol ; 110(5): 1019-27, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20680328

RESUMO

Increased endothelium-dependent vasodilatation is associated with endurance exercise training. The purpose of this study was to test the hypothesis that increased endothelial nitric oxide synthase (eNOS) protein function, but not increased vascular smooth muscle sensitivity to NO, underlies augmented endothelium-dependent dilatation with training. To test these hypotheses, rats ran on a treadmill at 30 m/min (10% grade) for 60 min/day, 5 days/week, over 8-12 weeks (Trn). Training efficacy was demonstrated by greater (P < 0.05) hindlimb muscle citrate synthase activity and left ventricular mass-body mass ratio in Trn compared with sedentary control rats (Sed). Expression of eNOS protein in the aorta was increased with training (Sed, 1.00 ± 0.18 normalized units; Trn, 1.55 ± 0.23; P < 0.05). Aortic NOS activity was, however, unchanged by training (Sed, 1,505 ± 288 fmol/h/mg protein; Trn, 1,650 ± 247; n.s.). Expression of heat shock protein 90 and protein kinase B/Akt was not different between groups, nor was their association with eNOS. In follow-up series of rats, phosphorylated eNOS content (Serine 1177) was similar for Sed and Trn in both the aorta and gastrocnemius feed artery. Aortic NOS activity with eNOS phosphorylation status preserved was also similar between groups. Finally, cGMP concentration with a NO donor did not differ between groups (Sed, 73.0 ± 20.2 pmol/mg protein; Trn, 62.5 ± 12.9; n.s.). These findings indicate that training-induced increases in eNOS protein expression are not coupled to augmented function, illustrating the complexity of eNOS regulation. Further, they show that vascular sensitivity to NO is not altered by exercise training.


Assuntos
Condicionamento Físico Animal/fisiologia , Vasodilatação/fisiologia , Animais , Aorta/enzimologia , Aorta/fisiologia , Citrato (si)-Sintase/análise , Citrato (si)-Sintase/fisiologia , GMP Cíclico/análise , Proteínas de Choque Térmico HSP90/análise , Masculino , Músculo Esquelético/enzimologia , Músculo Esquelético/fisiologia , Óxido Nítrico/análise , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase Tipo III/análise , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/análise , Ratos , Ratos Sprague-Dawley
3.
J Appl Physiol (1985) ; 105(6): 1761-71, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18832757

RESUMO

Coronary arterioles from hypercholesterolemic swine display attenuated adenosine-mediated vasodilatation that is attributable to the elimination of voltage-dependent K(+) (Kv) channel stimulation. For the present study, we tested the hypotheses that exercise training would correct impaired adenosine-induced dilatation in coronary arterioles from hypercholesterolemic pigs through restoration of adenosine activation of Kv channels and that vasodilatation to the receptor-independent adenylyl cyclase activator, forskolin, would also be attenuated in arterioles from hypercholesterolemic pigs. Pigs were randomly assigned to a control (NC) or high-fat, high-cholesterol (HC) diet for 20 wk. Four weeks after the diet was initiated, pigs from both groups were assigned to exercise training (Ex; 5 days/wk for 16 wk) or sedentary (Sed) protocols, resulting in four groups of pigs: NC-Sed, NC-Ex, HC-Sed, and HC-Ex. Arterioles ( approximately 150 mum) from both HC-Sed and HC-Ex pigs displayed impaired adenosine-mediated dilatation that was attributable to the elimination of 4-aminopyridine (4-AP; 1 mM)-sensitive Kv channel activation compared with NC counterparts. Arteriolar smooth muscle whole cell Kv currents were significantly reduced in HC-Sed compared with NC-Sed, although HC-Ex and NC-Ex did not differ. Forskolin-mediated dilatation was attenuated by 4-AP (1 mM) and in a concentration-dependent manner by tetraethylammonium (TEA; 0.1-1 mM) in NC-Sed but not HC-Sed. Further, TEA-sensitive Kv currents were diminished in cells of HC-Sed compared with NC-Sed pigs. Quantitative RT-PCR revealed similar expression levels of Kv3.1 and 3.3 in arterioles of NC-Sed and HC-Sed swine with undetectable expression of Kv1.1, 3.2, and 3.4. Taken together, these results suggest that hypercholesterolemia-mediated attenuation of adenosine-induced vasodilatation in coronary arterioles is not corrected by exercise training and is likely attributable to an impairment in the pathway coupling adenylyl cyclase with a highly TEA-sensitive Kv channel isoform(s).


