RESUMEN
BACKGROUND: In patients with iron deficiency anemia, ferric carboxymaltose (FCM) and ferric derisomaltose (FDI) allow high-dose iron repletion. While FCM is reported to induce hypophosphatemia, the frequency of hypophosphatemia after an equivalent dosage of FDI had not been assessed prospectively. METHODS: In the prospective, single-center, double-blind HOMe aFers study, 26 women with iron deficiency anemia (hemoglobin < 12 g/dL plus either plasma ferritin ≤ 100 ng/mL or a plasma ferritin ≤ 300 ng/mL and transferrin saturation (TSAT) ≤ 30%) were randomized to a single intravenous infusion of 20 mg/kg body weight (up to a maximum of 1000 mg) FCM or FDI. The primary endpoint was the incidence of hypophosphatemia (plasma phosphorus levels < 2.0 mg/dL at day 1, day 7 ± 2, and/or day 35 ± 2 after the infusion). In order to investigate potential skeletal and cardiovascular implications, we assessed changes in other components of mineral and bone metabolism, left ventricular function, and arrhythmias. RESULTS: Hypophosphatemia occurred more frequently in women treated with FCM (9 out of 12 [75%]) than in those treated with FDI (1 out of 13 [8%]; p = 0.001). Within 24 h after iron supplementation, women in the FCM group had significant higher plasma intact FGF23 (p < 0.001) and lower plasma 1.25-dihydroxyvitamin D (p < 0.001). As an indicator of urinary phosphorus losses, urinary fractional phosphorus excretion was higher in the FCM group (p = 0.021 at day 7 ± 2 after iron supplementation). We did not observe differences in skeletal and cardiovascular markers, potentially because of the limited number of participants. CONCLUSIONS: While both FCM and FDI provide efficient iron repletion in participants with iron deficiency anemia, FCM induced hypophosphatemia more often than FDI. TRIAL REGISTRATION: Clinical Trials.gov NCT02905539. Registered on 8 September 2016. 2015-004808-36 (EudraCT Number) U1111-1176-4563 (WHO Universal Trial Number) DRKS00010766 (Deutsches Register Klinischer Studien).
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Anemia Ferropénica/complicaciones , Compuestos Férricos/efectos adversos , Hipofosfatemia/etiología , Hierro/sangre , Maltosa/análogos & derivados , Adulto , Anemia Ferropénica/sangre , Método Doble Ciego , Femenino , Factor-23 de Crecimiento de Fibroblastos , Humanos , Masculino , Maltosa/efectos adversos , Estudios ProspectivosRESUMEN
BACKGROUND: α-melanocyte-stimulating hormone (α-MSH) was shown to inhibit allergic airway inflammation and exert suppressive effects on human basophils. OBJECTIVE: This study aims to extend our current knowledge on the melanocortin 1 receptor (MC1R) expression in nasal tissue of patients with allergic rhinitis (AR) and functional effects of α-MSH in human basophils especially from patients with allergic rhinitis. METHODS: MC1R expression before and after nasal allergen provocation was studied in nasal mucosal tissue of AR patients and in a mouse model of allergic airway inflammation using immunofluorescence. In vitro regulation of the MC1R and CD203c surface expression on whole-blood basophils of patients with AR and controls was assessed with flow cytometry. Functional effects of α-MSH on isolated basophils were analysed regarding apoptosis with flow cytometry and chemotaxis using a Boyden chamber assay. RESULTS: We detected an accumulation of MC1R-positive basophils in nasal mucosa tissue of patients with AR 24 h after nasal allergen provocation. Such accumulation was not present in mucosa sections from healthy controls. In mice with allergic airway inflammation, we found a clear accumulation of MC1R-positive basophils in the nasal tissue compared to control mice. MC1R expression was inducible in AR patients and controls by stimulation with anti-IgE. α-MSH inhibited anti-IgE and grass pollen induced upregulation of CD203c, but had no effect on chemotaxis or apoptosis of basophils in vitro. CONCLUSIONS AND CLINICAL RELEVANCE: MC1R-positive basophils accumulate in the nasal mucosa of patients with AR after nasal allergen provocation. Since α-MSH suppresses proinflammatory effector functions in human basophils via the MC1R, it constitutes an interesting novel target for modulating the allergic inflammatory response.
