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1.
J Cell Biol ; 95(1): 105-17, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7142282

RESUMO

The pathway and kinetics of the secretory protein transport in rat lacrimal exorbital gland have been established by an in vitro time-course radioautographic study of pulse-labeled protein secretion. The colchicine-sensitive steps have been localized by using the drug at various times with respect to the pulse labeling of proteins. Colchicine (10 microM) does not block any step of the secretory protein transport, but when introduced before the pulse it decreases the transfer of labeled proteins from the rough endoplasmic reticulum to the Golgi area, suppressing their temporary accumulation in the Golgi area before any alteration of this organelle is detectable. Moreover, colchicine inhibits protein release only from the secretory granules formed in its presence because the peroxidase discharge is diminished 1 h after colchicine addition, and the secretion of newly synthesized proteins is strongly inhibited only when colchicine is introduced before secretory granule formation. Morphometric studies show that there is a great increase of secondary lysosomes, related to crinophagy, as early as 40-50 min after colchicine is added. However, changes in lysosomal enzymatic activities remained biochemically undetectable. We conclude that: (a) the labile microtubular system does not seem indispensable for protein transport in the rough endoplasmic reticulum-Golgi area but may facilitate this step, perhaps by maintaining the spatial organization of this area; and (b) in the lacrimal gland, colchicine inhibits protein release not by acting on the steps of secretion following the secretory granule formation, but by acting chiefly on the steps preceding secretory granule formation, perhaps by making the secretory granules formed in its presence incapable of discharging their content.


Assuntos
Colchicina/farmacologia , Aparelho Lacrimal/metabolismo , Microtúbulos/fisiologia , Proteínas/metabolismo , Taxa Secretória/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Carbacol/farmacologia , Retículo Endoplasmático/metabolismo , Aparelho Lacrimal/ultraestrutura , Lisossomos/efeitos dos fármacos , Masculino , Microscopia Eletrônica , Peso Molecular , Biossíntese de Proteínas , Ratos
2.
Rev Mal Respir ; 25(7): 829-38, 2008 Sep.
Artigo em Francês | MEDLINE | ID: mdl-18946408

RESUMO

INTRODUCTION: Intensive efforts should be made to diagnose the hyperventilation syndrome (HVS) at an early stage as this will prevent stigmatisation and reinforcement of symptoms. It will also prevent children from undergoing unnecessary medical examinations and treatment. A diagnostic questionnaire should be useful for this purpose. METHODS: We administered a questionnaire with 16 respiratory symptoms and 23 non respiratory symptoms to 25 children with HVS alone, 20 with asthma and HVS, and two control groups: 20 children with asthma without HVS and 20 presenting with trauma. For each symptom a visual analogue scale (VAS) was completed. The symptoms for which the mean VAS values were significantly different between the children with HVS and the controls were subject to principal component analysis after varimax rotation with Kaiser normalisation. RESULTS: There was no significant difference in symptoms between HVS children with or without asthma. The five major respiratory symptoms were: throat-clearing, sniffing, difficulty in breathing in, sighing and yawning. The combined sensitivity of those symptoms was 99%, the combined specificity 24%. The five major non-respiratory symptoms were: anxiety, difficulty in going to sleep, general fatigue, abdominal pain, and joint pains. The combined sensitivity of those symptoms was 99%, the combined specificity 36%. CONCLUSIONS: We performed a simplified diagnostic questionnaire for HVS in healthy and asthmatic children and found 5 respiratory and 5 non-respiratory symptoms of significance.


Assuntos
Asma/diagnóstico , Hiperventilação/diagnóstico , Inquéritos e Questionários , Adolescente , Fatores Etários , Asma/psicologia , Criança , Feminino , Humanos , Hiperventilação/psicologia , Masculino , Medição da Dor , Sensibilidade e Especificidade , Fatores Sexuais , Síndrome , Adulto Jovem
3.
Ann Fr Anesth Reanim ; 25(10): 1030-3, 2006 Oct.
Artigo em Francês | MEDLINE | ID: mdl-17005352

