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1.
J Intern Med ; 288(1): 103-115, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32112487

RESUMO

OBJECTIVE: The goal of this study was to characterize a Swedish family with members affected by spinocerebellar ataxia 27 (SCA27), a rare autosomal dominant disease caused by mutations in fibroblast growth factor 14 (FGF14). Despite normal structural neuroimaging, psychiatric manifestations and intellectual disability are part of the SCA27 phenotype raising the need for functional neuroimaging. Here, we used clinical assessments, structural and functional neuroimaging to characterize these new SCA27 patients. Since one patient presents with a psychotic disorder, an exploratory study of markers of schizophrenia associated with GABAergic neurotransmission was performed in fgf14-/- mice, a preclinical model that replicates motor and learning deficits of SCA27. METHODS: A comprehensive characterization that included clinical assessments, cognitive tests, structural neuroimaging studies, brain metabolism with 18 F-fluorodeoxyglucose PET ([18F] FDG PET) and genetic analyses was performed. Brains of fgf14-/- mice were studied with immunohistochemistry. RESULTS: Nine patients had ataxia, and all affected patients harboured an interstitial deletion of chromosome 13q33.1 encompassing the entire FGF14 and integrin subunit beta like 1 (ITGBL1) genes. New features for SCA27 were identified: congenital onset, psychosis, attention deficit hyperactivity disorder and widespread hypometabolism that affected the medial prefrontal cortex (mPFC) in all patients. Hypometabolism in the PFC was far more pronounced in a SCA27 patient with psychosis. Reduced expression of VGAT was found in the mPFC of fgf14-/- mice. CONCLUSIONS: This is the second largest SCA27 family identified to date. We provide new clinical and preclinical evidence for a significant psychiatric component in SCA27, strengthening the hypothesis of FGF14 as an important modulator of psychiatric disease.


Assuntos
Encéfalo/diagnóstico por imagem , Linhagem , Córtex Pré-Frontal/metabolismo , Degenerações Espinocerebelares/genética , Adolescente , Adulto , Animais , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Deleção Cromossômica , Cromossomos Humanos Par 13 , Transtornos Cognitivos/genética , Fatores de Crescimento de Fibroblastos/genética , Fluordesoxiglucose F18 , Genótipo , Humanos , Imuno-Histoquímica , Integrina beta1/genética , Imageamento por Ressonância Magnética , Camundongos Knockout , Neuroimagem , Testes Neuropsicológicos , Fenótipo , Tomografia por Emissão de Pósitrons , Transtornos Psicóticos/complicações , Compostos Radiofarmacêuticos , Degenerações Espinocerebelares/diagnóstico por imagem , Suécia , Proteínas Vesiculares de Transporte de Aminoácidos Inibidores/metabolismo , Adulto Jovem
2.
AJNR Am J Neuroradiol ; 40(8): 1265-1273, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31248867

RESUMO

BACKGROUND AND PURPOSE: Brain gadolinium retention is consistently reported for linear gadolinium-based contrast agents, while the results for macrocyclics are contradictory and potential clinical manifestations remain controversial. Furthermore, most previous studies are based on conventional T1-weighted MR imaging. We therefore aimed to quantitatively investigate longitudinal and transversal relaxation in the brain in relation to previous gadolinium-based contrast agent administration and explore associations with disability in multiple sclerosis. MATERIALS AND METHODS: Eighty-five patients with MS and 21 healthy controls underwent longitudinal and transverse relaxation rate (R1 and R2) relaxometry. Patients were divided into linear, mixed, and macrocyclic groups based on previous gadolinium-based contrast agent administration. Neuropsychological testing was performed in 53 patients. The dentate nucleus, globus pallidus, caudate nucleus, and thalamus were manually segmented. Repeatability measures were also performed. RESULTS: The relaxometry was robust (2.0% scan-rescan difference) and detected higher R1 (dentate nucleus, globus pallidus, caudate nucleus, thalamus) and R2 (globus pallidus, caudate nucleus) in patients receiving linear gadolinium-based contrast agents compared with controls. The number of linear gadolinium-based contrast agent administrations was associated with higher R1 and R2 in all regions (except R2 in the thalamus). No similar differences and associations were found for the macrocyclic group. Higher relaxation was associated with lower information-processing speed (dentate nucleus, thalamus) and verbal fluency (caudate nucleus, thalamus). No associations were found with physical disability or fatigue. CONCLUSIONS: Previous linear, but not macrocyclic, gadolinium-based contrast agent administration is associated with higher relaxation rates in a dose-dependent manner. Higher relaxation in some regions is associated with cognitive impairment but not physical disability or fatigue in MS. The findings should be interpreted with care but encourage studies into gadolinium retention and cognition.