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Receptor de Melanocortina Tipo 1/metabolismo , Rinitis Alérgica/inmunología , Rinitis Alérgica/metabolismo , Adulto , Alérgenos/inmunología , Animales , Basófilos/inmunología , Basófilos/metabolismo , Biopsia , Quimiotaxis/inmunología , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Humanos , Inmunoglobulina E/inmunología , Masculino , Ratones , Mucosa Nasal/inmunología , Mucosa Nasal/metabolismo , Mucosa Nasal/patología , Pruebas de Provocación Nasal , Hidrolasas Diéster Fosfóricas/metabolismo , Polen/inmunología , Pirofosfatasas/metabolismo , Receptor de Melanocortina Tipo 1/genética , Pruebas de Función Respiratoria , Rinitis Alérgica/diagnóstico , Rinitis Alérgica/genética , Pruebas Cutáneas , Adulto Joven , alfa-MSH/metabolismoRESUMEN
BACKGROUND: Growth retardation in paediatric end-stage renal disease (ESRD) has a serious impact on adult life. It is potentially treatable with recombinant growth hormone (rGH). In this study, we aimed to quantify the variation in rGH policies and actual provided care in these patients across Europe. METHODS: Renal registry representatives of 38 European countries received a structured questionnaire on rGH policy. Cross-sectional data on height and actual use of rGH on children with ESRD aged <18 years were retrieved from the ESPN/ERA-EDTA Registry. RESULTS: In 21 (75%) of 28 responding countries, rGH is reimbursed for children with ESRD. The specific conditions for reimbursement (minimum age, maximum age and chronic kidney disease stage) vary considerably. Mean height standard deviation scores (SDS) at renal replacement therapy (RRT) [95% confidence interval (CI)] were significantly higher in countries where rGH was reimbursed -1.80 (-2.06; -1.53) compared with countries in which it was not reimbursed [-2.34 (-2.49;-2.18), P < 0.001]. Comparison of the mean height SDS at onset of RRT and final height SDS yielded similar results. Among the 13 countries for which both data on actual rGH use between 2007 and 2011 and data from the questionnaire were available, 30.1% of dialysis and 42.3% of transplanted patients had a short stature, while only 24.1 and 7.6% of those short children used rGH, respectively. CONCLUSION: Reimbursement of rGH associates with a less compromised final stature of ESRD children. In many countries with full rGH reimbursement, the actual rGH prescription in growth-retarded ESRD children is low and obviously more determined by the doctor's and patients' attitude towards rGH therapy than by financial hurdles.
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Hormona de Crecimiento Humana/uso terapéutico , Fallo Renal Crónico/terapia , Pautas de la Práctica en Medicina/legislación & jurisprudencia , Medicamentos bajo Prescripción/administración & dosificación , Adolescente , Adulto , Estatura , Niño , Preescolar , Estudios Transversales , Europa (Continente) , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Sistema de Registros , Terapia de Reemplazo Renal/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
OBJECTIVES: To evaluate the efficacy, tolerability, and impact on quality of life (QoL) of bromelain tablets (500 FIP) in patients with chronic rhinosinusitis (CRS). METHODS: In this prospective, open-label observational pilot study, 12 patients suffering from CRS with (CRS+NP) or without (CRS-NP) nasal polyps who had undergone prior sinus surgery were treated with bromelain tablets (500 FIP) for three months. Efficacy was evaluated using symptom scores (Total Symptom Scores: TSS); a Total Rhinoscopy Score (TRS) was also determined. QoL was assessed by using the German, adapted version of the Sinonasal Outcome Test 20 (SNOT-20 GAV). RESULTS: Treatment with bromelain tablets (500 FIP) improved TSS, TRS and SNOT-20 GAV on average. This treatment was found to be more effective, however, for CRS-NP than for CRS+NP. The average intake was six tablets, equivalent to a daily dosage of 3000 FIP. No adverse events were observed. CONCLUSION: Preliminary results indicate good tolerability, symptom control, and improvement in QoL for the treatment of CRS using bromelain tablets (500 FIP).