RESUMO

OBJECTIVE: To test a high-frequency jet ventilator, the Mistral (Acutronic Laboratory) on a lung model. METHODS: The jet ventilator Mistral was tested with two connectors (7 and 20 ml) and four catheters. Pressure and flow measurements were performed by varying the driving pressure (1 to 3 bars), the I/T ratio (0.25, 0.35, 0.45) and the frequency (1 to 5 Hz). Recorded data were: the volume delivered by the ventilator, the pressure measured in the connecting line between the ventilator and the injector and the difference between the end expiratory pressure measured by the ventilator through the injector and the tracheal pressure. RESULTS: An increase in driving pressure induced a proportional increase in minute volume whatever the injection catheter used. After insufflation, when a Seldicath catheter was used, the pressure decrease was the slowest and the time constant the longest. Increase in frequency or I/T ratio, particularly beyond 0.35, was associated with an increase of the end expiratory pressure measured by the respirator. The gradient of pressure measured by the respirator and by an external sensor was lower with the 7 ml connector whatever the catheter used, and was larger with the Seldicath catheter. CONCLUSION: The use of a low volume connector should be preferred, because it allows the measurement of the end expiratory pressure for a larger range of driving pressure, expiratory time and catheters. The performances of the Seldicath catheter are below those of the other catheters studied.


Assuntos
Ventilação em Jatos de Alta Frequência , Ventilação em Jatos de Alta Frequência/instrumentação , Pressão
4.
Ann Fr Anesth Reanim ; 25(9): 1000-2, 2006 Sep.
Artigo em Francês | MEDLINE | ID: mdl-16891086

RESUMO

If the cardiac injuries are frequent after closed chest traumatism, the cardiac injuries after abdominal closed traumatism are unusual but serious. We report the case of a right auricular rupture associated with a liver injury after a closed abdominal traumatism. The diagnosis was suspected on the TDM and confirmed by echocardiography. An emergency sternotomy was performed due to sudden haemodynamic instability. The initial clinical signs are often misleading. However the diagnosis must be made quickly and the treatment begun without delay.


Assuntos
Átrios do Coração , Ruptura Cardíaca , Ferimentos não Penetrantes/complicações , Traumatismos Abdominais/etiologia , Acidentes de Trânsito , Adulto , Ecocardiografia , Feminino , Ruptura Cardíaca/diagnóstico por imagem , Ruptura Cardíaca/cirurgia , Humanos , Fígado/lesões , Esterno/cirurgia , Ferimentos não Penetrantes/diagnóstico por imagem
5.
Cancer Radiother ; 20(3): 236-47, 2016 May.
Artigo em Francês | MEDLINE | ID: mdl-27133378

RESUMO

The purpose of this review was to summarize recent data about lastest retrospective and prospective studies dealing with radiotherapy of non-Hodgkin lymphoma, in order to precise the schedule and the role of this treatment. A systematic review was done by searching studies on the website http://www.pubmed.gov (Medline) using the following keywords: radiotherapy, radiation therapy, non-Hodgkin lymphoma. The management of non-Hodgkin lymphoma varies a lot according to the histological type and stage. The dose of radiotherapy has been studied in only one randomized trial, which concluded that there was no difference between the low dose and the high dose arms. Radiotherapy is a very good option in follicular, cutaneous, digestive or orbital non-Hodgkin lymphoma. A recent post hoc analysis of randomized trials on radiotherapy for high-grade non-Hodgkin lymphoma strongly suggested a benefit of additional radiotherapy after chemotherapy in some situations. Radiotherapy of low-grade non-Hodgkin lymphoma is a very good option, while its use on high-grade non-Hodgkin lymphoma is sometimes recommended but further randomized trials are ongoing to better understand its role.


Assuntos
Linfoma não Hodgkin/radioterapia , Humanos , Linfoma de Zona Marginal Tipo Células B/radioterapia , Linfoma Folicular/radioterapia , Estudos Prospectivos , Radioterapia/métodos , Estudos Retrospectivos , Neoplasias Cutâneas/radioterapia
6.
Biochim Biophys Acta ; 844(2): 158-66, 1985 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-2857578

