Influence of antihypertensive drugs on aortic and coronary effects of Ang-(1-7) in pressure-overloaded rats

This study investigated the influence of antihypertensive drugs, such as angiotensin-converting enzyme inhibitors (ACEIs), AT1 receptor blockers (ARBs), voltage-gated L-type calcium channel blockers, and mineralocorticoid receptor antagonists (MRAs), on the effects of angiotensin-(1-7) [Ang-(1-7)] on aorta and coronary arteries from pressure-overloaded rats. Pressure overload was induced by abdominal aortic banding (AB). To evaluate the role of antihypertensive drugs on the effect of Ang-(1-7), AB male Wistar rats weighing 250–300 g were treated with vehicle or low doses (5 mg·kg-1·day-1, gavage) of losartan, captopril, amlodipine, or spironolactone. Isolated aortic rings and isolated perfused hearts under constant flow were used to evaluate the effect of Ang-(1-7) in thoracic aorta and coronary arteries, respectively. Ang-(1-7) induced a significant relaxation in the aorta of sham animals, but this effect was reduced in the aortas of AB rats. Chronic treatments with losartan, captopril or amlodipine, but not with spironolactone, restored the Ang-(1-7)-induced aorta relaxation in AB rats. The coronary vasodilatation evoked by Ang-(1-7) in sham rats was blunted in hypertrophic rats. Only the treatment with losartan restored the coronary vasodilatory effect of Ang-(1-7) in AB rat hearts. These data support a beneficial vascular effect of an association of Ang-(1-7) and some antihypertensive drugs. Thus, this association may have potential as a new therapeutic strategy for cardiovascular diseases.

Espironolactona aumenta los niveles circulantes de angiotensina-(1-9) y revierte el remodelado cardíaco en la hipertensión arterial experimental / Spironolactone increases circulating levels of angiotensin-(1-9) and reverts cardiac remodeling in experimental hypertension

Previamente hemos demostrado que la eficacia de enalapril, candesartán y de fasudil -inhibidor de la vía RhoA/ROCK,- en el tratamiento del remodelado cardíaco en la hipertensión (HTA) e infarto al miocardio está mediada por aumento en los niveles circulantes del péptido vasoactivo angiotensina [Ang]-(1-9). Sin embargo, no hay información disponible si el antagonista del receptor de mineralocorticoide, espironolactona (espiro) disminuye el remodelado cardíaco aumentando los niveles circulantes de Ang-(1-9). El objetivo de este trabajo fue determinar si espironolac-tona disminuye el remodelado cardíaco aumentando los niveles circulantes de Ang-(1-9) en la hipertensión arterial experimental. Métodos. Estudio comparativo de 3 grupos experimentales. Se utilizaron ratas Sprague Dawley macho (150 ± 10 grs) unifrectomizadas tratadas con desoxi-corticosterona (DOCA, 60mg/Kg 2 veces sem, im) por 6 semanas. Como controles (Sham) se usaron ratas unifrectomizadas. A partir de la 3° semana las ratas DOCA con HTA> 140 mmHg fueron randomizadas a recibir vehículo o espiro (100 mg/kg día, gavage) por 3 sem. Al finalizar el tratamiento se determinó la presión arterial sistólica (PAS), masa corporal, peso del corazón (PC) y masa cardíaca relativa al largo de la tibia (MCR, mg ventrículos/LT*100). El grado de hipertrofia car-diomiocitaria se determinó midiendo el área y perímetro de los cardiomiocitos y la fibrosis por el contenido de colágeno en cortes teñidos con rojo picrosirio. Resultados (promedio ± ES): Conclusión: Espironolactona disminuye la PAS y aumenta los niveles circulantes de Ang-(1-9). Este aumento en los niveles circulantes de Ang-(1-9) se asocia con una disminución significativa de la hipertrofia y la fibrosis cardiaca hipertensiva. Este nuevo efecto de espironolactona en los niveles circulantes de Ang-(1-9), - péptido vasoactivo de la vía paralela del sistema renina-angiotensina-aldosterona,- podría contribuir al efecto antihipertensivo y disminución del daño cardiaco en la hipertensión y remodelamiento cardiovascular y renal patológico. Estos hallazgos pueden tener relevancia terapéutica en términos que Ang-(1-9) podría disminuir el daño cardiovascular patológico.

We have previously demonstrated that the efficacy of enalapril, candesartan and fasudil,- RhoA / ROCK inhibitor-, in the treatment of cardiac remodeling in hypertension (HT) and myocardial infarction is mediated by an increase in circulating levels of the vasoactive peptide angiotensin (Ang) -(1-9). However, it is not known whether the mineralocorticoid receptor antagonist, spironolactone (spiro) decreases cardiac remodeling by increasing the circulating levels of Ang- (1-9). The aim of this study was to determine whether spironolactone decreases cardiac remodeling by increasing circulating levels of Ang-(1-9) in experimental hypertension. Methods. Comparative study of 3 experimental groups. Unifirectomized male Sprague Dawley rats (150 ± 10 grams) were treated with deoxycorticos-terone (DOCA, 60 mg / kg 2 times a week, im) for 6 weeks. Unifirectomized rats were used as controls (Sham). At 3rd week after surgery, DOCA rats with HTA> 140 mmHg were randomized to receive vehicle or spironolactone (Spiro, 100 mg / kg day, gavage) for 3 weeks. At the end of treatment, systolic blood pressure (SBP), body mass (BM), heart weight (HW) and relative cardiac mass to the tibia length (MCR, mg ventricles / LT * 100) were determined. The degree of cardiomyocyte hypertrophy was determined by measuring the area and perimeter of cardiomyocytes and fibrosis by collagen content in sections stained with picrosirius red. Results (mean ± ES): Conclusion: Spironolactone decreases systolic blood pressure and increases circulating levels of Ang-(1-9). This increase in circulating levels of Ang- (1-9) was associated with a significant decrease in hypertrophy and hypertensive cardiac fibrosis. This new effect of spironolactone on the circulating levels of Ang- (1-9) - vasoactive peptide of the parallel pathway of the re-nin-angiotensin-aldosterone system - could contribute to the antihypertensive effect and decrease of cardiac damage in HT and cardiovascular remodeling and renal disease. These findings may have therapeutic relevance supporting that Ang-(1-9) may decreases pathologic cardiovascular damage.