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Antiinflamatorios no Esteroideos/uso terapéutico , Bromelaínas/uso terapéutico , Rinitis/tratamiento farmacológico , Sinusitis/tratamiento farmacológico , Adulto , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pólipos Nasales/complicaciones , Proyectos Piloto , Estudios Prospectivos , Calidad de Vida , Resultado del TratamientoRESUMEN
The aetiopathogenic mechanisms of vitiligo are still poorly understood, and this has held back progress in diagnosis and treatment. Up until now, treatment guidelines have existed at national levels, but no common European viewpoint has emerged. This guideline for the treatment of segmental and nonsegmental vitiligo has been developed by the members of the Vitiligo European Task Force and other colleagues. It summarizes evidence-based and expert-based recommendations (S1 level).
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Vitíligo/terapia , Administración Cutánea , Administración Oral , Corticoesteroides/administración & dosificación , Antioxidantes/uso terapéutico , Inhibidores de la Calcineurina , Lista de Verificación , Terapia Combinada , Fármacos Dermatológicos/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Fototerapia/métodos , Preparaciones para Aclaramiento de la Piel/uso terapéutico , Esteroides/administración & dosificación , Resultado del Tratamiento , Vitíligo/diagnósticoRESUMEN
Background The increasing prevalence of severe aortic valve defects correlates with the increase of life expectancy. For decades, surgical aortic valve replacement (AVR), under the use of extracorporeal circulation, has been the gold standard for treatment of severe aortic valve diseases. In Germany ~12,000 patients receive isolated aortic valve surgery per year. For some time, percutaneous balloon valvuloplasty has been used as a palliative therapeutic option for very few patients. Currently, alternatives for the established surgical procedures such as transcatheter aortic valve implantation (TAVI) have become available, but there are only limited data from randomized studies or low-volume registries concerning long-time outcome. In Germany, the implementation of this new technology into hospital care increased rapidly in the past few years. Therefore, the German Aortic Valve Registry (GARY) was founded in July 2010 including all available therapeutic options and providing data from a large quantity of patients.Methods The GARY is assembled as a complete survey for all invasive therapies in patients with relevant aortic valve diseases. It evaluates the new therapeutic options and compares them to surgical AVR. The model for data acquisition is based on three data sources: source I, the mandatory German database for external performance measurement; source II, a specific registry dataset; and source III, a follow-up data sheet (generated by phone interview). Various procedures will be compared concerning observed complications, mortality, and quality of life up to 5 years after the initial procedure. Furthermore, the registry will enable a compilation of evidence-based indication criteria and, in addition, also a comparison of all approved operative procedures, such as Ross or David procedures, and the use of different mechanical or biological aortic valve prostheses.Results Since the launch of data acquisition in July 2010, almost all institutions performing aortic valve procedures in Germany joined the registry. By now, 91 sites which perform TAVI in Germany participate and more than 15,000 datasets are already in the registry.Conclusion The implementation of new or innovative medical therapies needs supervision under the conditions of a well-structured scientific project. Up to now relevant data for implementation of TAVI and long-term results are missing. In contrast to randomized controlled trials, GARY is a prospective, controlled, 5-year observational multicenter registry, and a real world investigation with only one exclusion criterion, the absence of patients' written consent.
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Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Cateterismo Cardíaco , Implantación de Prótesis de Válvulas Cardíacas/métodos , Sistema de Registros , Anciano , Estenosis de la Válvula Aórtica/mortalidad , Estenosis de la Válvula Aórtica/psicología , Estudios de Seguimiento , Alemania/epidemiología , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia/tendencias , Resultado del Tratamiento , Adulto JovenRESUMEN
The most frequent cardiac arrhythmia and main cause for cardio-embolic stroke is atrial fibrillation. Prophylaxis for thrombembolic events is performed regarding individual risk of patients with either ASS or vitamin-K-antagonists. Efficacy and safety of oral anticoagulation is limited by a narrow therapeutical range as well as by inter- and intraindividual variability of INR-values due to genetic disposition, differences in alimentation, dosage errors, rare control of INR-levels and drug-interactions. New oral anticoagulants with different mechanisms of action may be a promising therapeutic option in future. This review addresses the new anticoagulants Apixaban, Rivaroxban and Dabigatranetexilat with the design and as available the results of the corresponding phase-III-trials in atrial fibrillation (ARISTOTLE, ROCKET-AF, RE-LY).