Assuntos
Encéfalo/diagnóstico por imagem , Meios de Contraste/farmacologia , Gadolínio DTPA/farmacologia , Esclerose Múltipla/diagnóstico por imagem , Neuroimagem/métodos , Adulto , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
3.
AJNR Am J Neuroradiol ; 39(11): 1995-2000, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30262646

RESUMO

BACKGROUND AND PURPOSE: Cortical lesions are common in multiple sclerosis and are included in the latest diagnostic criteria. The limited sensitivity of cortical MS lesions on conventional MR imaging can be improved by phase-sensitive inversion recovery. Synthetic MR imaging could provide phase-sensitive inversion recovery without additional scanning, but the use of synthetic phase-sensitive inversion recovery remains to be validated. We aimed to compare the ability and clinical value of detecting leukocortical lesions with conventional and synthetic phase-sensitive inversion recovery in MS. MATERIALS AND METHODS: Twenty-one patients with MS prospectively underwent conventional and synthetic phase-sensitive inversion recovery, 3D T1-weighted, and T2 FLAIR imaging. Two neuroradiologists independently performed blinded phase-sensitive inversion recovery lesion assessments; a consensus rating with all sequences was considered the criterion standard. Lesion volumes were segmented. All participants underwent standardized cognitive and physical examinations and Fatigue Severity Scale assessment. Results were analyzed with multiple linear regressions. RESULTS: Interrater and criterion standard agreement for leukocortical lesions was excellent for both conventional and synthetic phase-sensitive inversion recovery (intraclass correlation coefficient = 0.79-0.97). Leukocortical lesion volumes for both sequences were associated with lower information-processing speed (P ≤ .01) and verbal fluency (P ≤ .02). Both phase-sensitive inversion recovery sequences showed a positive effect on the association when combining volumes of leukocortical lesions and white matter lesions with information-processing speed (P ≤ .005) and verbal fluency (P ≤ .03). No associations were found between leukocortical lesion volumes and physical disability or fatigue. CONCLUSIONS: Synthetic and conventional phase-sensitive inversion recovery have a sensitivity similar to that of leukocortical MS lesions. The detected leukocortical lesions are associated with cognitive dysfunction and thus provide clinically relevant information, which encourages assessment of cortical MS involvement at conventional field strengths.


Assuntos
Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Neuroimagem/métodos , Adulto , Disfunção Cognitiva/etiologia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações
4.
J Thromb Haemost ; 13(2): 219-27, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25472531

