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BACKGROUND: Telemedicine became a relevant means to provide healthcare without face-to-face medical evaluation during the COVID-19 pandemic. AIM: To describe the effectiveness of telemedicine in vascular surgery. MATERIALS AND METHODS: Review of medical records of all vascular surgery consultations carried out in a clinical hospital between April and October 2020. The main outcome measured was the resolution of the reason for consultation. Secondary outcomes were the need to request laboratory tests or imaging, the need to evaluate the patient in person, and the need for referral to hospitalization or emergency service. RESULTS: One hundred-six new consultations and their follow-up (remotely or in person) were analyzed. A definitive diagnosis could be reached in 74% of consultations, treatment could be instituted or modified in 69% of them, and the reason for consultation could be resolved in 74% of cases. Laboratory and imaging tests were requested in 36 and 63% of consultations, respectively. Four percent of patients were referred to the emergency department or hospitalization. CONCLUSIONS: In the vast majority of consultations, it was possible to achieve a definitive diagnosis, prescribe a treatment and resolve the reason for consultation without the need for a face-to-face medical evaluation.
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COVID-19 , Telemedicina , Humanos , Pandemias , Derivación y Consulta , Procedimientos Quirúrgicos VascularesRESUMEN
A modified Cp*Ru complex, equipped with a maleimide group, was covalently attached to a cysteine of an engineered variant of Ferric hydroxamate uptake protein component: A (FhuA). This synthetic metalloprotein catalyzed the intermolecular alkene-alkyne coupling of 3-butenol with 5-hexynenitrile. When compared with the protein-free Cp*Ru catalyst, the biohybrid catalyst produced the linear product with higher regioselectivity.
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Delirium occurs commonly following major non-cardiac and cardiac surgery and is associated with: postoperative mortality; postoperative neurocognitive dysfunction; increased length of hospital stay; and major postoperative complications and morbidity. The aim of this study was to investigate the effect of peri-operative administration of dexmedetomidine on the incidence of postoperative delirium in non-cardiac and cardiac surgical patients. In this randomised, double-blind placebo-controlled trial we included 63 patients aged ≥ 60 years undergoing major open abdominal surgery or coronary artery bypass graft surgery with cardiopulmonary bypass. The primary outcome was the incidence of postoperative delirium, as screened for with the Confusion Assessment Method. Delirium assessment was performed twice daily until postoperative day 5, at the time of discharge from hospital or until postoperative day 14. We found that dexmedetomidine was associated with a reduced incidence of postoperative delirium within the first 5 postoperative days, 43.8% vs. 17.9%, p = 0.038. Severity of delirium, screened with the Intensive Care Delirium Screening Checklist, was comparable in both groups, with a mean maximum score of 1.54 vs. 1.68, p = 0.767. No patients in the dexmedetomidine group died while five (15.6%) patients in the placebo group died, p = 0.029. For patients aged ≥ 60 years undergoing major cardiac or non-cardiac surgery, we conclude that the peri-operative administration of dexmedetomidine is associated with a lower incidence of postoperative delirium.
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Dexmedetomidina/uso terapéutico , Delirio del Despertar/epidemiología , Delirio del Despertar/prevención & control , Hipnóticos y Sedantes/uso terapéutico , Atención Perioperativa/métodos , Procedimientos Quirúrgicos Operativos , Anciano , Berlin/epidemiología , Método Doble Ciego , Femenino , Humanos , Incidencia , Tiempo de Internación/estadística & datos numéricos , Masculino , Estudios ProspectivosRESUMEN
BACKGROUND: Thoracoabdominal aortic aneurysm (TAAA) is an infrequent disease and demands a highly specialized and experienced management. Open repair (OR) is the gold standard but it is associated with significant morbidity and mortality. Paraplegia and renal failure are the most important complications. AIM: To report our results with OR treatment of TAAA. MATERIAL AND METHODS: Descriptive study including all patients with TAAA operated electively and consecutively by OR between 1983 and 2019. Main outcomes are operative mortality, renal and neurological morbidity, and long-term survival. RESULTS: We report 45 operated patients aged 33 to 84 years, 74% males. Aneurysm extension according to Crawford classification was I in 18%, II in 18 %, III in 36% and IV in 29%. Operative mortality was 4%. The frequency of paraplegia or paraparesis at discharge was 9%. No patient was discharged on hemodialysis. Survival at 5 and 10 years were 60% and 40% respectively. CONCLUSIONS: OR of TAAA is a complex procedure. Our results show perioperative mortality rates comparable to highly experienced centers. Although being a major procedure, OR remains an alternative to treat this serious condition.