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Anticoagulantes/uso terapéutico , Fibrilación Atrial/complicaciones , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/prevención & control , Tromboembolia/prevención & control , Anticoagulantes/clasificación , Antitrombinas/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Azetidinas/uso terapéutico , Bencimidazoles/uso terapéutico , Bencilaminas/uso terapéutico , Ensayos Clínicos Fase III como Asunto , Dabigatrán , Inhibidores del Factor Xa , Fibrinolíticos/clasificación , Humanos , Morfolinas/uso terapéutico , Pirazoles/uso terapéutico , Piridinas/uso terapéutico , Piridonas/uso terapéutico , Rivaroxabán , Tiofenos/uso terapéuticoRESUMEN
This review article gives an overview on a number of novel clinical trials and registries in the field of cardiovascular medicine. Key presentations made at the 75th annual meeting of the German Cardiac Society, held in Mannheim, Germany, in April 2009 are reported. The data were presented by leading experts in the field with relevant positions in the trials and registries. These comprehensive summaries should provide the readers with the most recent data on diagnostic and therapeutic developments in cardiovascular medicine similar as previously reported (Rosenkranz et al. in Clin Res Cardiol 96:457-468, 9; Maier et al. in Clin Res Cardiol 97:356-363, 3).
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Enfermedades Cardiovasculares/terapia , Imagen por Resonancia Magnética , Ensayos Clínicos Controlados Aleatorios como Asunto , Sistema de Registros , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/patología , Ablación por Catéter , Desfibriladores Implantables , Stents Liberadores de Fármacos , Ácidos Grasos Omega-3/uso terapéutico , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Estudios Multicéntricos como Asunto , Medición de Riesgo/métodos , Sociedades Médicas , Células MadreRESUMEN
"Functional foods" supplemented with plant sterols are advertised and added to regular meals to reduce serum cholesterol concentrations. The effects of increased phytosterol levels on cardiovascular diseases, however, are not known. Findings in patients with sitosterolemia, data from epidemiological studies, and experimental data from animal studies suggest that plant sterols may potentially exert negative cardiovascular effects. Additional studies investigating relevant clinical endpoints are needed before a diet supplemented with plant sterols can be recommended in the prevention of cardiovascular diseases.
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Enfermedades Cardiovasculares/prevención & control , Suplementos Dietéticos , Fitosteroles/administración & dosificación , Animales , Anticolesterolemiantes/administración & dosificación , Anticolesterolemiantes/efectos adversos , Enfermedades Cardiovasculares/etiología , Colesterol/sangre , Humanos , Fitosteroles/efectos adversos , Factores de Riesgo , Sitoesteroles/sangreRESUMEN
HISTORY: A 40 year old patient was transferred to the intensive care unit five hours after the ingestion of 2.4 g of verapamil. ADMISSION FINDINGS: Clinical investigation and invasive monitoring showed signs of cardiogenic shock. THERAPY: Despite primary detoxification and administration of calcium and norepinephrine no adequate cardiovascular stabilization could be achieved. Only when the phosphodiesterase inhibitor enoximone was added, an increase in myocardial inotropy and a stable cardiovascular state was achieved which was also due to the vasoconstrictory effect of norepinephrine overcoming vasodilatation induced by enoximone. CONCLUSION: Detoxification, calcium supplementation and catecholamines are established therapeutic measures. An additional therapy with phosphodiesterase inhibitors is a promising step in conquering predominant heart failure and hypotension.