RESUMO

BACKGROUND: Family history of venous thromboembolism (VTE) has been suggested to be more useful in risk assessment than thrombophilia testing. OBJECTIVES: We investigated established genetic susceptibility variants for association with VTE and evaluated a genetic risk score in isolation and combined with known trigger factors, including family history of VTE. PATIENTS/METHOD: A total of 18 single nucleotide polymorphisms (SNPs) selected from the literature were genotyped in 2835 women participating in a Swedish nationwide case-control study (the ThromboEmbolism Hormone Study [TEHS]). Association with VTE was assessed by odds ratios (ORs) with 95% confidence interval (CI) using logistic regression. Clinical and genetic predictors that contributed significantly to the fit of the logistic regression model were included in the prediction models. SNP-SNP interactions were investigated and incorporated into the models if found significant. Risk scores were evaluated by calculating the area under the receiver-operating characteristics curve (AUC). RESULTS: Seven SNPs (F5 rs6025, F2 rs1799963, ABO rs514659, FGG rs2066865, F11 rs2289252, PROC rs1799810 and KNG1 rs710446) with four SNP-SNP interactions contributed to the genetic risk score for VTE, with an AUC of 0.66 (95% CI, 0.64-0.68). After adding clinical risk factors, which included family history of VTE, the AUC reached 0.84 (95% CI, 0.82-0.85). The goodness of fit of the genetic and combined scores improved when significant SNP-SNP interaction terms were included. CONCLUSION: Prediction of VTE in high-risk individuals was more accurate when a combination of clinical and genetic predictors with SNP-SNP interactions was included in a risk score.


Assuntos
Polimorfismo de Nucleotídeo Único , Trombose Venosa/genética , Adulto , Área Sob a Curva , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Razão de Chances , Linhagem , Fenótipo , Valor Preditivo dos Testes , Curva ROC , Medição de Risco , Fatores de Risco , Fatores Sexuais , Suécia/epidemiologia , Trombose Venosa/diagnóstico , Trombose Venosa/epidemiologia
5.
J Assist Reprod Genet ; 18(12): 644-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11808845

RESUMO

PURPOSE: To study retrospectively the outcome of intracytoplasmatic sperm injection (ICSI) in women with endometriosis compared with women with no known female infertility factor. METHODS: All couples treated with ICSI because of male infertility plus verified endometriosis (n = 26) and all couples treated with ICSI because of male infertility only (n = 125) during the period January 1995 to June 1999 were included. Data were collected from patient files and ICSI protocols. RESULTS: The time to complete down regulation was significantly longer (p = 0.0108), the dose of FSH significantly higher (0.0247), the day for oocyte pickup significantly later (p = 0.0091), and the cleavage rate of oocytes significantly lower (p = 0.0011) in women with endometriosis compared with controls. There was no significant difference in implantation rate or pregnancy rate between the groups. CONCLUSIONS: Women with endometriosis presented significantly reduced follicular response and oocyte cleavage rate, two mechanisms that might be related to a disturbed oogenesis.


Assuntos
Endometriose/fisiopatologia , Fertilização in vitro , Oócitos/fisiologia , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas , Adulto , Endometriose/terapia , Feminino , Humanos , Infertilidade Feminina/terapia , Masculino , Oligospermia/terapia , Gravidez
6.
Regul Pept ; 81(1-3): 49-53, 1999 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-10395407

RESUMO

OBJECTIVE: Nedocromil sodium (nedocromil) improves the clinical condition of asthmatic subjects but its mechanism of action is not fully understood. This study aimed to determine whether nedocromil alters the ability of contractile and relaxant non-adrenergic, non-cholinergic neural (NANC) responses to stabilise tone by inhibiting or potentiating these responses in bronchial smooth muscle and, if so, whether the action is on a pre- or postjunctional level. RESULTS: Nedocromil attenuated contractile but not relaxant NANC responses (elicited by electric field stimulation) significantly (P < 0.05) in guinea pig main bronchi in vitro. However, the ability of NANC responses to stabilise tone (convergence effect) was not significantly impaired by nedocromil. Furthermore, nedocromil did not significantly shift the concentration response curve (-log EC50) to neurokinin A (NKA), the dominating contractile NANC transmitter, or alter the maximum response to NKA (P > 0.05). Submaximum or maximum contractile responses to histamine were not markedly affected by nedocromil (P > 0.05). CONCLUSIONS: Nedocromil exerts selective neural inhibition of the contractile but not of the relaxant NANC responses on a pre-junctional level in bronchial smooth muscle. Nedocromil does not, however, markedly impair the ability of NANC response to stabilise bronchial smooth muscle tone.