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Aneurisma de la Aorta Torácica , Implantación de Prótesis Vascular , Aneurisma de la Aorta Torácica/complicaciones , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodos , Femenino , Humanos , Masculino , Paraplejía/complicaciones , Paraplejía/cirugía , Complicaciones Posoperatorias , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
Giant cell arteritis is more common in women older than 60 years, is associated with systemic inflammation symptoms and mainly involves the aortic arch and cranial arteries, specially the temporal artery. Symptomatic lower extremity arterial stenosis or occlusion is uncommon and can lead to limb loss. We report a 73-year-old woman presenting with a one-month history of lower extremity intermittent claudication of sudden onset. She also complained of fever, malaise, headache and weight loss. A non-invasive vascular study showed moderate femoral popliteal occlusive disease, with and abnormal ankle-brachial index (0.68 and 0.83 on right and left sides, respectively). An angio-computed tomography showed thickening of the aortic wall and severe stenosis in both superficial femoral arteries. Steroidal treatment was started, and a temporal artery biopsy was performed confirming giant cell arteritis. Six weeks after steroid therapy the patient had a complete remission of symptoms. A serologic exacerbation was subsequently treated with a humanized monoclonal antibody against the interleukin-6 receptor Tocilizumab, obtaining long time remission.
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Arteritis de Células Gigantes , Anciano , Índice Tobillo Braquial , Arterias , Femenino , Arteritis de Células Gigantes/complicaciones , Arteritis de Células Gigantes/tratamiento farmacológico , Humanos , Isquemia/diagnóstico por imagen , Isquemia/etiología , Arterias TemporalesRESUMEN
BACKGROUND: Pelvic venous insufficiency may cause pelvic congestion syndrome that is characterized by chronic pelvic pain exacerbated by prolonged standing, sexual activity or menstrual cycle. It may be treated by embolizing the dysfunctional pelvic venous drainage and sometimes resecting vulvar, perineal and thigh varices. AIM: To assess the results of embolization of insufficient pelvic or ovarian veins on pelvic congestion syndrome. MATERIAL AND METHODS: Analysis of 17 female patients aged 32 to 53 years, who underwent subjected to a selective coil embolization of insufficient pelvic and/or ovarian veins through the jugular, basilic or cephalic veins. In the preoperative period, all patients had a lower extremity venous duplex pelvic ultrasound examination and some had an abdominal and pelvic CT angiogram. RESULTS: The technical success of the procedure was 100% and no complications were registered. During a 32 month follow up, no patient had symptoms of pelvic venous insufficiency or relapse of vulvar or thigh varices. CONCLUSIONS: Embolization of insufficient pelvic and ovarian veins is a safe and successful procedure for the treatment of pelvic venous insufficiency or vulvar varices.
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Embolización Terapéutica/métodos , Ovario/irrigación sanguínea , Dolor Pélvico/terapia , Pelvis/irrigación sanguínea , Várices/terapia , Adulto , Dolor Crónico , Femenino , Humanos , Persona de Mediana Edad , Ovario/diagnóstico por imagen , Dolor Pélvico/diagnóstico por imagen , Pelvis/diagnóstico por imagen , Flebografía/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Síndrome , Resultado del Tratamiento , Várices/diagnóstico por imagenRESUMEN
An (η5-cyclopentadienyl)cobalt(i) complex was covalently incorporated into an engineered variant of the transmembrane protein ferric hydroxamate uptake protein component: A, FhuA ΔCVFtev, using a thiol-ene reaction. A CD spectrum shows the structural integrity of the biohybrid catalyst. MALDI-TOF of the segment containing the anchoring site for the cobalt complex Cys545 confirmed successful conjugation. This biohybrid catalyst catalyzed the cyclotrimerization of phenylacetylene to give a mixture of regioisomeric 1,2,4- and 1,3,5-triphenylbenzene in aqueous medium.