Assuntos
Adenosina/farmacologia , Vasos Coronários/metabolismo , Hipercolesterolemia/metabolismo , Condicionamento Físico Animal/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/efeitos dos fármacos , 4-Aminopiridina/farmacologia , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/metabolismo , Arteríolas/fisiologia , Colesterol na Dieta/farmacologia , Colforsina/farmacologia , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Porco Miniatura , Tetraetilamônio/farmacologia , Vasodilatação/efeitos dos fármacos
4.
Endocrinology ; 148(8): 3758-64, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17510233

RESUMO

Inflammation contributes to disease development, and the neuroimmunoendocrine interface is a potential site of action for inflammatory products like IL-6 to affect health. Although plasma IL-6 can stimulate the activity of the hypothalamo-pituitary-adrenocortical (HPA) axis, the precise role, if any, for IL-6 in the HPA response to nonimmunological stressors is unclear. The purpose of this study was to test the hypothesis that IL-6 in the stalk median eminence (SME) can be directly involved in stimulating ACTH secretion in response to acute stress in female swine. This study was undertaken as a result of finding IL-6 localized to the external zone of the SME next to the hypophyseal portal vessels. Results indicate that content of IL-6 in the SME decreases in response to acute stress along with an increase in nuclear phosphorylated signal transducer and activator of transcription-3 (pSTAT-3) in pituitary corticotrophs and a simultaneous increase in plasma concentrations of IL-6 and ACTH. Furthermore, we show that females concomitantly display greater SME content of IL-6 and greater HPA responsiveness to stress, thereby suggesting that IL-6 release from the SME is an integral factor contributing to enhanced stress responsiveness in females. Our results provide evidence for a direct link between IL-6 and ACTH release and reveal a sex difference in this relationship.


Assuntos
Interleucina-6/metabolismo , Eminência Mediana/metabolismo , Caracteres Sexuais , Estresse Fisiológico/metabolismo , Estresse Fisiológico/fisiopatologia , Doença Aguda , Hormônio Adrenocorticotrópico/metabolismo , Animais , Feminino , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Esforço Físico , Sistema Hipófise-Suprarrenal/fisiologia , Restrição Física , Suínos , Porco Miniatura
5.
Stem Cells Dev ; 15(4): 507-22, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16978055

RESUMO

Multipotent self-renewing stem cell lines have been established using peripheral blood mononuclear cells from adult green fluorescent protein transgenic swine. These cells proliferate as nonadherent spheroids in primordial-specific culture media and readily differentiate into angiogenic, osteogenic, adipogenic, and neurogenic phenotypes when cultured under the appropriate conditions. These cells are designated peripheral blood-derived multipotent adult progenitor cells (PBD-MAPCs). When differentiated in endothelial-specific media, these cells exhibit a cobblestone morphology and express von Willebrand factor (vWF), take up 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarboxyanine-labeled acetylated low-density lipoprotein DiI-Ac-LDL, and form tubes with lumens when grown on pads of Matrigel. Under different culture conditions, the cells appear whorl-like in appearance and express alpha-actin, indicative of smooth muscle phenotype. In the presence of dexamethasone and ascorbic acid, PBD-MAPCs differentiate into cells that produce Alizarin Red-staining extracellular mineral, consistent with an osteogenic potential. Under different conditions the cells produce Oil Red O-staining lipid vacuoles, suggestive of an adipocyte phenotype. We have also developed conditions that induce PBDMAPCs to differentiate into neural cells, confirmed by the expression of specific neuron- and glial-specific markers. Upon transplantation into rat brain, the neurogenic cells survive and migrate throughout the striatum and corpus callosum. The cells remain brightly fluorescent throughout their time in culture, during in vitro differentiation, and after in vivo transplantation. PBD-MAPCs have been maintained in primordial cell media for more than 100 doublings, yet can be induced to differentiate rapidly and efficiently into distinct cell types. PBD-MAPCs are ideal tools to study the mechanisms of differentiation and may be superior to embryonic stem cells as cellular therapeutics.


Assuntos
Proteínas de Fluorescência Verde/genética , Células-Tronco Multipotentes/citologia , Suínos/sangue , Suínos/genética , Actinas/metabolismo , Envelhecimento , Animais , Animais Geneticamente Modificados , Encéfalo/citologia , Diferenciação Celular , Linhagem Celular , Separação Celular , Feminino , Mesoderma/citologia , Neovascularização Fisiológica/fisiologia , Neurônios/citologia , Ratos , Transplante de Células-Tronco
6.
Stem Cells Dev ; 25(15): 1109-18, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27295980

