Feocromocitoma quístico gigante: reporte de un caso / Pheochromocytoma giant cystic: a case report

El feocromocitoma quístico gigante es tumor adrenal raro en el que predomina el curso asintomático; por lo que muchos de los casos no son diagnosticados hasta el momento de la cirugía. La simple movilización del tumor se asocia con el paso a la sangre de grandes cantidades de catecolaminas y a una elevada morbimortalidad.; por esta razón la cirugía per se y su manejo perioperatorio constituyen un enorme desafío. En este artículo se presenta el caso de un feocromocitoma gigante maligno (35 cm) que ocupaba todo el hemiabdomen derecho. Aun con el diagnóstico preoperatorio de feocromocitoma, el bloqueo farmacológico preoperatorio y las medidas intraoperatorias, el paciente falleció poco antes de que finalizara la cirugía.

The giant cystic pheochromocytoma is a rare adrenal tumor in the predominantly asymptomatic course; so many cases are not diagnosed until the time of surgery. The simple mobilization of the tumor is associated with the passage to the blood of large amounts of catecholamines and high morbidity and mortality. So the surgery itself and perioperative management are a huge challenge. This article describes the case of a malignant giant pheochromocytoma (35 cm) which occupied the entire right abdomen. Even with the preoperative diagnosis of pheochromocytoma, pharmacological blockade preoperative and intraoperative measures, the patient died shortly before the end of surgery.

Significance of intraprostatic architecture and regrowth velocity for considering discontinuation of dutasteride after combination therapy with an alpha blocker: A prospective, pilot study

PURPOSE: We conducted a prospective single-center study to evaluate the possibility of discontinuation of dutasteride after combination therapy with an alpha blocker for benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: We prospectively treated BPH patients with an alpha blocker and dutasteride (0.5 mg/d). Patients who had been treated with alpha blockers against BPH for more than 2 months were eligible, and 20 patients were included in the study. After 6 months of combination therapy, dutasteride was discontinued. Patients were followed for 12 months after cessation. Prostate volume, intraprostatic architecture determined by transrectal ultrasound, peak urinary flow rate, postvoid residual urine volume, and the serum prostate-specific antigen level were evaluated every 6 months, and the International Prostate Symptom Score and overactive bladder symptom score (OABSS) every 3 months. Patients were allowed to restart dutasteride during the follow-up period according to their desire. RESULTS: Twelve patients (12/20, 60%) restarted the combination therapy from 6 to 12 months into the follow-up period. For patients who restarted dutasteride, the prostate volume and OABSS had increased and worsened after discontinuation, respectively. A visible transition zone with a clear border on transrectal ultrasound at baseline and regrowth of the prostate after discontinuation of dutasteride were risk factors for restarting the therapy (Mann-Whitney U test: p=0.008, p=0.017). CONCLUSIONS: Prostatic enlargement after discontinuation of dutasteride differs among patients. Rapid regrowth of the prostate leads to deterioration of storage symptoms and a tendency to restart dutasteride. Baseline intraprostatic architecture may be a predictive factor for whether the patient is a good candidate for discontinuation.

Antagonistas serotoninérgico e noradrenérgico por via subaracnoidea aumentam a resposta álgica em ratos / Subarachnoid serotonergic and noradrenergic antagonists increase the pain response in rats

JUSTIFICATIVA E OBJETIVOS: Há evidências de que a passagem de informações nociceptivas pelo corno posterior da medula espinhal (CPME) seguindo para níveis rostrais do sistema nervoso central sofre profundas influências excitatórias e inibitórias. A presente pesquisa teve como objetivo comparar os efeitos da metissergida, da fentolamina e da fentolamina associada à metissergida, administrados por via subaracnoidea, sobre as fases I, intermediária e II do teste da formalina modificado em ratos. MÉTODO: Foram utilizados 28 ratos Wistar machos, distribuídos aleatoriamente em quatro grupos (n = 7) para receber solução salina (GC), fentolamina (GF), metissergida (GM) ou fentolamina associada à metissergida (GFM) por via subaracnoidea. A dor foi induzida pela administração de formalina na região dorsal da pata posterior direita. O teste foi dividido em três fases; fase I, intermediária e fase II. A análise estatística dos resultados foi realizada utilizando o programa SPSS (Statistical Package for Social Sciences), adotando o nível de significância de 5 por cento. RESULTADOS: Na fase intermediária, o número de elevações da pata foi significativamente maior nos grupos GF, GM e GFM quando comparados com o grupo GC. CONCLUSÕES: Os resultados sugerem a existência de efeito noradrenérgico e serotoninérgico no sistema inibitório descendente da dor aguda, com a possibilidade de emprego de agonistas serotoninérgicos e α1-adrenérgicos para controle da dor aguda.