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Acetileno/análogos & derivados , Proteínas de la Membrana Bacteriana Externa/química , Cobalto/química , Complejos de Coordinación/química , Proteínas de Escherichia coli/química , Escherichia coli/química , Acetileno/química , Acetileno/metabolismo , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/metabolismo , Catálisis , Ciclización , Dimerización , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Compuestos Férricos/metabolismo , Ácidos Hidroxámicos/metabolismo , Modelos Moleculares , Ingeniería de ProteínasRESUMEN
The feasibility of de novo everolimus without calcineurin inhibitor (CNI) therapy following liver transplantation was assessed in a multicenter, prospective, open-label trial. Liver transplant patients were randomized at 4 weeks to start everolimus and discontinue CNI, or continue their current CNI-based regimen. The primary endpoint was adjusted estimated GFR (eGFR; Cockcroft-Gault) at month 11 post randomization. A 24-month extension phase followed 81/114 (71.1%) of eligible patients to month 35 post randomization. The adjusted mean eGFR benefit from randomization to month 35 was 10.1 mL/min (95% confidence interval [CI] -1.3, 21.5 mL/min, p = 0.082) in favor of CNI-free versus CNI using Cockcroft-Gault, 9.4 mL/min/1.73 m(2) (95% CI -0.4, 18.9, p = 0.053) with Modification of Diet in Renal Disease (four-variable) and 9.5 mL/min/1.73 m(2) (95% CI -1.1, 17.9, p = 0.028) using Nankivell. The difference in favor of the CNI-free regimen increased gradually over time due to a small progressive decline in eGFR in the CNI cohort despite a reduction in CNI exposure. Biopsy-proven acute rejection, graft loss and death were similar between groups. Adverse events led to study drug discontinuation in five CNI-free patients and five CNI patients (12.2% vs. 12.5%, p = 1.000) during the extension phase. Everolimus-based CNI-free immunosuppression is feasible following liver transplantation and patients benefit from sustained preservation of renal function versus patients on CNI for at least 3 years.
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Inhibidores de la Calcineurina , Ciclosporina/administración & dosificación , Rechazo de Injerto/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Hepatopatías/cirugía , Trasplante de Hígado , Sirolimus/análogos & derivados , Adolescente , Adulto , Anciano , Ciclosporina/efectos adversos , Everolimus , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Rechazo de Injerto/etiología , Supervivencia de Injerto/efectos de los fármacos , Humanos , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Sirolimus/administración & dosificación , Factores de Tiempo , Privación de Tratamiento , Adulto JovenRESUMEN
Esophageal squamous cell carcinoma can spread locally to neighboring organs in the mediastinum. When it invades the aorta, the patient may develop an aorto esophageal fistula (AEF), complication that carries a high mortality rate. We report a 62-year-old male with stage IV esophageal carcinoma who, after chemo radiation treatment, developed an AEF. He was successfully treated with the use of an aortic endograft. The patient died 13 months later due to progression of his cancer, without evidence of sepsis or new bleeding episodes.
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Enfermedades de la Aorta/etiología , Carcinoma de Células Escamosas/complicaciones , Fístula Esofágica/etiología , Neoplasias Esofágicas/complicaciones , Fístula Vascular/etiología , Enfermedades de la Aorta/cirugía , Procedimientos Endovasculares , Fístula Esofágica/cirugía , Resultado Fatal , Humanos , Masculino , Persona de Mediana Edad , Fístula Vascular/cirugíaRESUMEN
A case of a patient with a recurrent dedifferentiated retroperitoneal liposarcoma with extensive invasion of the thoraco-abdominal wall including the skin, requiring reconstructive surgery after debulking of the tumor is reported.