RESUMO

Cytochalasin D altered the kinetics of peroxidase and radiolabeled protein discharge from rat exorbital lacrimal glands in vitro, in response to various secretagogues. The changes were different with each inducer. The discharge due to isoproterenol was immediately inhibited by 95%; the discharge evoked by noradrenaline via alpha-adrenergic receptors was progressively reduced and was inhibited by 50% after 30 min, whereas that evoked by carbachol was not influenced during the initial discharge period and was diminished by only 30% after 30 min. When calcium was removed from the incubation medium, the secretory responses were lowered and the inhibitory effect of cytochalasin D was still observed. The rate of protein discharge inhibition was related to the dose and was maximal with 2 X 10(-6) M cytochalasin D when the discharge resulted from cholinergic, alpha- or beta-adrenergic or dibutyryl cAMP stimulation. Cytochalasin D did not impair cellular energetics nor other stimulations induced through muscarinic or adrenergic receptors. Cytochalasin D effects could be related to interaction with actin, leading to the inhibition of the release of proteins into the incubation medium following the activation of the adrenergic system.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Citocalasinas/metabolismo , Aparelho Lacrimal/efeitos dos fármacos , Proteínas/metabolismo , Animais , Bucladesina/farmacologia , Calcimicina/farmacologia , Carbacol/farmacologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Citocalasina D , Citoesqueleto/metabolismo , Relação Dose-Resposta a Droga , Cinética , Masculino , Norepinefrina/farmacologia , Peroxidases/metabolismo , Propranolol/farmacologia , Ratos , Ratos Endogâmicos
7.
Cell Signal ; 4(1): 111-9, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1571202

RESUMO

The molecular heterogeneity of protein kinase C (PKC) is now widely documented. In our first report, we characterized the rat lacrimal gland PKC along with a phorbol 12-myristate 13-acetate (PMA)-activated and phospholipid-independent protein kinase activity [Mauduit P., Zoukhri D. and Rossignol B. (1989) Fedn Eur. biochem. Socs Lett. 252, 5-11. In this work, we show that when the rat lacrimal gland cytosolic fraction is chromatographed on hydroxyapatite, only one peak of PKC activity can be detected. Comparison with a rat brain cytosolic fraction indicated that it is PKC-alpha which is expressed in the rat lacrimal gland. This result was confirmed by the use of polyclonal antibodies raised against rat brain PKC-alpha, beta and gamma isoforms. We also provide evidence that free arachidonic acid activates PKC, as does PMA, in a calcium and phospholipid-free system.


Assuntos
Aparelho Lacrimal/enzimologia , Fosfolipídeos/metabolismo , Proteína Quinase C/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Alcaloides/farmacologia , Animais , Ácidos Araquidônicos/metabolismo , Cromatografia DEAE-Celulose , Ativação Enzimática , Masculino , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/química , Ratos , Ratos Endogâmicos , Estaurosporina
8.
Arch Pediatr ; 12(12): 1742-7, 2005 Dec.
Artigo em Francês | MEDLINE | ID: mdl-16226880

RESUMO

Hyperventilation syndrome is frequent in adults. There are only very few and very ancient publications in children. Diagnosis is sometimes difficult, because the symptoms often mimic those of organic diseases. Hyperventilation syndrome and organic diseases, especially asthma, often coincide. Intensive efforts should be made to diagnose hyperventilation syndrome at an early stage because this will prevent stigmatization and fixation of symptoms and disease, and also prevent children from undergoing unnecessary medical examinations and therapies. The authors review the literature about hyperventilation syndrome in children.


Assuntos
Asma/complicações , Hiperventilação/etiologia , Criança , Doença Crônica , Diagnóstico Diferencial , Humanos , Hiperventilação/diagnóstico , Hiperventilação/fisiopatologia , Hiperventilação/terapia , Prognóstico , Fatores de Risco , Síndrome
9.
Arch Pediatr ; 12(12): 1788-96, 2005 Dec.
Artigo em Francês | MEDLINE | ID: mdl-16126376

RESUMO

Written action plans for asthma have been recommended for many years. However, despite the fact that their effectiveness has been demonstrated, they are not used enough. The plans that we propose are serviceable and the method that we suggest makes them easy to use in the treatment of asthmatic children. These plans are made for patients who do not use a peak-flow meter (plans based on symptoms) and those who control this tool (plans based on peak expiratory flow).