Assuntos
Antiasmáticos/farmacologia , Brônquios/efeitos dos fármacos , Brônquios/fisiologia , Contração Muscular/efeitos dos fármacos , Nedocromil/farmacologia , Animais , Testes de Provocação Brônquica , Feminino , Cobaias , Histamina , Técnicas In Vitro , Relaxamento Muscular/efeitos dos fármacos , Relaxamento Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Neurocinina A/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Receptores Adrenérgicos/efeitos dos fármacos , Receptores Colinérgicos/efeitos dos fármacos
7.
J Assist Reprod Genet ; 15(9): 530-4, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9822979

RESUMO

PURPOSE: The aim of this retrospective study was to compare the outcome of in vitro fertilization and embryo transfer in women with endometriosis and a control group with tubal-factor infertility. METHODS: Forty-eight patients with endometriosis underwent 65 cycles of in vitro fertilization and embryo transfer at Huddinge University Hospital. The matched control group with tubal-factor infertility consisted of 98 cycles in 98 patients. These groups were retrospectively analyzed regarding stimulation, fertilization, embryo development, implantation, and pregnancy outcome. RESULTS: The fertilization rate was significantly lower in women with endometriosis, but the cleavage, implantation, and pregnancy rates did not differ. CONCLUSIONS: Our results show that women with endometriosis have a lower fertilization rate compared with women with tubal-factor infertility. However, once the oocyte is fertilized, it seems that the preembryo has a normal chance of implantation, leading to similar pregnancy rates.


Assuntos
Endometriose/fisiopatologia , Fertilização in vitro , Infertilidade Feminina/fisiopatologia , Resultado da Gravidez , Adulto , Implantação do Embrião/fisiologia , Transferência Embrionária , Doenças das Tubas Uterinas/complicações , Doenças das Tubas Uterinas/fisiopatologia , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Masculino , Gravidez , Estudos Retrospectivos , Sêmen/fisiologia
8.
Br J Pharmacol ; 117(6): 1009-15, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8882590

RESUMO

1. Salmeterol is a potent, selective and long acting beta 2-adrenoceptor agonist. In vitro, salmeterol exerts 'reassertion' relaxation of airways smooth muscle. Reassertion relaxation refers to the capacity of salmeterol to cause repeated functional antagonism of induced contraction when airway smooth muscle is intermittently exposed to, then washed free from, beta-adrenoceptor antagonists such as sotalol. The mechanism(s) underlying reassertion relaxation are unknown but may relate to high affinity binding of the long aliphatic side chain of salmeterol to an accessory site, distinct from the agonist recognition site, in or near the beta 2-adrenoceptor (exosite binding hypothesis). 2. In order to test the exosite hypothesis, three pure analogues of salmeterol, each exactly preserving the molecular structure of the aliphatic side chain but with zero or low efficacy at the beta 2-adrenoceptor were synthesized. The effect of pre-incubating guinea-pig tracheal smooth muscle with these analogues on salmeterol-induced reassertion relaxation was determined. 3. Computer Assisted Molecular Modelling of these molecules revealed that each of them exactly preserved the low energy linear conformation of the aliphatic side chain of salmeterol. Measurement of lipophilicity (octanol:water partition coefficient; log P) and direct partition into synthetic membranes (membrane partition coefficient; Kpmem) showed that all compounds had high affinity for lipids and membranes. In particular the biophysical properties of CGP 59162 (log P 1.89, Kpmem 16500) were very similar to salmeterol (log P 1.73, Kpmem 16800). 4. Two of the analogues, CGP 54103 and D 2543 (1 microM), which are structural mimics of the side chain of salmeterol, differing slightly in their length, did not prevent either the initial relaxation induced by salmeterol (0.1 microM) or the reassertion relaxation; however, it was not possible to determine whether either of these molecules occupied the beta 2-adrenoceptor. 5. The third analogue, CGP 59162, which has the substituents on the active saligenin head group of salmeterol in transposed positions, itself exerted a weak beta 2-adrenoceptor-mediated relaxation antagonized by ICI 118551 (beta 2-selective antagonist) but not CGP 20712 (beta 1-selective antagonist) and, at higher concentrations CGP 59162 caused reassertion relaxation suggesting that it may occupy and activate the beta 2-adrenoceptor in a manner analogous to salmeterol. 6. CGP 59162, at concentrations up to ten fold molar excess, did not prevent or reduce salmeterol-induced reassertion relaxation. 7. In conclusion these data are not consistent with the existence of a distinct 'exosite' recognising the aliphatic side chain of salmeterol mediating reassertion.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Albuterol/análogos & derivados , Broncodilatadores/farmacologia , Músculo Liso/efeitos dos fármacos , Albuterol/farmacologia , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Cobaias , Técnicas In Vitro , Relaxamento Muscular , Propanolaminas/farmacologia , Xinafoato de Salmeterol , Relação Estrutura-Atividade , Traqueia/efeitos dos fármacos
9.
Pulm Pharmacol ; 8(6): 283-8, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8819183