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Pared Abdominal/cirugía , Liposarcoma/cirugía , Procedimientos de Cirugía Plástica/métodos , Neoplasias Retroperitoneales/cirugía , Pared Torácica/cirugía , Anciano , Colgajos Tisulares Libres , Humanos , MasculinoRESUMEN
BACKGROUND: In hymenoptera-venom allergy, sera of up to 60% of patients show in vitro reactivity to honeybee venom (HBV) and yellow jacket venom (YJV). This phenomenon is mainly caused by specific IgE (sIgE) against cross-reactive carbohydrate determinants (CCD). Whether or not these antibodies can induce clinical symptoms is a longstanding debate. OBJECTIVE: The aim of this study was to investigate the biological activity of CCD-sIgE and the suitability of the basophil activation test (BAT) in hymenoptera venom-allergic patients having CCD-sIgE. METHODS: The biological activity of CCD-sIgE was analysed by application of native and CCD-depleted YJV and HBV in BAT with the blood of 62 hymenoptera venom-allergic patients and 16 non-allergic controls. According to results of intracutaneous skin tests (IC) with YJV and HBV and the existence of CCD-sIgE, patients were classified into six subgroups. RESULTS: In patients with mono-positive IC and CCD-sIgE, and thus double-positive sIgE, BAT with native venoms was also double positive in up to 67% of the patients. In contrast, BAT with CCD-depleted venoms was positive only with the IC-positive venom. However, activation of basophils with the IC-negative venom was significantly lower compared with the IC-positive one. In IC mono-positive patients without CCD-sIgE, BAT was mono-positive with the IC-positive venom in the native and in the CCD-depleted form. CCD-positive patients with double-positive IC were a heterogeneous group, with the majority of CCD-positive patients also being double positive with the native forms of both venoms but mono-positive with the CCD-depleted ones. CONCLUSIONS: In vitro BAT clearly demonstrates biological activity of CCD-sIgE. However, because most of the patients showed a mono-positive IC and activation of basophils with the IC-negative venom was significantly lower compared with the IC-positive one, the present data suggest that CCD-sIgE is clinically irrelevant in these patients.
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Alérgenos/inmunología , Basófilos/inmunología , Venenos de Abeja/inmunología , Carbohidratos/inmunología , Hipersensibilidad/diagnóstico , Pruebas Inmunológicas/métodos , Venenos de Avispas/inmunología , Adolescente , Adulto , Anciano , Especificidad de Anticuerpos , Reacciones Cruzadas , Diagnóstico Diferencial , Femenino , Humanos , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Sensibilidad y EspecificidadRESUMEN
In this study we report the synthesis of a series of composite nanostructures comprising LDH and TiO2 phases. The materials characterization showed that the LDH crystallites are encapsulated inside the TiO2 matrix after the anatase seeds are deposited on MgxAl-LDHs. The structure in which LDH phase is embedded into anatase matrix is unique bringing important advantages to the photocatalytic performances of the nanocomposites. The photocatalytic activity of the prepared nanocomposites was tested on the degradation of the methylene blue (MB) in aqueous solution. The photocatalytic activities of the nanocomposites were compared with commercial TiO2 nanoparticles Degussa P25. The nanocomposites exhibited superior photocatalytic activity in basic environment because the negatively charged surface of TiO2 nanoparticles at high pH attracts the positively charged methylene blue species.
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Hidróxido de Aluminio/química , Colorantes/química , Hidróxido de Magnesio/química , Nanocompuestos/química , Titanio/química , Adsorción , Concentración de Iones de Hidrógeno , Azul de Metileno/química , Microscopía Electrónica de Transmisión , Procesos Fotoquímicos , Espectrometría Raman , Difracción de Rayos XRESUMEN
Introducción: Los aneurismas de la arteria carótida extracraneal (ACEC) son poco frecuentes en comparación con las lesiones oclusivas. Los ACEC son menos del 1% de todos los aneurismas arteriales y solo el 10% son considerados aneurismas verdaderos. Caso Clínico: Paciente femenina de 84 años, en excelentes condiciones generales, hipertensa e hiperlipidémica, neurológicamente asintomática, con hallazgo de aneurisma de carótida interna derecha en el contexto de una arteria elongada, estenosis moderada ostial y oclusión de arteria carótida interna contralateral. Se realiza resección de aneurisma con anastomosis término terminal, endarterectomía del ostium y angioplastía con parche. Su evolución fue favorable, manteniéndose asintomática y con la reconstrucción permeable a 6 meses de seguimiento en eco duplex. Discusión: La elección del manejo del ACEC va a depender de sus características morfológicas, en este caso la presencia de tortuosidad extrema de la arteria carótida interna dificultaba la posibilidad de manejo endovascular, pero facilitaba la resección del aneurisma con anastomosis primaria término terminal. Conclusión: La aneurismectomía y reconstrucción es una modalidad de manejo disponible para los ACEC.
Introduction: Extracranial carotid artery aneurysms (ECAA) are rare compared to occlusive disease, less than 1% of all arterial aneurysms and only 10% are considered true aneurysms. Clinical case: A 84-year-old female, active and in excellent general health, with a prior history significant only for hypertension and hyperlipidemia was referred for a right internal carotid artery aneurysm and elongation in the context of contralateral internal carotid artery occlusion. The patient denied neurologic symptoms. Resection of the aneurysm and end-to-end anastomosis, endarterectomy of the ostium and patch angioplasty was performed. The patient had an uneventful recovery, remaining asymptomatic and the reconstruction patent on duplex scan at 6 month follow up. Discussion: The choice of repair alternatives for EICA depend on its morphological characteristics. The presence of extreme tortuosity of the internal carotid artery in this case, on one hand make difficult to consider endovascular alternatives, but facilitates aneurysm resection and primary end-to-end anastomosis. Conclusion: Aneurysmectomy and arterial reconstruction is a treatment alternative for EICA repair.