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Bloqueadores de los Canales de Calcio/envenenamiento , Enoximona/uso terapéutico , Norepinefrina/uso terapéutico , Inhibidores de Fosfodiesterasa/uso terapéutico , Simpatomiméticos/uso terapéutico , Verapamilo/envenenamiento , Adulto , Calcio/administración & dosificación , Quimioterapia Combinada , Humanos , Masculino , Intoxicación/complicaciones , Intoxicación/tratamiento farmacológico , Choque Cardiogénico/inducido químicamente , Choque Cardiogénico/tratamiento farmacológico , Vasoconstrictores/uso terapéutico , Vasodilatadores/envenenamientoAsunto(s)
Fibrilación Atrial/diagnóstico , Técnicas Electrofisiológicas Cardíacas/métodos , Corazón/fisiología , Factores de Edad , Fibrilación Atrial/clasificación , Fibrilación Atrial/epidemiología , Fibrilación Atrial/fisiopatología , Diagnóstico Diferencial , Ecocardiografía , Alemania/epidemiología , Humanos , Incidencia , Prevalencia , PronósticoAsunto(s)
Antiarrítmicos/uso terapéutico , Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/prevención & control , Fibrilación Atrial/terapia , Progresión de la Enfermedad , Cardioversión Eléctrica , Técnicas Electrofisiológicas Cardíacas/métodos , Humanos , Factores de Riesgo , Prevención Secundaria , Tromboembolia/prevención & control , Factores de Tiempo , Vitamina K/antagonistas & inhibidoresRESUMEN
Insomnia in patients with heart transplantation and cardiac disease is a common problem. Organic factors, immunodepressant medication (e.g. ciclosporine and steroids) and psychological factors may account for this symptom. The article reviews different hypnotic drugs and their value in the treatment of insomnia. For short-time treatment, medication with benzodiazepine hypnotics may be useful. If the problems of drug dependence and rebound insomnia are taken into consideration, treatment with non-benzodiazepine hypnotics offers more safety and comfort. If insomnia is part of a depressive syndrome, pharmacotherapeutical intervention with antidepressive sedative medication is required. With regard to cardiac disease, treatment with mirtazapine, nefazodone or trazodone should be preferred because of the chinidine-like effect of tricyclic antidepressants (TCA). Sedative neuroleptic medication (e.g. melperone) is commonly given to geriatric patients; nevertheless, patients with chronic insomnia may also benefit from this medication. The risks and benefits of hypnotic drugs are discussed especially in relation to pharmacological interaction (cytochrome system) and cardiac disease.
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Cardiopatías/complicaciones , Trasplante de Corazón , Hipnóticos y Sedantes/uso terapéutico , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Adulto , Anciano , Antidepresivos/uso terapéutico , Antipsicóticos/uso terapéutico , Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/tratamiento farmacológico , Trastorno Depresivo/tratamiento farmacológico , Interacciones Farmacológicas , Cardiopatías/tratamiento farmacológico , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/tratamiento farmacológico , Antagonistas de los Receptores Histamínicos/uso terapéutico , Humanos , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Hipnóticos y Sedantes/efectos adversos , Fitoterapia , Preparaciones de Plantas/uso terapéutico , Factores de Riesgo , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico , Trastornos del Inicio y del Mantenimiento del Sueño/etiología , Trastornos del Inicio y del Mantenimiento del Sueño/psicologíaRESUMEN
1. Long-term treatment with beta 2-adrenoceptor agonists can lead to a decreased therapeutic efficacy of bronchodilatation in patients with obstructive pulmonary disease. In order to examine whether or not this is due to beta-adrenoceptor desensitization, human bronchial muscle relaxation was studied in isolated bronchial rings after pretreatment with beta 2-adrenoceptor agonists. Additionally, the influence of pretreatment with dexamethasone on desensitization was studied. 2. The effect of beta 2-agonist incubation alone and after coincubation with dexamethasone on density and affinity of beta-adrenoceptors was investigated by radioligand binding experiments. 3. In human isolated bronchi, isoprenaline induces a time- and concentration-dependent beta-adrenoceptor desensitization as judged from maximal reduction in potency by a factor of 7 and reduction of 73 +/- 4% in efficacy of isoprenaline to relax human bronchial smooth muscle. 4. After an incubation period of 60 min with 100 mumol l-1 terbutaline, a significant decline in its relaxing efficacy (81 +/- 8%) and potency (by a factor 5.5) occurred. 5. Incubation with 30 mumol l-1 isoprenaline for 60 min did not impair the maximal effect of a subsequent aminophylline response but led to an increase in potency (factor 4.4). 