RESUMO

Individuals with neurodegenerative disorders or brain injury have few treatment options and it has been proposed that endogenous adult neural stem cells can be harnessed to repopulate dysfunctional nonneurogenic regions of the brain. We have accomplished this through the development of rationally designed hydrogel implants that recruit endogenous cells from the adult subventricular zone to create new relatively long tracts of neuroblasts. These implants are biocompatible and biodegradable cylindrical hydrogels consisting of fibrin and immobilized neurotrophic factors. When implanted into rat brain such that the cylinder intersected the migratory path of endogenous neural progenitors (the rostral migratory stream) and led into the nonneurogenic striatum, we observed a robust neurogenic response in the form of migrating neuroblasts with long (>100 µm) complex neurites. The location of these new neural cells in the striatum was directly coincident with the original track of the fibrin implant, which itself had completely degraded, and covered a significant area and distance (>2.5 mm). We also observed a significant number of neuroblasts in the striatal region between the implant track and the lateral ventricle. When these fibrin cylinders were implanted into hemiparkinson rats, correction of parkinsonian behavior was observed. There were no obvious behavioral, inflammatory or tumorigenic sequelae as a consequence of the implants. In conclusion, we have successfully engineered neural tissue in vivo, using neurogenic biomaterials cast into a unique cylindrical architecture. These results represent a novel approach to efficiently induce neurogenesis in a controlled and targeted manner, which may lead toward a new therapeutic modality for neurological disorders.


Assuntos
Envelhecimento/fisiologia , Materiais Biocompatíveis/farmacologia , Encéfalo/fisiologia , Hidrogéis/farmacologia , Mamíferos/fisiologia , Neurogênese/efeitos dos fármacos , Engenharia Tecidual/métodos , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Feminino , Fibrina/farmacologia , Imuno-Histoquímica , Implantes Experimentais , Neuritos/efeitos dos fármacos , Oxidopamina , Doença de Parkinson/terapia , Ratos Sprague-Dawley , Rotação
7.
J Clin Oncol ; 21(22): 4105-11, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14559891

RESUMO

PURPOSE: This analysis evaluated whether the antiemetic efficacy of the NK1 receptor antagonist aprepitant (EMEND trade mark, Merck, Whitehouse Station, NJ) plus standard antiemetics could be sustained for up to six cycles of cisplatin-based chemotherapy. PATIENTS AND METHODS: Patients receiving cisplatin > or = 70 mg/m2 were blindly assigned to receive one of the following three regimens: (1) aprepitant 375 mg 1 hour before cisplatin on day 1 and aprepitant 250 mg on days 2 to 5 (n = 35); (2) aprepitant 125 mg before cisplatin and aprepitant 80 mg on days 2 to 5 (n = 81); or (3) placebo before cisplatin on days 2 to 5 (n = 86). All groups received ondansetron 32 mg and dexamethasone 20 mg before cisplatin, and dexamethasone 8 mg on days 2 to 5. The primary end point was complete response (no emesis and no rescue therapy) over 5 days following cisplatin in up to six cycles. A cumulative probability analysis using a model for transitional probabilities was used to analyze the data. The aprepitant 375/250-mg regimen was discontinued early in light of new pharmacokinetic data. RESULTS: In the first cycle, 64% of patients in the aprepitant group and 49% in the standard therapy group had a complete response. Thereafter, complete response rates for the aprepitant group were still 59% by cycle 6, but decreased to 34% by cycle 6 for the standard therapy group. Reasons for discontinuation were similar across treatment groups. CONCLUSION: Compared with patients who received standard therapy, those who received only the aprepitant regimen had better and more sustained protection against chemotherapy-induced nausea and vomiting over multiple cycles.


Assuntos
Antineoplásicos/efeitos adversos , Morfolinas/uso terapêutico , Náusea/prevenção & controle , Neoplasias/tratamento farmacológico , Antagonistas dos Receptores de Neurocinina-1 , Vômito/prevenção & controle , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antieméticos/uso terapêutico , Aprepitanto , Cisplatino/efeitos adversos , Dexametasona/uso terapêutico , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Neoplasias/patologia , Resultado do Tratamento , Vômito/induzido quimicamente
8.
J Appl Physiol (1985) ; 98(3): 940-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15531569