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BACKGROUND: Telemedicine became a relevant means to provide healthcare without face-to-face medical evaluation during the COVID-19 pandemic. AIM: To describe the effectiveness of telemedicine in vascular surgery. Materials and Methods: Review of medical records of all vascular surgery consultations carried out in a clinical hospital between April and October 2020. The main outcome measured was the resolution of the reason for consultation. Secondary outcomes were the need to request laboratory tests or imaging, the need to evaluate the patient in person, and the need for referral to hospitalization or emergency service. RESULTS: One hundred-six new consultations and their follow-up (remotely or in person) were analyzed. A definitive diagnosis could be reached in 74% of consultations, treatment could be instituted or modified in 69% of them, and the reason for consultation could be resolved in 74% of cases. Laboratory and imaging tests were requested in 36 and 63% of consultations, respectively. Four percent of patients were referred to the emergency department or hospitalization. Conclusions: In the vast majority of consultations, it was possible to achieve a definitive diagnosis, prescribe a treatment and resolve the reason for consultation without the need for a face-to-face medical evaluation.
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Humanos , Telemedicina , COVID-19 , Derivación y Consulta , Procedimientos Quirúrgicos Vasculares , PandemiasRESUMEN
BACKGROUND: Thoracoabdominal aortic aneurysm (TAAA) is an infrequent disease and demands a highly specialized and experienced management. Open repair (OR) is the gold standard but it is associated with significant morbidity and mortality. Paraplegia and renal failure are the most important complications. AIM: To report our results with OR treatment of TAAA. MATERIAL AND METHODS: Descriptive study including all patients with TAAA operated electively and consecutively by OR between 1983 and 2019. Main outcomes are operative mortality, renal and neurological morbidity, and long-term survival. RESULTS: We report 45 operated patients aged 33 to 84 years, 74% males. Aneurysm extension according to Crawford classification was I in 18%, II in 18 %, III in 36% and IV in 29%. Operative mortality was 4%. The frequency of paraplegia or paraparesis at discharge was 9%. No patient was discharged on hemodialysis. Survival at 5 and 10 years were 60% and 40% respectively. CONCLUSIONS: OR of TAAA is a complex procedure. Our results show perioperative mortality rates comparable to highly experienced centers. Although being a major procedure, OR remains an alternative to treat this serious condition.
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Humanos , Masculino , Femenino , Aneurisma de la Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/complicaciones , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodos , Paraplejía/cirugía , Paraplejía/complicaciones , Complicaciones Posoperatorias , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
Giant cell arteritis is more common in women older than 60 years, is associated with systemic inflammation symptoms and mainly involves the aortic arch and cranial arteries, specially the temporal artery. Symptomatic lower extremity arterial stenosis or occlusion is uncommon and can lead to limb loss. We report a 73-year-old woman presenting with a one-month history of lower extremity intermittent claudication of sudden onset. She also complained of fever, malaise, headache and weight loss. A non-invasive vascular study showed moderate femoral popliteal occlusive disease, with and abnormal ankle-brachial index (0.68 and 0.83 on right and left sides, respectively). An angio-computed tomography showed thickening of the aortic wall and severe stenosis in both superficial femoral arteries. Steroidal treatment was started, and a temporal artery biopsy was performed confirming giant cell arteritis. Six weeks after steroid therapy the patient had a complete remission of symptoms. A serologic exacerbation was subsequently treated with a humanized monoclonal antibody against the interleukin-6 receptor Tocilizumab, obtaining long time remission.