RESUMO

The long-acting beta 2-agonist salmeterol has been shown in several in vitro studies to produce non-beta-mediated relaxant effects. The aim of the present study was to investigate whether these effects have any relevance in humans in vivo. Thirteen healthy individuals were studied in a randomized, double-blind, cross-over study on five separate days. The subjects were pre-treated orally with either propranolol 400 mg in order to block beta-adrenoceptor mediated effects or placebo. Two hours after drug intake, three increasing doses of salmeterol (25 + 50 + 100 micrograms), salbutamol (100 + 200 + 400 micrograms) or placebo were given from matched meter dose inhalers at 1-h intervals between doses. Specific airway conductance (sGAW) was measured in a body plethysmograph at the beginning of the experiment and 30 and 60 min after each inhaled dose of the beta-agonists. Salmeterol and salbutamol produced the same maximal increase in sGAW and had the same area under the dose-response curves. Pre-treatment with propranolol totally inhibited the effect of both drugs. In conclusion, salmeterol at clinically used doses did not produce any non-beta-mediated bronchodilating effect in normal individuals, measured as sGAW. Salmeterol and salbutamol showed the same efficacy but salmeterol was four times more potent than salbutamol.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Albuterol/análogos & derivados , Albuterol/farmacologia , Administração por Inalação , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Albuterol/antagonistas & inibidores , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Propranolol/farmacologia , Xinafoato de Salmeterol
10.
Br J Pharmacol ; 114(7): 1478-82, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7606351

RESUMO

1. In the present study, the inhibitory effects of the selective beta 2-adrenoceptor agonists, salmeterol, formoterol and salbutamol, have been investigated on contractions of ferret trachea induced both by endogenous and exogenous acetylcholine. The aim of the study was to evaluate quantitative and/or qualitative differences in response which may indicate both pre- and post-junctional sites of action. The non-selective beta-antagonist, sotalol, was used to estimate beta-adrenoceptor involvement. 2. Isometric tension was measured in ferret isolated tracheal strips. The inhibitory effects of the drugs were studied on tonic contractions induced by pre-junctional activation with electrical field stimulation (EFS) (2 Hz, 700 mA) or post-junctional activation with exogenous acetylcholine (ACh) (0.5 microM, about EC80), giving a similar degree of smooth muscle response. 3. Concentration-response experiments were performed with formoterol (0.3 nM-0.3 microM) and salmeterol and salbutamol (10 nM-10 microM). The experiments ended with the addition of sotalol (10 microM). 4. All three beta-agonists inhibited the contractions in a concentration-dependent manner. Salbutamol, formoterol and salmeterol inhibited the EFS-induced contractions by 66(8)%, 105(5)% and 103(8)% (mean(s.e. mean)) respectively. ACh-induced contractions were inhibited by 37(6)%, 72(11)% and 33(8)%. Theophylline (10 nM-3 mM) inhibited the contractions to the same degree. 5. beta-Adrenoceptor blockade by sotalol significantly antagonized the inhibitory effects of salbutamol and formoterol on both EFS- and ACh-induced contractions. The effect of salmeterol on ACh-induced contraction was also significantly antagonized, whereas the inhibition of EFS-induced contraction was virtually unaffected. 6. In conclusion, salbutamol, salmeterol and formoterol produced greater inhibitory effects in preparations contracted by EFS than in preparations contracted by exogenously-added ACh. In the case of formoterol and salbutamol, the effects on both levels are most probably due to beta-adrenoceptor stimulation, whereas for salmeterol the dominant pre-junctional effect is probably not mediated via beta-adrenoceptors. This non-beta-mediated effect could represent an additional relaxant mechanism for salmeterol.