RESUMO

We tested the hypothesis that increased intraluminal shear stress induces endothelial nitric oxide (NO) synthase (eNOS) mRNA expression and improves endothelium-dependent dilation in senescent soleus muscle feed arteries (SFA) by increasing NO production. SFA were isolated from young (4 mo) and old (24 mo) male Fischer 344 rats and cannulated with two resistance-matched glass micropipettes. SFA were exposed to no flow (NF), low flow (LF), intermediate flow (IF), or high flow (HF) for 4 h. Mean intraluminal shear stress ranged from 0 to 82 dyn/cm(2). At the end of the 4-h treatment period, eNOS mRNA expression was assessed in each SFA. eNOS mRNA expression was significantly lower in old NF SFA than in young NF SFA. In old SFA, eNOS mRNA expression was induced by IF (+154%) and HF (+136%), resulting in a level of expression that was not different from that of young SFA. In a separate series of experiments, SFA were pretreated with NF or HF for 4 h, and endothelial function was assessed by examining vasodilator responses to ACh. ACh-induced dilation was less in old NF SFA than young NF SFA. Pretreatment with HF improved ACh-induced dilation in old SFA such that the response was similar to that of young SFA. In the presence of N(omega)-nitro-L-arginine to inhibit NOS, ACh-induced dilation was inhibited in old HF SFA such that the response was no longer greater than that of old NF SFA. These results indicate that increased intraluminal shear stress induces eNOS mRNA expression and improves endothelium-dependent dilation in senescent SFA by increasing NO production.


Assuntos
Envelhecimento/fisiologia , Artérias/fisiologia , Endotélio Vascular/fisiologia , Mecanotransdução Celular/fisiologia , Músculo Esquelético/irrigação sanguínea , Óxido Nítrico Sintase/metabolismo , Vasodilatação/fisiologia , Animais , Artérias/citologia , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Regulação da Expressão Gênica/fisiologia , Músculo Esquelético/metabolismo , Óxido Nítrico Sintase Tipo III , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos F344 , Resistência ao Cisalhamento , Estresse Mecânico
9.
Eur J Cancer ; 40(3): 403-10, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14746859

RESUMO

In early clinical trials, the NK(1) receptor antagonist, aprepitant (EMEND(R)) was shown to improve the protection provided by the best available therapy (hereafter referred to as 'standard therapy': a 5-HT(3) receptor antagonist and dexamethasone) against chemotherapy-induced nausea and vomiting over multiple cycles of cisplatin-based chemotherapy. To further study the sustainment of antiemetic efficacy of aprepitant plus standard therapy over more than one cycle of chemotherapy, we examined combined data from the multiple cycles extensions of two phase III clinical trials of oral aprepitant plus standard therapy for the prevention of chemotherapy-induced nausea and vomiting. Data were pooled from two multicentre, randomised, double-blind, placebo-controlled studies with identical design and treatment regimens. Cancer patients receiving a first cycle of cisplatin-based (>or=70 mg/m(2)) chemotherapy were randomised to one of two treatment groups as follows: the standard therapy group received ondansetron 32 mg intravenously (i.v.) and dexamethasone 20 mg on day 1 and dexamethasone 8 mg twice daily (b.i.d.) on days 2-4. The aprepitant group received aprepitant 125 mg, ondansetron 32 mg i.v., and dexamethasone 12 mg on day 1, aprepitant 80 mg and dexamethasone 8 mg on days 2-3, and dexamethasone 8 mg on day 4. Patients had the option to receive the same blinded treatment for up to five additional cycles. The analysis used a combined exploratory endpoint of no emesis and no significant nausea (i.e. nausea which interfered with a patient's normal activities) over the 5 days following cisplatin, for up to six cycles of chemotherapy. A cumulative probabilities approach incorporating a model for transitional probabilities was used to analyse the data. Tolerability was assessed by reported adverse events and physical and laboratory assessments. Baseline characteristics, reasons for discontinuation, and drop-out rates were similar between groups. In every cycle, the estimated probabilities (rates) of no emesis and no significant nausea were significantly higher (P<0.006) in the aprepitant group: in the first cycle, rates were 61% in the aprepitant group (N=516) and 46% in the standard therapy group (N=522), and thereafter, rates for the aprepitant regimen remained higher throughout (59% (N=89) versus 40% (N=78) for the standard therapy, by cycle 6). Repeated dosing with aprepitant over multiple cycles was generally well tolerated. Compared with patients who received standard therapy alone (a 5-HT(3) antagonist plus dexamethasone), those who received aprepitant in addition to standard therapy had consistently better antiemetic protection that was well maintained over multiple cycles of highly emetogenic chemotherapy


Assuntos
Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Morfolinas/uso terapêutico , Náusea/prevenção & controle , Antagonistas dos Receptores de Neurocinina-1 , Vômito/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antieméticos/efeitos adversos , Aprepitanto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morfolinas/efeitos adversos , Neoplasias/tratamento farmacológico , Resultado do Tratamento
10.
Eur J Cancer ; 39(10): 1395-401, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12826042