Assuntos
Asma/terapia , Planejamento de Assistência ao Paciente , Educação de Pacientes como Assunto , Autocuidado , Criança , Humanos , Redação
10.
Ann Fr Anesth Reanim ; 24(8): 938-46, 2005 Aug.
Artigo em Francês | MEDLINE | ID: mdl-16009530

RESUMO

In the absence of thromboprophylaxis, coronary artery bypass graft surgery (CABG), intrathoracic surgery (thoracotomy or video-assisted thoracoscopy), abdominal aortic surgery and infrainguinal vascular surgery are high-risk surgeries for the development of venous thromboembolic events (VTE). The incidence of VTE following surgery of the intrathoracic aorta, carotid endarterectomy or mediastinoscopy is unknown. Data from the litterature are lacking to draw evidence-based recommandations for venous thromboprophylaxis after these three types of surgeries, and the following guidelines are but experts'opinions (Grade D recommendations). Thromboprophylaxis is recommended after CABG (Grade D), with either subcutaneous (SC) low molecular weight heparin (LMWH) or SC or intravenous (i.v.) unfractioned heparin (UH) (PTT target = 1.1-1.5 time control value) (both grade D). This may be combined with the use of intermittent pneumatic compression device (Grade B). After valve surgery. The anticoagulation recommended to prevent valve thrombosis is sufficient in order to prevent VTE. We recommend thromboprophylaxis with either LMWH or low dose UH to prevent VTE after aortic or lower limbs infrainguinal vascular surgery (both grade B and D). Vitamine K antagonists (VKA) are not recommended in this indication (Grade D). We recommend thromprophylaxis following intrathoracic surgery via thoracotomy or videoassisted thoracoscopy (grade C). Either subcutaneous LMWH or subcutaneous or i.v. low dose UH may be used (Grade C). Efficacy of intermittent pneumatic compression device has been demonstrated in a study (grade C). VKA are not recommended (grade D). No further recommendation regarding the duration of thromboprophylaxis after these three types of surgeries can be made.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Procedimentos Cirúrgicos Torácicos , Tromboembolia/prevenção & controle , Procedimentos Cirúrgicos Vasculares , Anestesia , Humanos , Medição de Risco
11.
Eur J Cell Biol ; 67(3): 227-37, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7588879

RESUMO

The role of microtubules in the exocrine secretory process is not yet well established. Contradictory effects of anti-microtubule drugs on intracellular transit and protein secretion have been reported. In this work we used microscopic techniques and pulse-chase experiments to compare the involvement of microtubules in the regulated secretory process of two rat exocrine glands: parotid and extraorbital lacrimal glands. In our experiments microtubules were either disrupted by nocodazole or stabilized by a taxoid, docetaxel (Taxotere). We show that the effect of nocodazole and docetaxel on the release of newly synthesized proteins is radically different in the two tissues; in parotid gland they only weakly affect protein release, triggered by stimulation of either muscarinic or beta-adrenergic receptors, but in lacrimal gland, they strongly inhibit protein secretion. This effect or lack of effect of the drug is independent of the signal transduction pathways involved by the different secretagogues used to trigger exocytosis. Furthermore, in lacrimal glands, studies on protein galactosylation (which occurs in the trans-Golgi compartment) indicate that postgalactosylation events are more sensitive to both drugs than pregalactosylation events. On the other hand, we show that the effect of nocodazole and docetaxel on the microtubule network is comparable on the two tissues. Finally, in lacrimal cells, we observed a scattering of the Golgi apparatus concomitant with the disruption of microtubules by nocodazole. We conclude from this study that microtubule network integrity is essential for protein secretion in lacrimal glands but not in parotid glands. This result implies that for the same physiological function, i.e. protein secretion, different mechanisms may be involved.


Assuntos
Glicoproteínas/metabolismo , Aparelho Lacrimal/metabolismo , Microtúbulos/efeitos dos fármacos , Nocodazol/farmacologia , Paclitaxel/análogos & derivados , Glândula Parótida/metabolismo , Taxoides , Animais , Bucladesina/farmacologia , Calcimicina/farmacologia , Carbacol/farmacologia , Docetaxel , Relação Dose-Resposta a Droga , Epinefrina/farmacologia , Imunofluorescência , Galactose/metabolismo , Isoproterenol/farmacologia , Aparelho Lacrimal/efeitos dos fármacos , Aparelho Lacrimal/ultraestrutura , Masculino , Paclitaxel/farmacologia , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/ultraestrutura , Dibutirato de 12,13-Forbol/farmacologia , Ratos , Ratos Sprague-Dawley
12.
FEBS Lett ; 314(3): 489-92, 1992 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-1468591