6. Coincubation of dexamethasone with isoprenaline (120 min; 30 mumol l-1) preserved the effect of isoprenaline on relaxation (129 +/- 15%). 7. In radioligand binding experiments, pretreatment of lung tissue for 60 min with isoprenaline (30 mumol l-1) resulted in a decrease in beta-adrenoceptor binding sites (Bmax) to 64 +/- 1.6% (P < 0.05), while the antagonist affinity (KD) for [3H]-CGP-12177 remained unchanged. 8. In contrast, radioligand binding studies on lung tissue pretreated with either dexamethasone (30 mumol l-1) or isoprenaline (30 mumol l-1) plus dexamethasone (30 mumol l-1) for 120 min did not lead to a significant change of Bmax (160 +/- 22.1% vs 142.3 +/- 28.7%) or KD (5.0 nmol l-1 vs 3.5 nmol l-1) compared to the controls. 9. In conclusion, pretreatment of human bronchi with beta-adrenoceptor agonists leads to functional desensitization and, in lung tissue, to down-regulation of beta-adrenoceptors. This effect can be counteracted by additional administration of dexamethasone. Our model of desensitization has proved useful for the identification of mechanisms of beta-adrenoceptor desensitization and could be relevant for the evaluation of therapeutic strategies to counteract undesirable effects of long-term beta-adrenoceptor stimulation.
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Agonistas de Receptores Adrenérgicos beta 2 , Agonistas Adrenérgicos beta/farmacología , Bronquios/efectos de los fármacos , Dexametasona/farmacología , Pulmón/efectos de los fármacos , Receptores Adrenérgicos beta/efectos de los fármacos , Adulto , Anciano , Aminofilina/farmacología , Bronquios/fisiología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Técnicas In Vitro , Pulmón/fisiología , Masculino , Persona de Mediana Edad , Relajación Muscular/efectos de los fármacos , Terbutalina/farmacologíaRESUMEN
In the present study, we investigated serum and myocardial neuropeptide Y concentrations as measures of sympathetic activity as well as myocardial beta-adrenoceptors and beta-adrenoceptor-stimulated adenylyl cyclase activity in spontaneously hypertensive rats (SHR). SHR and control rats at 10 weeks of age were kept on oral treatment with captopril, nitrendipine, or both for 20 weeks. Treatment only slightly reduced but did not normalize blood pressure and cardiac hypertrophy in SHR. The elevated serum concentration of neuropeptide Y, the reduced number of beta-adrenoceptors, and the depressed beta-adrenoceptor-stimulated adenylyl cyclase activity were partly normalized compared with the values observed in control rats. We conclude that antihypertensive treatment, at doses that failed to normalize systolic pressure and to reverse cardiac hypertrophy completely, is able to reduce sympathetic activity in SHR, thereby resensitizing the depressed beta-adrenoceptor-adenylyl cyclase system.
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Cardiomegalia/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Neuropéptido Y/análisis , Receptores Adrenérgicos beta/análisis , Adenilil Ciclasas/metabolismo , Animales , Captopril/uso terapéutico , Cardiomegalia/fisiopatología , Hipertensión/fisiopatología , Masculino , Miocardio/química , Nitrendipino/uso terapéutico , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Ratas Wistar , Sistema Nervioso Simpático/fisiopatologíaRESUMEN
We investigated the effect of pharmacological treatment with captopril, nitrendipine, and captopril plus nitrendipine on myocardial heterologous adenylyl cyclase desensitization and the underlying postreceptor defects in spontaneously hypertensive rats (SHR). In myocardial membranes from SHR, stimulation of adenylyl cyclase with guanylylimido-diphosphate (P < .001) and forskolin (P < .05) was significantly reduced, whereas no difference with forskolin was obtained in the presence of manganese chloride. Reconstitution of Gs alpha into Gs alpha-deficient S49 cyc- mouse lymphoma cells revealed no difference between SHR and control rats. In contrast, pertussis toxin labeling of Gi alpha was significantly increased in SHR. The reduction of adenylyl cyclase in SHR was abolished after pertussis toxin treatment of membranes. Treatment with captopril, nitrendipine, or both reduced Gi alpha and increased guanylylimidodiphosphate-stimulated adenylyl cyclase activity in SHR. In summary, heterologous adenylyl cyclase desensitization due to an increase of Gi alpha but in the presence of an unchanged activity of Gs alpha or the catalyst occurs in SHR. This alteration, which could contribute to the progression of contractile dysfunction by producing adrenergic subsensitivity, is sensitive to pharmacological treatment most likely because of a reduction of sympathetic activity.