RESUMO

Little information exists on the functional impact of effective antiemetic protection. In the present study, the Functional Living Index-Emesis (FLIE), was used to assess patient-reported impact of chemotherapy-induced nausea and vomiting (CINV) after administration of a new NK-1 receptor antagonist (aprepitant). Cisplatin-treated patients in a double-blind randomised trial received either aprepitant+dexamethasone+ondansetron on day 1 and aprepitant+dexamethasone on days 2-5 or standard antiemetic therapy (dexamethasone and ondansetron on day 1 and dexamethasone on days 2-5). Emetic events, nausea ratings and rescue medications were recorded in a 5-day diary and the FLIE was completed on day 6. Compared with standard therapy, significantly more patients treated with the high dose aprepitant regimen achieved a Complete Response (71 vs 44%, P<0.001) and also reported no impact on daily life as indicated by the FLIE total score (84 vs 66%, P<0.01). Use of the FLIE demonstrated that improved control of emesis was highly effective in reducing the impact of CINV on patients' daily lives.


Assuntos
Antieméticos/uso terapêutico , Morfolinas/uso terapêutico , Náusea/prevenção & controle , Receptores da Neurocinina-1/uso terapêutico , Inquéritos e Questionários , Vômito/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Aprepitanto , Cisplatino/efeitos adversos , Dexametasona/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Neoplasias/tratamento farmacológico , Ondansetron/uso terapêutico , Vômito/induzido quimicamente
11.
Atherosclerosis ; 167(1): 15-23, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12618264

RESUMO

No studies exist concerning the ability of the plasma membrane Ca(2+) pump (PMCA), sarcoplasmic reticulum Ca(2+) pump (SERCA) and Na(+)-Ca(2+) exchanger (NCX) to regulate myoplasmic Ca(2+) (Ca(m)) in vascular smooth muscle cells from diabetic individuals with dyslipidemia. We tested the hypothesis that diabetic dyslipidemia would increase vascular smooth muscle cells to buffer Ca(m). Cells were isolated from the coronary artery of male Yucatan pigs treated for 20 weeks with: (1) a low fat diet (control group); (2) a high fat/cholesterol diet (F group); or (3) alloxan-induced diabetic pigs fed the high fat diet (DF group). The maximum Ca(m) response to a depolarizing 80 mM KCl (80 K) solution was evaluated in the absence and presence of thapsigargin (TSG; inhibits SERCA) and low Na (inhibits NCX). In response to 80 K alone, there was no difference in the Ca(m) response between groups. In the presence of TSG, the 80 K response decreased by 43% in the DF group; TSG did not affect the 80 K response in the control and F groups. When exposed to both TSG and low Na, the 80 K response also decreased by 55% in the DF group. This suggests increased Ca(m) buffering by the PMCA and/or mitochondria in the DF group when SERCA and NCX are inhibited. Compared to the control and F groups, low Na alone elicited a 50% lower Ca(m) amplitude in the DF group, which was reversed with TSG treatment; this suggests that SERCA activity is increased in DF pigs. Western blots also indicated a 7-fold increase in the approximately 115 kDa band density of an anti-SERCA2 antibody in DF compared to control pigs. This is the first report to demonstrate increased Ca(2+) buffering, specifically by SERCA, in vascular smooth muscle cells from diabetic individuals with dyslipidemia.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , Hiperlipidemias/enzimologia , Miócitos de Músculo Liso/metabolismo , Tapsigargina/farmacologia , Análise de Variância , Animais , Western Blotting , Soluções Tampão , ATPases Transportadoras de Cálcio/efeitos dos fármacos , Células Cultivadas , Vasos Coronários/metabolismo , Vasos Coronários/fisiopatologia , Diabetes Mellitus Experimental , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Hiperlipidemias/fisiopatologia , Miócitos de Músculo Liso/efeitos dos fármacos , Probabilidade , Valores de Referência , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Sensibilidade e Especificidade , Suínos
12.
J Appl Physiol (1985) ; 93(5): 1685-90, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12381754

RESUMO

We tested the hypothesis that aging decreases endothelium-dependent vasodilation in feed arteries perfusing rat skeletal muscle. In addition, we tested the hypothesis that attenuated vasodilator responses are associated with decreased endothelial nitric oxide synthase (eNOS) and superoxide dismutase-1 (SOD-1) expression. Soleus feed arteries (SFA) and gastrocnemius feed arteries (GFA) were isolated from young (4 mo) and old (24 mo) male Fischer 344 rats. Feed arteries from the right hindlimb were cannulated with two glass micropipettes for examination of endothelium-dependent [acetylcholine (ACh)] and endothelium-independent [adenosine (Ado) or sodium nitroprusside (SNP)] vasodilator function. Feed arteries from the left hindlimb were frozen and used to assess eNOS and SOD-1 protein and mRNA expression. In SFA, endothelium-dependent dilation to ACh was reduced in old rats (0.9 +/- 0.04 vs. 0.8 +/- 0.03), whereas dilator responses to Ado and SNP were similar in SFA of young and old rats. In GFA, vasodilator responses to ACh, Ado, and SNP were not altered by age. eNOS and SOD-1 protein expression declined with age in SFA (-71 and -54%, respectively) but not in GFA. eNOS and SOD-1 mRNA expression were not altered by age in SFA or GFA. Collectively, these data indicate aging induces muscle-specific impairment of endothelium-dependent vascular function in SFA.