RESUMO

In order to test if phospholipase D (PLD) activity exists in the rat parotid gland, we took advantage of the fact that, in the presence of ethanol, PLD generates phosphatidylethanol (PEth) via a transphosphatidylation reaction. Lipid extracts of parotid acini prelabelled with [3H]myristic acid were analyzed by thin layer chromatography to determine [3H]phosphatidylethanol ([3H]PEth) formation. Carbamylcholine (1 mM) stimulated [3H]PEth formation in the presence of 2% ethanol, this effect was completely inhibited by atropine (10 microM). PMA (0.1-1 microM) and ionomycine (10 microM) also caused [3H]PEth generation. We conclude that a phospholipase D activity is present in the rat parotid gland and is regulated by muscarinic cholinergic receptors. Protein kinase C and calcium could also modulate this activity. This report provides the first evidence for the existence and receptor-linked regulation of phospholipase D in an exocrine gland, the rat parotid gland.


Assuntos
Glândula Parótida/enzimologia , Fosfolipase D/metabolismo , Receptores Muscarínicos/metabolismo , Animais , Cromatografia em Camada Fina , Ativação Enzimática , Ionóforos/farmacologia , Cinética , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Acetato de Tetradecanoilforbol/farmacologia
13.
FEBS Lett ; 363(1-2): 13-6, 1995 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-7537223

RESUMO

We have previously demonstrated that muscarinic and alpha-adrenergic receptors regulated a phospholipase D (PLD) activity in parotid glands. Since phorbol 12-myristate, 13-acetate (PMA) induced production of phosphatidylethanol (PEt), a stable metabolite widely accepted as marker of PLD activation, we have investigated the role of protein kinase C (PKC) in PLD stimulation in parotid acini. We tested PKC inhibitors on PEt formation elicited by PMA, by muscarinic and adrenergic agents. Staurosporine and chelerythrine, which act on the catalytic domain of PKC, did not allow the attribution of a role for PKC in PLD activation. Indeed, staurosporine did not affect PMA-mediated PLD activity and chelerythrine showed an important non-specific effect, independent of PKC inhibition. On the other hand, calphostin C, which acts on the regulatory domain of PKC, affected PMA- and receptor-mediated PLD stimulation. We attributed this effect to PKC inhibition and we suggested PKC involvement in PLD regulation in parotid gland. Since only PKC inhibitor acting on the regulatory part of the enzyme affected PLD activity, we also suggested that PKC could be involved in PLD activation through a pathway independent of the phosphorylation mechanism.


Assuntos
Glicerofosfolipídeos , Naftalenos , Glândula Parótida/enzimologia , Fosfolipase D/metabolismo , Proteína Quinase C/metabolismo , Alcaloides/farmacologia , Animais , Benzofenantridinas , Ativação Enzimática/efeitos dos fármacos , Masculino , Fenantridinas/farmacologia , Ácidos Fosfatídicos/metabolismo , Compostos Policíclicos/farmacologia , Proteína Quinase C/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Estaurosporina , Acetato de Tetradecanoilforbol/farmacologia
14.
FEBS Lett ; 153(1): 21-4, 1983 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-6298007

RESUMO

In rat lacrimal glands, Forskolin induces a dose-dependent [3H]protein release. This effect can be potentiated by papaverine. As for the other inducers whose effects on protein secretion are assumed to be cAMP-mediated, Forskolin secretion time course shows a latency. Isoproterenol decreases the Forskolin EC50 at least 60-times. On the other hand, Forskolin enhances the efficacy of isoproterenol without affecting its potency. As a whole, the data collected show that isoproterenol-induced [3H]protein secretion in rat lacrimal glands involved adenylate cyclase activation by coupling with beta-adrenergic receptors.


Assuntos
Diterpenos/farmacologia , Aparelho Lacrimal/metabolismo , Proteínas/metabolismo , Receptores Adrenérgicos beta/fisiologia , Receptores Adrenérgicos/fisiologia , Animais , Colforsina , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Isoproterenol/farmacologia , Aparelho Lacrimal/efeitos dos fármacos , Masculino , Papaverina/farmacologia , Ratos , Ratos Endogâmicos
15.
FEBS Lett ; 252(1-2): 5-11, 1989 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-2759232

RESUMO

The analysis of the cytosolic fraction from rat exorbital lacrimal gland with DEAE-cellulose ion-exchange chromatography showed the presence of a peak of protein kinase activity which was dependent on the presence of phosphatidylserine and diolein as well as calcium. This activity showed the same properties as the previously reported protein kinase C (PKC). Moreover, we have shown for the first time that this kinase or a kinase that coeluted from the column with PKC could be activated by a phorbol ester, PMA, in a phospholipid-free system, i.e. in the absence of any cofactor of PKC. These findings emphasize the need for caution in the interpretation of experimental results obtained when using phorbol esters to probe for a role of PKC in many regulatory processes.