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Anciano , Femenino , Humanos , Arteritis de Células Gigantes , Arterias , Arterias Temporales , Arteritis de Células Gigantes/complicaciones , Arteritis de Células Gigantes/tratamiento farmacológico , Índice Tobillo Braquial , Isquemia/etiología , Isquemia/diagnóstico por imagenRESUMEN
Recent structure determinations suggested a new binding site for a non-redox active metal ion in subunit I of cytochrome c oxidase both of mitochondrial and of bacterial origin. We analyzed the relevant metal composition of the bovine and the Paracoccus denitrificans enzyme and of bacterial site-directed mutants in several residues presumably liganding this ion. Unlike the mitochondrial enzyme where a low, substoichiometric content of Ca2+ was found, the bacterial wild-type (WT) oxidase showed a stoichiometry of one Ca per enzyme monomer. Mutants in Asp-477 (in immediate vicinity of this site) were clearly diminished in their Ca content and the isolated mutant enzyme revealed a spectral shift in the heme a visible absorption upon Ca addition, which was reversed by Na ions. This spectral behavior, largely comparable to that of the mitochondrial enzyme, was not observed for the bacterial WT oxidase. Further structure refinement revealed a tightly bound water molecule as an additional Ca2+ ligand.
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Calcio/metabolismo , Complejo IV de Transporte de Electrones/química , Complejo IV de Transporte de Electrones/metabolismo , Mutación , Paracoccus denitrificans/enzimología , Animales , Sitios de Unión , Bovinos , Cobre/metabolismo , Cristalografía por Rayos X , Complejo IV de Transporte de Electrones/genética , Hierro/metabolismo , Mitocondrias/enzimología , Conformación Proteica , Sodio/química , Sodio/metabolismo , Espectrometría por Rayos X , AguaRESUMEN
OBJECTIVES: Hypertension in humans and experimental animals is known to be associated with an increase in left ventricular myocardial mass. The development of cardiac hypertrophy is not caused by increased blood pressure alone; the autonomic nervous system may also play an important role. DESIGN: The functional responses to the beta-adrenoceptor agonists isoprenaline, dobutamine, salbutamol and terbutaline, and the alpha 1-adrenoceptor agonists methoxamine, cirazoline and phenylephrine were studied in isolated (Langendorff) hearts from spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto (WKY) controls. The results were compared with data from radioligand binding experiments. RESULTS: There was no significant difference in the increase of left ventricular pressure induced by all beta-adrenoceptor agonists studied in SHR and WKY rat hearts. Although there was no significant difference in the response to phenylephrine, the inotropic responses to cirazoline and methoxamine proved to be significantly weaker in hearts from SHR than in those from WKY rats. Binding experiments with 3H-prazosin revealed no differences in density or affinity for cardiac tissues from SHR and WKY rats. CONCLUSIONS: Long-standing hypertension leads to an impaired response of the isolated heart to alpha 1-adrenoceptor stimulation, without changes in alpha 1-receptor density or affinity. It seems likely that changes in postreceptor events are responsible for the impaired inotropic response to alpha 1-adrenoceptor agonists in hearts from SHR.
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Agonistas alfa-Adrenérgicos/farmacología , Agonistas Adrenérgicos beta/farmacología , Cardiomegalia/fisiopatología , Hipertensión/fisiopatología , Contracción Miocárdica/efectos de los fármacos , Animales , Cardiomegalia/etiología , Hipertensión/genética , Masculino , Ensayo de Unión Radioligante , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Receptores Adrenérgicos alfa/análisis , Estimulación Química , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
OBJECTIVE: To study the inotropic response to beta-adrenoceptor stimulation in isolated hypertrophied hearts from hypertensive rats. DESIGN AND METHODS: Cardiac hypertrophy was induced in Wistar rats by stenosing the abdominal aorta. Functional responses to isoprenaline, dobutamine, terbutaline and salbutamol were measured in paced (5 Hz), aortically stenosed hearts (18-20 and 32-34 weeks of age) and compared with those of sham-operated spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats. RESULTS: Following aortic stenosis, which was accompanied by less hypertension than that sustained by SHR, the Wistar rat hearts showed more pronounced cardiac hypertrophy. An initially equal inotropic response to the beta-adrenoceptor agonists (18-20 weeks) was reduced to 45% at 32-34 weeks in SHR but not in WKY rat hearts. The response to beta-adrenoceptor stimulation in the hypertrophied Wistar rat hearts was reduced at 18-20 weeks to 30% and at 32-34 weeks to 10% of controls, respectively. The response by all hypertrophied hearts to forskolin and N,2'-O-dibutyryladenosine 3':5' monophosphate was also diminished. CONCLUSIONS: The impaired contractile response to beta-adrenoceptor agonism is more clearly related to cardiac hypertrophy than to hypertension.