Assuntos
Envelhecimento/fisiologia , Endotélio Vascular/fisiologia , Músculo Esquelético/irrigação sanguínea , Vasodilatação/fisiologia , Animais , Artérias/fisiologia , Masculino , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III , Ratos , Ratos Endogâmicos F344 , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1
13.
J Appl Physiol (1985) ; 95(5): 2164-70, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12897037

RESUMO

We tested the hypothesis that endothelium-dependent dilation in soleus muscle feed arteries (SFA) is impaired by aging due to attenuated nitric oxide (NO)-mediated vasodilation. SFA were isolated from young (4 mo) and old (24 mo) male Fischer 344 rats and cannulated with two glass micropipettes for examination of endothelium-dependent [flow or acetylcholine (ACh)] and endothelium-independent [sodium nitroprusside (SNP)] vasodilator function. Flow- and ACh-induced dilation was significantly attenuated by age, whereas dilation to SNP was not compromised. To determine the mechanism(s) by which aging affected dilator responses to flow and ACh, dilation was assessed in the presence of Nomega-nitro-L-arginine (L-NNA; to inhibit NO synthase), indomethacin (Indo; to inhibit cyclooxygenase), and L-NNA + Indo. In the presence of L-NNA, Indo, or L-NNA + Indo, flow-induced dilation was inhibited in young SFA, resulting in a response to flow that was no longer greater than old SFA. In the presence of L-NNA or Indo, ACh-induced dilation was not significantly inhibited in young or old SFA; however, double blockade with L-NNA + Indo inhibited ACh-induced dilation in young SFA such that the response to ACh was no longer greater than old SFA. Collectively, these data indicate that aging impairs vasodilator responses in SFA by attenuating NO- and prostacyclin-mediated, endothelium-dependent, dilation.


Assuntos
Envelhecimento/metabolismo , Endotélio Vascular/metabolismo , Epoprostenol/metabolismo , Músculo Esquelético/irrigação sanguínea , Óxido Nítrico/metabolismo , Acetilcolina/farmacologia , Animais , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Indometacina/farmacologia , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Nitroarginina/farmacologia , Nitroprussiato/farmacologia , Ratos , Ratos Endogâmicos F344 , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Vasodilatadores/farmacologia
14.
Brain Res ; 975(1-2): 196-206, 2003 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-12763608

RESUMO

Pregnancy results in attenuated baroreflex mediated sympathoexcitatory responses which may be due to potentiation of gamma-aminobutyric acid (GABA) inhibition in the rostral ventrolateral medulla (RVLM). The major metabolite of progesterone, 3alpha-hydroxy-dihydroprogesterone (3alpha-OH-DHP), which is elevated in pregnancy, is a potent neurosteroid positive modulator of GABA(A) receptors, and sensitivity of GABA(A) receptors to 3alpha-OH-DHP is dependent on the receptor subunit composition. The purpose of this study was to evaluate the GABA(A) alpha(1) and alpha(2) receptor subunit mRNA and protein expression in the RVLM of nonpregnant and late term pregnant rats. Micropunches of RVLM were collected from nonpregnant and late term pregnant rats and the expression levels of GABA(A) alpha(1) and alpha(2) receptor subunits were analyzed using quantitative competitive reverse transcriptase polymerase chain reaction (RT-PCR) and immunoblot techniques. The competitive RT-PCR analysis allows comparison of expression levels between different mRNA, and the mRNA expression level of GABA(A) alpha(1) was several hundred fold greater than GABA(A) alpha(2) in both groups. However, this relative distribution of GABA(A) alpha(1) and alpha(2) receptor subunits protein or mRNA expression was not altered in late term pregnant compared to nonpregnant rats. These data demonstrate, that within the RVLM of both nonpregnant and late term pregnant rats, the relative expression levels of GABA(A) alpha(1,2) receptor subunits favor GABA(A) receptors susceptible to positive modulation by progesterone metabolites.