Assuntos
Albuterol/análogos & derivados , Albuterol/farmacologia , Broncodilatadores/farmacologia , Etanolaminas/farmacologia , Traqueia/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Relação Dose-Resposta a Droga , Estimulação Elétrica , Furões , Fumarato de Formoterol , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Xinafoato de Salmeterol
11.
Thorax ; 48(5): 547-53, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8100652

RESUMO

BACKGROUND: Formoterol and salmeterol are new long acting beta 2 adrenoceptor agonists. The maximum relaxant effect, potency and functional antagonism against carbachol induced contraction for salmeterol, formoterol and salbutamol have been compared in the guinea pig isolated trachea. In addition, the possibility of inducing a non-beta adrenoceptor mediated relaxation by salmeterol was studied. METHODS: Concentration response experiments were conducted with isolated tracheal preparations (n = 4-6 in all experiments), precontracted by carbachol to cause either 40% (60 nmol/l), 80% (0.3 mumol/l) or 100% (3 mumol/l, supramaximal) of the maximum contraction. Each beta agonist was added cumulatively at each level of precontraction. Additional cumulative concentration response experiments were conducted for salmeterol alone at the highest level of precontraction, with and without beta blockade by sotalol (1 mmol/l). With the drug concentrations which produced the maximum response and the highest level of precontraction, the relaxation of formoterol (10 nmol/l) and salmeterol (1 mumol/l) was also compared non-cumulatively. Finally, with the corresponding drug concentrations and precontraction, the relaxant effect was compared for formoterol (10 nmol/l) in salmeterol relaxed airways with that of salmeterol (1 mumol/l) in formoterol relaxed airways. RESULTS: The increase in carbachol concentration from 60 nmol/l to 3 mumol/l induced a rightward shift in the mean (SE) concentration (log steps) causing 50% maximum relaxation for salmeterol (0.73 (0.17)), formoterol (0.85 (0.18)), and salbutamol (1.13 (0.11)). Significant differences in the maximum relaxant effect were shown at the highest level of precontraction only, with a remaining active tension of percentage precontraction of 27% (4%) for 1 mumol/l salbutamol and 35% (3%) for 10 nmol/l formoterol compared with 50% (2%) for 1 mumol/l salmeterol. The rank order of potency was: formoterol > salbutamol approximately salmeterol at all levels of precontraction (-log EC50: 9.32 (0.05) for formoterol, 7.82 (0.08) for salbutamol, and 7.50 (0.13) for salmeterol at 80% maximum precontraction). Beta blockade by sotalol (1 mmol/l) significantly inhibited the relaxation induced by salmeterol (1 mumol/l) (remaining active tension: 104% (1%) v 71% (11%) of precontraction) but not the relaxation induced by salmeterol (10 mumol/l) (remaining active tension: 75% (5%) v 71% (12%) of precontraction). In the non-cumulative experiments, formoterol displayed more relaxant effect than salmeterol (remaining active tension: 51% (6%) v 65% (6%) of precontraction). Finally, formoterol significantly relaxed salmeterol relaxed airways (relaxant effect: 22% (8%) of precontraction) whereas there was no significant response to salmeterol in formoterol relaxed airways (relaxant effect: 5% (12%) of precontraction). CONCLUSIONS: In the guinea pig isolated trachea, formoterol and salbutamol produce more relaxant effect than salmeterol, suggesting that salmeterol is a partial beta 2 agonist. Very high concentrations of salmeterol may induce non-beta adrenoceptor mediated relaxation. Formoterol is more potent than both salbutamol and salmeterol. There is no pronounced difference in the magnitude of antagonism against carbachol induced contractions between salmeterol, formoterol, and salbutamol.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Albuterol/análogos & derivados , Albuterol/farmacologia , Etanolaminas/farmacologia , Traqueia/efeitos dos fármacos , Animais , Carbacol/farmacologia , Relação Dose-Resposta a Droga , Feminino , Fumarato de Formoterol , Cobaias , Relaxamento Muscular/efeitos dos fármacos , Xinafoato de Salmeterol , Sotalol/farmacologia
12.
Allergy ; 47(4 Pt 2): 384-7, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1360770