BACKGROUND AND OBJECTIVES: There is evidence that the passage of nociceptive information through the posterior horn of the spinal cord (PHSC) on its way to rostral levels of the central nervous system undergoes profound excitatory and inhibitory influences. The objective of the present study was to compare the effects of the subarachnoid administration of methysergide, phentolamine, and phentolamine associated with methysergide on phases I, intermediate, and II of the modified phormaline test in rats. METHODS: Twenty-eight male Wistar rats distributed randomly in four groups (n = 7) to received subarachnoid saline solution (GC), phentolamine (GF), methysergide (GM), or phentolamine associated with methysergide (GFM). Pain was induced by the administration of phormaline in the dorsal region of the right hind paw. The test was divided in three phases: phase I, intermediate, and phase II. Statistical analysis of the results was performed using the software SPSS (Statistical Package for Social Sciences), adopting a level of significance of 5 percent. RESULTS: In the intermediate phase the number of paw elevations was significantly higher in GF, GM, and GFM groups when compared to the GC group. CONCLUSIONS: The results suggest the existence of a noradrenergic and serotonergic effect in the inhibitory descending system of acute pain, with the possibility of using serotonergic and α1-adrenergic antagonists to control acute pain.

JUSTIFICATIVA Y OBJETIVOS: Existen evidencias de que el paso de informaciones nociceptivas por el cuerno posterior de la médula espinal (CPME), y que continúa hacia niveles rostrales del sistema nervioso central, sufre profundas influencias excitatorias e inhibitorias. La presente investigación quiso comparar los efectos de la metisergida, de la fentolamina y de la fentolamina asociada a la metisergida, administrados por vía subaracnoidea, sobre las fases I, intermedia y II del test de la formalina modificado en ratones. MÉTODO: Fueron utilizados en el experimento, 28 ratones Wistar machos, distribuidos aleatoriamente en cuatro grupos (n = 7), para recibir una solución salina (GC), fentolamina (GF), metisergida (GM) o fentolamina asociada a la metisergida ((GFM). El dolor fue inducido por la administración de formalina en la región dorsal de la pata posterior derecha. El test fue dividido en tres fases: fase I, intermedia y fase II. El análisis estadístico de los resultados fue hecho utilizando el programa SPSS (Statistical Package for Social Sciences), [Paquete Estadístico para las Ciencias Sociales], adoptando el nivel de significancia de un 5 por ciento. RESULTADOS: En la fase intermedia, el número de elevaciones de la pata fue significativamente mayor en los grupos GF, GM y GFM cuando se comparó con el grupo GC. CONCLUSIONES: Los resultados nos sugieren la existencia de un efecto noradrenérgico y serotoninérgico en el sistema inhibitorio descendiente del dolor agudo, con la posibilidad del uso de agonistas serotoninérgicos y α1-adrenérgicos para el control del dolor agudo.

Impacts of the Quinazoline-Based Alpha1-Antagonist, Terazosin, and of the Sulfonamide Derivative, Tamsulosin, on Serum Prostate-Specific Antigen and Prostate Volume

The aim of this study was to compare the impacts of terazosin and tamsulosin, on prostate activity, i.e., serum prostate-specific antigen, total prostate volume (TPV), and transition zone volume (TZV). A total of 90 patients who presented with lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH), ranging in age from 52 to 83 yr (median 65 yr), were included in the study. Patients were given 0.2 mg tamsulosin, 2 mg terazosin, or 4 mg terazosin once daily for an average of 14 months (range, 6-56 months). Subjective (International Prostate Symptom Scores, I-PSS) and objective (maximal flow rate and post-void residual) parameters were assessed both at baseline and at treatment cessation. Serum prostatespecific antigen (PSA) levels were found to be unaffected by treatment (1.2 and 1.3 ng/mL). In total patients, multivariate analysis showed that baseline TPV was the only independent predictor of treatment-related TPV reduction. Moreover, baseline TPV > or =30 g was found to be associated with a higher likelihood of TPV reduction (odds ratio [OR], 3.939; 95% confidence interval [CI], 1.506-10.304; p=0.005), and a baseline TZV of > or =10 g was associated with a 7.1-times greater chance of TZV reduction (OR, 7.100; 95% CI, 2.428-20.763; p<0.001). The same model showed that patients on 2 mg terazosin had a 10.8-fold greater likelihood (OR, 10.770; 95% CI, 1.409-82.323; p=0.022) and that those on 4 mg terazosin had a 9.0-fold greater likelihood (OR, 9.001; 95% CI, 1.724-46.995; p=0.009) of a TZV reduction than those on 0.2 mg tamsulosin. In addition, symptoms improved regardless of prostate activity after taking alpha1-blockers. Our findings suggest that terazosin reduces TZV and demonstrate that the relief of symptoms associated with BPH may not be due to a prostate activity reduction induced by apoptosis in the prostate gland.