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Cardiomegalia/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Adenosina Difosfato Ribosa/metabolismo , Adenilil Ciclasas/metabolismo , Animales , Captopril/uso terapéutico , Cardiomegalia/metabolismo , Proteínas de Unión al GTP/análisis , Hipertensión/metabolismo , Masculino , Nitrendipino/uso terapéutico , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKYRESUMEN
A transgenic rat line, TGR(mREN2)27, was established by introducing the murine Ren-2 gene into the genome of rats by microinjection techniques. These rats exhibit severe hypertension, making them an interesting model in which to study the role of renin in the pathophysiology of hypertension. However, although the additional renin gene is the only genetic difference compared with control rats, the exact mechanism of hypertension in TGR(mREN2)27 rats is still unclear. It cannot be attributed to a stimulation of the endocrine renin-angiotensin system or to an overexpression of renin in the kidney, since plasma and kidney renin and renin gene expression in the kidney are low in these animals. Here we describe recent progress made toward elucidating mechanisms of hypertension in TGR(mREN2)27 rats. 1) TGR(mREN2)27 rats were bred to homozygosity. The development of high blood pressure in homozygous rats is accelerated compared with that of heterozygous rats. This is paralleled by a higher mortality rate in homozygous TGR(mREN2)27 rats. Blood pressure and mortality rate of homozygous transgenic rats were effectively reduced by 10 mg captopril per kilogram body weight. 2) Treatment of 8-week-old heterozygous TGR(mREN2)27 rats with 10 mg/kg body wt per day of the angiotensin II receptor antagonist DuP 753 for 4.5 weeks normalized blood pressure. After withdrawal of the drug, blood pressure increased rapidly, reaching control levels after 3 weeks. In another group of TGR(mREN2)27 rats treated with 0.5 mg/kg per day, there was no change in blood pressure. Plasma renin and plasma angiotensin II were significantly higher in the high-dose group compared with the low-dose group.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Animales Modificados Genéticamente/fisiología , Hipertensión/fisiopatología , Renina/fisiología , Corticoesteroides/fisiología , Antagonistas de Receptores de Angiotensina , Animales , Animales Modificados Genéticamente/sangre , Animales Modificados Genéticamente/genética , Compuestos de Bifenilo/farmacología , Presión Sanguínea/efectos de los fármacos , Expresión Génica , Hipertensión/sangre , Hipertensión/genética , Imidazoles/farmacología , Losartán , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas , Renina/genética , Sistema Renina-Angiotensina , Tetrazoles/farmacologíaRESUMEN
OBJECTIVE: beta 1 Adrenergic stimulation with the partial agonist xamoterol improves the systolic recovery of reperfused ("stunned") myocardium. The effects of this agent on isovolumetric relaxation and diastolic ventricular filling were evaluated. METHODS: In 15 open chest dogs, the distal left circumflex coronary artery was occluded for 15 min and then reperfused. Eight dogs served as placebo controls, and seven received xamoterol (100 micrograms.kg-1 intravenously) at 10 min reperfusion. Diastole was divided into an isovolumetric relaxation phase and a subsequent filling phase, and wall excursion velocities were calculated. RESULTS: In the control group isovolumetric wall thinning velocity in the reperfused myocardium recovered only slowly, from -5.67(SD 5.29) mm.s-1 at 10 min reperfusion to -4.84(6.35) mm.s-1 at 30 min reperfusion and 2.99(7.97) mm.s-1 at 8 h reperfusion. Xamoterol increased isovolumetric wall thinning velocity in the reperfused myocardium, from -7.78(6.25) mm.s-1 at 10 min reperfusion to 3.43(6.09) mm.s-1 at 30 min reperfusion, and 12.04(5.66) mm.s-1 at 8 h reperfusion, whereas wall thinning velocity during the filling phase was unaffected. At 8 h reperfusion the difference between the groups was still significant. When compared with the effects on systolic wall thickening velocity, the impairment of isovolumetric wall thinning velocity during occlusion and the improvement due to xamoterol were both more marked. These functional differences were not reflected by the two indices of global diastolic function, peak negative dP/dt and relaxation constant tau. CONCLUSIONS: beta 1 Adrenergic stimulation with xamoterol improves isovolumetric relaxation in reperfused myocardium more markedly than systolic contraction, but it has no direct effect during diastolic filling.