Assuntos
Aparelho Lacrimal/enzimologia , Fosfolipídeos/metabolismo , Proteína Quinase C/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Animais , Cromatografia DEAE-Celulose , Ativação Enzimática , Aparelho Lacrimal/efeitos dos fármacos , Masculino , Dibutirato de 12,13-Forbol/farmacologia , Proteína Quinase C/isolamento & purificação , Ratos , Ratos Endogâmicos , Fosfolipases Tipo C/farmacologia
16.
Br J Pharmacol ; 102(1): 151-61, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1675142

RESUMO

1. Studies have been made of the contractile responses to the alpha-adrenoceptor agonists phenylephrine (Phen), cirazoline (Cir) or BHT-920 (BHT) in dog isolated saphenous vein (DSV) rings, using the antagonists yohimbine (Yoh), idazoxan (Idaz), prazosin (Praz), WB-4101 (WB) and nitrendipine or zero Ca2+ medium. 2. Contractile concentration-response curves to Phen or BHT were displaced to the right of controls by Yoh (0.01-3 microM) with mean apparent antagonist dissociation constants (pKBs) of 7.9 and 8.6 respectively. Yoh did not show simple competitive antagonism against either agonist, since the Schild plot slopes were significantly less than unity. Neither the antagonist affinity of Yoh against Phen, nor the slope of the Schild plot was modified in the presence of catecholamine uptake inhibitors, nor in the presence of alpha,beta-methylene ATP, which desensitizes P2-purinoceptors, suggesting that Phen does not release ATP, or noradrenaline to cause contraction in DSV. In the presence of Praz (0.3 microM) the antagonist potency of Yoh (mean pKB 7.4) against Phen was slightly decreased. Yoh had low potency against responses induced by Cir (pKB 6.3). 3. WB (0.001-1.0 microM) was a very potent antagonist of Phen-induced contractions, however, the biphasic Schild plot against Phen could be separated into two affinity sites, a high pKB of 9.3 (equivalent to that obtained using Cir as the agonist; pKB 9.6) and a lower affinity (pKB 8.6). WB showed an even lower antagonist affinity (pKB 7.4) against BHT-induced contractions, suggesting that these effects might be mediated by alpha 2A-adrenoceptors. Praz also appeared to identify two sites using Phen-induced contractions, a high pKB of 8.4 was equivalent to that obtained with Cir (pKB 8.2) and a lower affinity site (pKB 7.7; pA2 7.6; slope 1.1) at which Praz showed competitive antagonism. Higher concentrations of Praz were required to antagonize contractions to BHT (pKB 5.9). 4. Idaz was a weak partial agonist in this tissue with threshold contractile effects at concentrations in excess of 3 microM. Idaz (0.1-1 microM) competitively antagonized the contractile effects of BHT, but showed low antagonist affinity against Phen at these concentrations. 5. Contractions to Phen were slightly antagonized by nitrendipine (1 microM), with a 36% decrease in Emax. Contractions to Phen and Cir were also markedly attenuated in zero calcium medium (with EGTA), but maximum responses of 4.2 +/- 0.1 and 3.6 +/- 0.1 g, could be obtained with these agonists respectively. Only part of the contractile effects to Phen or Cir are therefore due to calcium influx (but L-type channels are not totally implicated), while the contractile effects of BHT were abolished in zero Ca2 + medium. Yoh (0.1 microm) retained its antagonist effects on Phen-induced responses in zero Ca2 + medium. 6. The formation of inositol phosphates (InsPs) in the presence of lithium (10mM) was measured after incubation of intact DSV strips with myo-2-[3H]-inositol. Phen (1-1OO0 microM) and Cir (O.O1-1O microm) induced concentration-dependent increases in total labelled InsP1_3, but BHT showed minimal InsP stimulation. InsPs were recovered after Phen (100,M) stimulation (10min) as labelled InsP1 (71%), InsP2 (25%) and InsP3 (4%). Phen (100 microM)-stimulated InsP1-3 formation was significantly antagonized by Praz (10nM), but was not fully inhibited even after Praz 1 microM. Yoh and Praz (0.1 and 1.0 microM) were equipotent inhibitors of this response, while Idaz (0.3 microM) showed no effects. 7. The receptors in DSV which are stimulated by Phen to cause contraction show characteristics of the alpha lA-adrenoceptor (high pM antagonist affinity for WB-4101 and extracellular calcium sensitivity) and the alpha lB-adrenoceptor (contraction in calcium-free medium, increase in InsP and low nm antagonist affinity of WB). The paradoxical results obtained with Yoh (potent antagonist effects on Phen-stimulated PI and pKB 7.9 on contraction) and Praz (low affinity competitive antagonist of Phen-induced contraction, pKB 7.7 and failure to inhibit completely the PI response at 1 microM), cannot fully exclude an alpha 2B-subtype characterization of these responses. These pharmacological differences suggest that the adrenoceptor involved in the contractile and in particular the second messenger effects of Phen in DSV is not typically an alpha lB-adrenoceptor.