Effects of alpha-1 adrenergic receptor antagonist, terazosin, on cardiovascular functions in anaesthetised dogs.

Initially a dose-response curve of phenylephrine was constructed at dose strengths of 1-16 microg/kg in a cumulative manner. Phenylephrine caused a significant rise in the mean arterial pressure, left ventricular systolic pressure, left ventricular contractility, stroke volume and a significant decline in the heart rate. Terazosin was administered in three selected doses of 10, 100 and 300 microg/kg. Following each dose of terazosin, dose-response curve of phenylephrine was constructed. Terazosin, per se, decreased the basal mean arterial pressure, left ventricular systolic pressure, left ventricular contractility and stroke volume significantly in a dose dependent manner with an increase in the heart rate with no significant change in the cardiac output. The baroreflex sensitivity at all the three doses remained unchanged. In conclusion, the present findings support the view that terazosin reduces the blood pressure in a physiologically more favorable manner by maintaining the neural integrity of the cardiovascular system.

A double-blind, randomized, placebo-controlled study, to assess the efficacy of alfuzosin in the treatment of patients with benign prostatic hyperplasia / Um estudo duplo cego, randomizado e controlado com placebo para avaliar a eficácia da alfuzosina no tratamento de pacientes com hiperplasia prostática benigna

Introduçäo: Os alfa-bloqueadores säo hoje as drogas de escolha no tratamento clínico de pacientes com hiperplasia prostática benigna (HPB). Os autores apresentam os resultados de um estudo prospectivo, randomizado, duplo-cego, e controlado por placebo da alfuzosina no tratamento de pacientes com HPB. Material e métodos: 31 pacientes foram randomizados em dois grupos: alfa-bloqueador seletivo alfuzosina na dose de 5 mg duas vezes ao dia (n=16) ou placebo (n=15) por 12 semanas. Os pacientes foram selecionados de acordo com critérios de inclusäo e exclusäo que, de forma geral, incluiram pacientes com 50 anos de idade ou mais, escore internacional de sintomas prostáticos (EISP) de 12 pontos, índice de qualidade de vida (IQV) de 3 pontos ou mais, e fluxo urinário máximo (Fmáx) entre 5 e 15 ml/s. Resultados: Näo houve diferença na taxa de melhora do EISP (37 por cento versus 29 por cento, p=0,446) e IQV (15 por cento versus 21 por cento, p=0,446) entre o grupo alfuzosina e o grupo placebo. No entanto, embora marginalmente significante, o Fmáx mostrou uma melhora marcante após a alfuzosina quando comparado ao placebo (50 por cento versus 5,5 por cento, p=0,06). A incidência de efeitos colaterais foi similar em ambos os grupos, alfuzosina e placebo (43,8 por cento versus 40 por cento, respectivamente). Conclusöes: O alfa-bloqueador alfuzosina näo é uma panacéia e, em alguns pacientes, a melhora clínica ocorre principalmente devido ao efeito placebo, que neste estudo resultou em aproximadamente 30 por cento de melhora do EISP (p=0,001), 21 por cento de melhora do IQV (p=0,017) e um aumento do Fmáx ò50 por cento em 26,5 por cento dos pacientes. Entretanto, o alfa-bloqueador alfuzosina tem um papel importante na abordagem clínica da HPB, já que seu mecanismo de açäo alivia o componente dinâmico da obstruçäo prostática, como demonstrado pela melhora do Fmáx.

Disfunçäo erétil / Erectile dysfunction

Na introduçäo, os autores apresentam dados epidemiológicos da disfunçäo erétil (DE) e, em seguida, o diagnóstico clínico da DE de origem orgânica e psicogênica, bem como o diagnóstico laboratorial. O tratamento é subdividido em informaçöes gerais, medicamentos por via oral (sildenafil e análogos, ioimbina e fentolamina, apomorfina, trazodone e L-arginina), medicamentos por via uretral (alprostadil), farmacoterapia intracavernosa, bombas de vácuo e próteses penianas. Os autores concluem que existiu uma grande evoluçäo da fisiopatologia e do tratamento da DE e que esta doença é bastante comum, existindo soluçöes para restabelecer o bem-estar do paciente.(au)

Modulation of feeding and drinking behaviour by catecholamines injected into nucleus accumbens in rats.