Assuntos
Bulbo/metabolismo , Prenhez/metabolismo , Receptores de GABA-A/biossíntese , Animais , Western Blotting , DNA Complementar/biossíntese , DNA Complementar/genética , Feminino , Gliceraldeído-3-Fosfato Desidrogenases/biossíntese , Gliceraldeído-3-Fosfato Desidrogenases/genética , Processamento de Imagem Assistida por Computador , Feniletanolamina N-Metiltransferase/biossíntese , Gravidez , Subunidades Proteicas/biossíntese , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tirosina 3-Mono-Oxigenase/biossíntese
15.
J Biochem Biophys Methods ; 50(2-3): 233-43, 2002 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-11741710

RESUMO

Structural analysis of native or recombinant membrane transport proteins has been hampered by the lack of effective methodologies to purify sufficient quantities of active protein. We addressed this problem by expressing a polyhistidine tagged construct of the cardiac sodium-calcium exchanger (NCX1) in Trichoplusia ni larvae (caterpillars) from which membrane vesicles were prepared. Larvae vesicles containing recombinant NCX1-his protein supported NCX1 transport activity that was mechanistically not different from activity in native cardiac sarcolemmal vesicles although the specific activity was reduced. SDS-PAGE and Western blot analysis demonstrated the presence of both the 120 and 70 kDa forms of the NCX1 protein. Larvae vesicle proteins were solubilized in sodium cholate detergent and fractionated on a chelated Ni(2+) affinity chromatography column. After extensive washing, eluted fractions were mixed with soybean phospholipids and reconstituted. The resulting proteoliposomes contained NCX1 activity suggesting the protein retained native conformation. SDS-PAGE revealed two major bands at 120 and 70 kDa. Purification of large amounts of active NCX1 via this methodology should facilitate biophysical analysis of the protein. The larva expression system has broad-based application for membrane proteins where expression and purification of quantities required for physical analyses is problematic.


Assuntos
Trocador de Sódio e Cálcio/genética , Trocador de Sódio e Cálcio/isolamento & purificação , Animais , Baculoviridae/genética , Bovinos , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Expressão Gênica , Larva , Mariposas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
16.
J Pediatr Surg ; 22(3): 240-2, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3559868

RESUMO

Muscle strips from the fundus, trigone, and distal ureter obtained from children at operation for vesicoureteric reflux were studied using histochemical and immunohistochemical methods, and electrical nerve stimulation in an organ bath. A rich supply of cholinergic nerves was found and the transmitter causing contraction of the detrusor muscle was regarded as being acetylcholine. The adrenergic innervation was very sparse except around the ureteric orifices. No contractile alpha-adrenoceptors could be detected but beta-receptor-mediated relaxation was found. The type was not beta 1 or beta 2, suggesting a third type of beta-receptor. Peptidergic nerves containing vasoactive intestinal peptide (VIP) were demonstrated in a few nerve terminals. No nerves containing enkephalin, somatostatin, or substance P were found. VIP affected the detrusor muscle, indicating a possible role as a modulator of transmitter action. Imipramine, used for enuresis, had no anticholinergic effect on the bladder in the doses used clinically. The anticholinergic and calcium antagonistic drug terodiline inhibited all muscle activity, making it suitable for treatment of diurnal enuresis.


Assuntos
Bexiga Urinária/inervação , Refluxo Vesicoureteral/fisiopatologia , Acetilcolinesterase/análise , Fibras Adrenérgicas/anatomia & histologia , Fibras Adrenérgicas/fisiopatologia , Butilaminas/farmacologia , Criança , Pré-Escolar , Fibras Colinérgicas/anatomia & histologia , Fibras Colinérgicas/fisiopatologia , Estimulação Elétrica , Histocitoquímica , Humanos , Técnicas In Vitro , Lactente , Isoproterenol/farmacologia , Contração Muscular/efeitos dos fármacos , Norepinefrina/farmacologia , Fenilefrina/farmacologia , Ureter/inervação , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiopatologia , Peptídeo Intestinal Vasoativo/análise , Peptídeo Intestinal Vasoativo/farmacologia
17.
Med Klin (Munich) ; 85(6): 361-5, 1990 Jun 15.
Artigo em Alemão | MEDLINE | ID: mdl-2377146

RESUMO

32 patients with HIV infection presenting with fever or abnormal chest radiograph or both were investigated at the University Hospital of Mainz (FRG). Fiberoptic bronchoscopy with bronchoalveolar lavage and transbronchial biopsy was undertaken in each patient, additionally other methods were used for isolating pathogens (i.e. urine sample, stool and blood culture etc.). In 26 patients one or more complicating diseases were documented, in six persons no reason for fever or pulmonary symptoms could be detected. 21 patients had a pulmonary complication, 13 were found to have pneumocystis carinii pneumonia. Bacterial lung diseases were diagnosed in seven individuals (three caused by M. tuberculosis, two by S. pneumoniae, one by E. cloacae and one by S. aureus). One nonspecific interstitial pneumonitis was diagnosed. By other diagnostic procedures 25 non-pulmonary complications were established. -Fiberoptic bronchoscopy is most accurate for the detection of pulmonary pathogens in HIV infected persons when transbronchial biopsy and bronchoalveolar lavage is combined, especially in pneumocystis carinii pneumonia. Bronchoscopy should be performed also if the chest radiograph is normal.