Assuntos
Fosfatos de Inositol/biossíntese , Músculo Liso Vascular/fisiologia , Receptores Adrenérgicos alfa/fisiologia , Agonistas alfa-Adrenérgicos/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Cães , Feminino , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Fosfolipídeos/biossíntese , Receptores Adrenérgicos alfa/metabolismo , Veia Safena/efeitos dos fármacos , Veia Safena/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos
17.
Neuropeptides ; 13(3): 175-85, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2469032

RESUMO

In this study, we have compared the effects of Substance P (SP) and an SP deprived of the N-terminal tripeptide, SP(4-11), on phosphoinositide metabolism by measuring phosphoinositide breakdown, inositol phosphate production and inositol incorporation into phosphoinositides. This work shows that SP and SP(4-11) have similar effects on phosphatidylinositol-4.5 bisphosphate (PIP2) metabolism. In fact, SP(4-11), like SP, induces a rapid PIP2 breakdown. On the contrary, SP and SP(4-11) have different effects on phosphatidylinositol (PI) metabolism since SP induces a decrease of radioactivity in PI, whereas SP(4-11) does not. Both peptides stimulate [3H]-inositol mono-, bis- and trisphosphate (respectively IP1, IP2, IP3) production in a time and dose-dependent manner. The kinetic of IP3 production is directly correlated with the one of PIP2 breakdown. The time course of IP1 production after SP(4-11) shows a time delay, while the one after SP does not. Since SP evokes an IP1 production without any delay and a large decrease of radioactivity in PI (which cannot account for the small amount measured in IP1 accumulation) we suggest that SP could activate a PI specific phospholipase C (leading to a PI breakdown) and a phospholipase D. These activations would require the complete structure of SP while the classical PIP2 specific phospholipase C activation (which induces PIP2 breakdown) would only require the carboxamide part of the peptide. So the complete structure of SP would be necessary to have a complete response (stimulation of PIP2 and PI metabolism).


Assuntos
Glândula Parótida/metabolismo , Fosfatidilinositóis/metabolismo , Substância P/fisiologia , Animais , Ativação Enzimática , Técnicas In Vitro , Inositol/metabolismo , Fosfatos de Inositol/metabolismo , Masculino , Fragmentos de Peptídeos/farmacologia , Fosfolipase D/metabolismo , Ratos , Ratos Endogâmicos , Relação Estrutura-Atividade , Substância P/metabolismo , Substância P/farmacologia , Fosfolipases Tipo C/metabolismo
18.
Eur J Pharmacol ; 209(1-2): 95-100, 1991 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-1726089