Nucleus accumbens is proposed as one of the centers in the neural circuitry involved in the regulation of feeding and drinking behaviour in rats. Injection of dopamine and angiotensin-II into this nucleus has been documented to affect water and food intake in rats. Reports on the effect of intracerebral injection of catecholamines on feeding and drinking behaviour in animal models are conflicting. Therefore, in the present study the effect of adrenaline and noradrenaline injected into nucleus accumbens on food and water intake in rats was assessed. 24 h basal food and water intakes were recorded in Wistar rats and were found to be 12.3 +/- 0.46 g and 21.7 +/- 1.03 ml respectively. Stainless steel cannulae were implanted stereotaxically into the nucleus accumbens. Four different doses (0.1 microgram, 0.5 microgram, 1 microgram, and 2 micrograms) of adrenaline and noradrenaline were injected into the nucleus accumbens through the implanted cannulae in different group of animals and their 24 h food and water intakes were recorded following these injections. No change in food and water intake was observed following the administration of different doses of adrenaline. A significant increase in 24 h water intake reaching a maximum of 28.88 +/- 1.45 ml at 1 microgram dose, without change in food intake was observed following administration of different doses of noradrenaline. The noradrenaline-facilitated water intake was blocked when noradrenaline was injected following injection of phentolamine, an alpha-receptor blocker. The bilateral lesions of nucleus accumbens resulted in a significant and sustained inhibition of water intake (16.61 +/- 0.67 ml) without change in food intake. These observations suggest that noradrenaline facilitates water intake without affecting food intake when injected into the nucleus accumbens in rats and the dipsogenic effect of noradrenaline is mediated by alpha-receptors. Adrenaline does not affect these ingestive behaviours when injected into the nucleus accumbens in rats.

Effect of prazosin GITS, atenolol, nifedipine SR, and enalapril on ADP-induced platelet aggregation.

A randomized, observer-blind, parallel-group study was carried out to compare the effect of prazosin GITS, atenolol, nifedipine SR, and enalapril on platelet aggregation, measured at a time expected to coincide with trough plasma levels of these drugs. 24 patients (age-30 to 60 yrs) with uncomplicated mild to moderate hypertension who completed a placebo run-in phase successfully were recruited in this study. They were randomly allocated to one of the 4 treatments: prazosin GITS 2.5 mg OD (Group 1), atenolol 50 mg OD (Group II), nifedipine SR 20 mg BD (Group III), and enalapril 5 mg OD (Group IV). All the drugs were given for 7 days, and blood samples were collected at 0 hr on day 1 (pre-treatment) and day 8 (post-treatment). Based on the dose (incremental concentrations of ADP)--response (% maximum aggregation) curve obtained, 2.5 microM/L of ADP was used to compare % inhibition of platelet aggregation among the 4 groups. We found that prazosin GITS inhibited % maximum aggregation significantly (p = 0.02) at 2.5 microM/L of ADP. Such inhibitory effect was not seen in any of the other groups. The inhibition produced by prazosin GITS differed significantly from the action of the other 3 drugs (p < 0.05). This antiplatelet effect of prazosin GITS bears more clinical relevance in view of the fact that it was seen at a time which is expected to coincide with the trough plasma levels of prazosin.

Efecto del carvedilol sobre la fracción de eyección y capacidad de ejercicio en pacientes con insuficiencia cardíaca / Effect of carvedilol on left ventricular ejection fraction and exercise performance in patients with chronic heart failure

Se evaluó el uso del carvedilol en pacientes con insuficiencia cardíaca mediante un ensayo clínico a doble ciego, valorándose la fracción de eyección y la capacidad de ejercicio. Se incluyó a 33 pacientes, a 14 se les administró placebo y a 19 carvedilol. La fracción de eyección basal fue 26,2 por ciento y 22 por ciento (p< 0,11), el tiempo de ejercicio fue 9,5 minutos y 9 minutos (p< 0,73), para los grupos tratados con carvedilol y con placebo respectivamente. La fracción de eyección, al final del estudio, fue 34,5 por ciento y 24,5 por ciento para los pacientes tratados con carvedilol y placebo en cada caso (p< 0,03). El tiempo de ejrcicio aumentó significativamente, 13,8 minutos y 10,6 minutos (p< 0,02)

Hypotensive effect of intracerebroventricular injection of norepinephrine and its modulation by alpha and beta adrenergic blockers in conscious rabbits.

The present study was designed to investigate the role of central adrenoceptors in the hypotensive effect of intracerebroventricular (ICV) injection of norepinephrine (NE) in conscious rabbits. Experiments were carried out on 19 adult rabbits (oryctolagus cuniculus) of either sex. A dose-dependent hypotensive response to ICV injection of NE was observed with no significant change in heart rate. The hypotensive response of NE was blocked 74.2 +/- 0.7% by yohimbine (alpha-2 adrenergic blocker), and 25.0 +/- 0.5% by metoprolol (beta-1 adrenergic blocker). NE response was not affected either by prazosin or butoxamine (alpha-1 and beta-2 adrenergic blockers respectively). The results suggest that the dose-dependent hypotensive response of ICV administered NE is mediated through alpha-2 and beta-1 central adrenoceptors.