Assuntos
Líquido da Lavagem Broncoalveolar , Broncoscopia , Infecções por HIV/complicações , Neoplasias Pulmonares/complicações , Linfoma não Hodgkin/complicações , Infecções Oportunistas/complicações , Pneumonia/complicações , Sarcoma de Kaposi/complicações , Adolescente , Adulto , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Linfoma não Hodgkin/diagnóstico , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/diagnóstico , Pneumonia/diagnóstico , Sarcoma de Kaposi/diagnóstico
18.
Lakartidningen ; 88(10): 850-1, 1991 Mar 06.
Artigo em Sueco | MEDLINE | ID: mdl-2008130

RESUMO

Efficacy and tolerance of the anticholinergic calcium antagonist, terodiline (Mictrol), were investigated in a placebo-controlled double-blind cross-over study of 42 children with diurnal enuresis. At a daily dosage of 25 mg, terodiline was well tolerated and, as compared with placebo, resulted in a statistically significant reduction in the daily frequency of wetting. Thus the findings show terodiline to be effective in the treatment of diurnal enuresis, an added advantage being the low incidence of side effects. A full report in English is given in Scand J Prim Health Care 1988; 6:119-24.


Assuntos
Butilaminas/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Enurese/tratamento farmacológico , Adolescente , Butilaminas/administração & dosagem , Bloqueadores dos Canais de Cálcio/administração & dosagem , Criança , Pré-Escolar , Método Duplo-Cego , Avaliação de Medicamentos , Humanos
19.
Scand J Urol Nephrol Suppl ; 87: 59-61, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6599420

RESUMO

The effect of terodiline, a drug with both anticholinergic and calcium antagonistic properties, was studied in vitro on muscle strips from the urinary bladder of children and in vivo in children with diurnal enuresis. Terodiline inhibited all muscle activity in the urinary bladder strips whether induced by nerve stimulation or by drugs with different mechanisms of action. In most children treated the daytime enuresis disappeared completely, with a larger amount of urine at micturition and a lower voiding frequency. Cystometry indicated increased functional bladder capacity and decreased premicturition pressure.


Assuntos
Butilaminas/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Enurese/tratamento farmacológico , Adolescente , Butilaminas/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Criança , Pré-Escolar , Humanos , Técnicas In Vitro , Bexiga Urinária/efeitos dos fármacos
20.
J Neurosci Methods ; 197(1): 48-55, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21310182

RESUMO

Cell transplant and gene therapies are promising approaches to many disorders of the nervous system. In studies involving cell transplants to the brain or nervous system, expression of green fluorescent protein (GFP) is commonly used to label cells, allowing their identification and histological assessment even after long post-operative survival times. Techniques employing viral tracing or reporter genes also commonly use GFP to label cells. Here, we document the presence of a subpopulation of green autofluorescent cells in the cortex and hippocampus of formaldehyde fixed, cryosectioned rat brains aged 3-9 months. Using standard microscopic fluorescence imaging techniques, we acquired clear images of green autofluorescent cells, complete with extensive processes, which appear to be well integrated into the host tissue. Treatment of brain sections with sodium borohydride followed by cupric sulfate in ammonium acetate buffer reduced background and cellular autofluorescence throughout sections but, especially in hippocampus, did not eliminate considerable green fluorescence in a subset of neurons. This autofluorescence was weak and would therefore pose a problem only when cells weakly express GFP or when few labeled cells survive. We suggest that investigators be aware of the potential for false positives, especially if the cells expressing GFP are expected to migrate widely from the transplant site. Parallel sections from naïve brains should regularly be processed and imaged alongside experimental brain sections, and anti-GFP immunohistochemistry should be performed to ensure that true GFP+ signals are imaged instead of endogenous autofluorescent neurons.


Assuntos
Artefatos , Encéfalo/citologia , Proteínas de Fluorescência Verde/química , Neurônios/citologia , Coloração e Rotulagem/normas , Animais , Encéfalo/metabolismo , Reações Falso-Positivas , Imunofluorescência , Genes Reporter/fisiologia , Proteínas de Fluorescência Verde/genética , Microscopia de Fluorescência/métodos , Microscopia de Fluorescência/normas , Neurônios/química , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem/métodos
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