RESUMO

Recent in vitro studies have shown that the dose-response curve of substance P on [3H]protein secretion from rat parotid glands is biphasic. Such a response could result either from the activation of tachykinin receptors or from the amphiphilic character of substance P, since it has previously been shown that the N-terminal part of substance P may play an important role in the activation of phosphoinositides in rat parotid glands. To investigate these possibilities, we studied the effects of selective NK1, NK2, NK3 receptor agonists and C-terminal fragments of substance P and neurokinin A on protein secretion from rat parotid lobules. The poor activity of NK2 (neurokinin A-(4-10) and [beta-Ala8]neurokinin A-(4-10)) as well as of NK3 ([MePhe7]neurokinin B) selective agonists allowed us to rule out a possible involvement of NK2 and NK3 receptors in the parotid gland secretory process. Conversely, the selective NK1 receptor agonist, [Sar9,Met(O2)11]substance P, reproduced the biphasic dose-response curve for [3H]protein secretion typical of native substance P. However, a biphasic response was not observed with peptides deprived of the N-terminal moiety of substance P, such as substance P-(4-11) or [AcArg6,Sar9,Met(O2)11] substance P-(6-11). Our data therefore indicate that the [3H]protein secretion obtained with substance P results from the activation of NK1 receptors. Moreover, our data suggest that the N-terminal tripeptide of substance P is also active, and could stimulate different phospholipases either by acting through a second functional site on the NK1 receptor or by directly activating G-proteins.


Assuntos
Glândula Parótida/metabolismo , Proteínas/metabolismo , Receptores de Neurotransmissores/fisiologia , Substância P/farmacologia , Sequência de Aminoácidos , Animais , Masculino , Dados de Sequência Molecular , Neurocinina A/farmacologia , Neurocinina B/farmacologia , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/ultraestrutura , Ratos , Ratos Endogâmicos , Receptores de Neurotransmissores/efeitos dos fármacos , Receptores de Taquicininas , Estimulação Química , Substância P/química
19.
Eur J Pharmacol ; 187(3): 357-67, 1990 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-1705891

RESUMO

Anti-idiotypic antibodies (anti-Id) obtained in rabbits in response to immunization with polyclonal anti-substance P antibodies (anti-SP) were shown to bind specifically and with high affinity to membranes from rat parotid gland cells. Whereas substance P (SP) was unable to displace anti-Id from membrane binding sites, anti-Id partly inhibited the binding of radiolabelled substance P. Like substance P, anti-Id were able to trigger protein secretion by parotid cells i.e. to behave as physiological agonists of the neuropeptide. Under our experimental conditions, the biological effects of both ligands appear to be additive. Unlike substance P, however, anti-Id did not potentiate the secretory response induced by a beta-adrenoceptor agonist. Taken together, the present results might indicate that anti-Id interact with epitope(s) at or/and near the peptide-combining site on the substance P receptor. These data demonstrate further the possibility of raising pharmacologically active anti-receptor antibodies through the immunological anti-idiotypic approach.


Assuntos
Anticorpos Anti-Idiotípicos/metabolismo , Glândula Parótida/metabolismo , Substância P/imunologia , Animais , Anticorpos Anti-Idiotípicos/isolamento & purificação , Anticorpos Monoclonais , AMP Cíclico/metabolismo , Imunoglobulinas/isolamento & purificação , Técnicas In Vitro , Radioisótopos do Iodo , Isoproterenol/farmacologia , Masculino , Glândula Parótida/imunologia , Ratos , Ratos Endogâmicos , Receptores da Neurocinina-1 , Receptores de Neurotransmissores/imunologia , Receptores de Neurotransmissores/metabolismo
20.
Eur Ann Allergy Clin Immunol ; 36(3): 101-3, 2004 Mar.
Artigo em Francês | MEDLINE | ID: mdl-15137481

RESUMO

We realized that it is essential that the patient who has an auto injector also has the direction sheet in its emergency bag. Patients, families but also young medical doctors' remarks and reflexions led us to create an explanatory didactic, precise, illustrated and practical direction sheet. The goals are to gather succinct information about the patient (personal contact information, medical history); remind emergency numbers (15 or 112) and the emergency treatment (antihistamine, broncholitor if necessary, epinephrine shots). It also indicates step by step how to use the auto injector (Anapen) and emphasizes the need for a medical supervision if the shot has been used. We present this direction sheet and the way to use it.


Assuntos
Anafilaxia/tratamento farmacológico , Antialérgicos/uso terapêutico , Rotulagem de Medicamentos , Epinefrina/administração & dosagem , Primeiros Socorros/instrumentação , Injeções Intramusculares/instrumentação , Educação de Pacientes como Assunto , Antialérgicos/administração & dosagem , Epinefrina/uso terapêutico , Controle de Formulários e Registros , Humanos , Autocuidado/instrumentação
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