Asunto(s)
Agonistas Adrenérgicos beta/uso terapéutico , Contracción Miocárdica/efectos de los fármacos , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Xamoterol/uso terapéutico , Animales , Diástole/fisiología , Perros , Corazón/fisiopatología , Hemodinámica/efectos de los fármacos , Daño por Reperfusión Miocárdica/fisiopatología , Estimulación QuímicaRESUMEN
The present study was designed to elucidate whether or not the positive inotropic effects of isoprenaline, milrinone, and DPI 201-106 in myocardial tissue from various sources reveal reliable results for the failing human heart. Therefore, in vitro positive inotropic responses were studied in human papillary muscle strips from patients with moderate heart failure (NNYHA II-III), human atrial trabeculae (HAT), isolated papillary muscles from Wistar-Kyoto rats (WK), and from spontaneously hypertensive rats (SHR). Results were compared with the effects of the compounds in papillary muscle strips from patients with severe heart failure (NYHA IV). In NYHA IV, positive inotropic responses were smaller for isoprenaline and milrinone than in NYHA II-III. The response to DPI 201-106 was more pronounced. In HAT, the effects of isoprenaline and milrinone were greater than in NYHA IV. The positive inotropic effect of DPI 201-106 was similar. In SHR, only the positive inotropic effect of isoprenaline was smaller than in WK. The effects of DPI 201-106 and milrinone did not differ. These data show that inotropic responses in NYHA II-III, HAT, WK, and SHR differ from the severely failing myocardium. It is concluded that new positive inotropic agents should be screened in human myocardial tissue from patients with heart failure, as experimental results from other sources may be irrelevant in this respect.
Asunto(s)
Cardiotónicos/farmacología , Isoproterenol/farmacología , Contracción Miocárdica/efectos de los fármacos , Piperazinas/farmacología , Piridonas/farmacología , Animales , Función Atrial , Calcio/farmacología , Evaluación Preclínica de Medicamentos/métodos , Corazón/efectos de los fármacos , Corazón/fisiología , Corazón/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Humanos , Técnicas In Vitro , Masculino , Milrinona , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas , Ratas Endogámicas WKY , Valores de Referencia , Función VentricularRESUMEN
Psoriasis is a common, chronic skin disorder that is conservatively estimated to affect between 1% and 2% of the population in the United States, not including mild cases. Despite the fact that psoriasis is one of the more common skin conditions requiring medical attention, it is poorly understood by the general public. This lack of information or misinformation on the part of health care administrators and insurers can affect the medical treatment of psoriasis and concomitant reimbursement in a manner that may be inappropriate and/or inadvertently deleterious to the patient's health care. The Committee on Psoriasis of the American Academy of Dermatology has sought to address this void. The Committee on Psoriasis is comprised of several dermatologists from the major academic medical centers in the United States. The combined expertise of this group reflects decades of experience in research, diagnosis, and treatment of psoriasis, as well as other skin diseases. This group has approved the "White Paper on Hospitalization for Psoriasis Care" as a straightforward, accurate, and well-documented source of information on psoriasis and psoriasis care. The purpose of this document is to explore the relevant medical aspects of the disease, its treatment modalities and their associated risks, and the outcomes of care.