RESUMO

Formoterol and salmeterol are 2 newly developed beta 2-adrenoceptor agonists for inhalation with prolonged duration of effect compared with currently available beta 2-agonists. The clinical duration of effect has been suggested to be correlated to a decreased washability in vitro, i.e. decreased effect due to continuous washing of the organ bath. In this study we compared the washability and the onset of the relaxatory effect of formoterol (0.01 microM), salmeterol (0.05 microM) and salbutamol (0.1 microM) in isolated guinea pig trachea contracted with carbachol (0.1 microM). We also evaluated a possible influence of the epithelium on onset of action and/or duration of effect. A significant relaxatory effect of formoterol and salmeterol remained after washing, whereas no effect of salbutamol remained. We also found a rapid onset of action for both salbutamol and formoterol, but a significantly slower onset for salmeterol. Both the washability and the onset of action were found to be independent of the presence of the epithelium.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Albuterol/análogos & derivados , Albuterol/farmacologia , Etanolaminas/farmacologia , Músculo Liso/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Agonistas Adrenérgicos beta/administração & dosagem , Albuterol/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Epitélio/efeitos dos fármacos , Etanolaminas/administração & dosagem , Feminino , Fumarato de Formoterol , Cobaias , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Músculo Liso/fisiologia , Xinafoato de Salmeterol
13.
Pharmacol Toxicol ; 71(1): 41-4, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1326108

RESUMO

We used frontally opened tracheal rings, contracted with 10 microM of histamine to produce beta-adrenoceptor tachyphylaxis by isoprenaline incubation and to evaluate whether theophylline can prevent this tachyphylaxis. Two concentration-response experiments with isoprenaline were performed in each ring. Between the concentration-response experiments the rings were incubated using four different treatments, isoprenaline (3 microM), theophylline (1 mM), theophylline + isoprenaline or vehicle for 60 min. Tachyphylaxis was evaluated as the difference in pD2 (-log EC50) during the first and second concentration-response experiment. Isoprenaline incubation produced a shift to the right of the concentration-response curve. The shift was small (approximately 0.2 log units) but significantly different from the control group. Theophylline failed to influence the process either alone or in combination with isoprenaline. In conclusion, beta-adrenoceptor tachyphylaxis after isoprenaline incubation in isolated guinea-pig trachea proved to be a very small effect and we observed no influence by theophylline.


Assuntos
Isoproterenol/farmacologia , Taquifilaxia , Teofilina/farmacologia , Traqueia/efeitos dos fármacos , Animais , Feminino , Cobaias , Contração Isométrica/efeitos dos fármacos , Receptores Adrenérgicos beta/metabolismo
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