Experimental rat model of diabetic nephropathy: RAGE detection and effect of spironolactone monotherapy

The glycation process results in formation of advanced glycation end products [AGEs], which accumulate in different organs at an accelerated rate in diabetes, resulting in alteration of both structure and function. This effect is via the receptor for AGES [RAGE], which is a signaling receptor leading to profibrotic reactions. The renin angiotensin aldosterone system [RAAS] is activated in diabetic nephropathy [DN] and leads to more renal damage. This is inhibited by angiotensin converting enzyme inhibitors [ACEIs] and angiotensin receptor blockers [ARBs] and mineralocorticoid receptor blockers [MRBs]. To show the monotherapeutic effect of spironolactone in diabetic nephropathy and to detect RAGE. Diabetes was induced in rats by streptozotocin. Three weeks after,spironolactone [SPL] was given for 4 weeks. Then, control, diabetic and treated rats were sacrificed. The results of blood chemistry at the end of 4 weeks showed statistical increase in serum sodium, potassium and urea with no effect on serum creatinine or blood glucose. Kidney pathological injuries were attenuated by SPL also, RAGE deposition compared to the diabetics. The study showed RAGE deposition in the experimental DN and confirmed the beneficial effects of MRB in DN

Dissociação da resposta anti-hipertensiva e metabólica à losartana e espironolactona em ratos com síndrome metabólica experimental / Dissociation of antihypertensive and metabolic response to losartan and spironolactone in experimental rats with metabolic sindrome

INTRODUÇÃO: O tratamento da hipertensão arterial (HA) em indivíduos com síndrome metabólica (SM) é um desafio, uma vez que terapias não medicamentosas são de difícil implementação e o tratamento farmacológico ideal não está totalmente estabelecido. OBJETIVO: Avaliar o bloqueio do sistema renina angiotensina aldosterona (SRAA) na pressão arterial (PA), na função e na morfologia renais em modelo experimental de SM induzida por dieta hiperlipídica. MÉTODOS: Ratos Wistar receberam ração hiperlipídica a partir da quarta semana de vida, por 20 semanas. Os grupos tratados receberam Losartana ou Espironolactona a partir da oitava semana de vida. Avaliou-se semanalmente o peso corporal e a PA de cauda por pletismografia. Ao final do experimento, foram realizados testes de tolerância oral à glicose, perfil lipídico, clearance de creatinina, medida direta da PA, análise morfométrica renal. RESULTADOS: A administração de dieta hiperlipídica se associou ao desenvolvimento de SM, caracterizada por acúmulo central de gordura, hipertensão arterial, hiperglicemia e hipertrigliceridemia. Nesse modelo não foram observadas alterações da histomorfometria renal. O bloqueio do receptor AT1 da angiotensina II (Ang II) preveniu o desenvolvimento da HA. O bloqueio mineralocorticoide não apresentou eficácia anti-hipertensiva, porém, associou-se à redução da gordura abdominal. CONCLUSÃO: A dissociação da resposta anti-hipertensiva aos bloqueios dos receptores da Ang II e mineralocorticoide indica a participação da Ang II na gênese da HA associada à obesidade. A redução da obesidade central com a Espironolactona sugere a presença de efeito adipogênico mineralocorticoide.

INTRODUCTION: The treatment of arterial hypertension (AH) in patients with metabolic syndrome (MS) is a challenge, since non drug therapies are difficult to implement and optimal pharmacological treatment is not fully established. OBJECTIVE: To assess the blockade of the rennin angiotensin aldosterone system (RAAS) in blood pressure (BP) in renal function and morphology in an experimental model of MS induced by high fat diet. METHODS: Wistar rats were fed on high fat diet from the fourth week of life, for 20 weeks. The groups received Losartan or Spironolactone from the eighth week of life. We weekly evaluated the body weight and BP by tail plethysmography. At the end of the experiment oral glucose tolerance, lipid profile, creatinine clearance tests, and the direct measurement of BP were performed. A morphometric kidney analysis was performed. RESULTS: The administration of high-fat diet was associated with the development of MS, characterized by central fat accumulation, hypertension, hyperglycemia and hypertriglyceridemia. In this model there were no changes in renal histomorphometry. The blockade of angiotensin II (Ang II) receptor AT1 prevented the development of hypertension. The mineralocorticoid blockage did not have antihypertensive efficacy but was associated with reduction of abdominal fat. CONCLUSION: The dissociation of the antihypertensive response to the blockades of Ang II receptors and mineralocorticoid indicates the involvement of Ang II in the pathogenesis of hypertension associated with obesity. Reduction of central obesity with Spironolactone suggests the presence of mineralocorticoid adipogenic effect.

Efecto de la administración de espironolactona sobre la pérdida de podocitos y la progresión de la nefropatía diabética experimental / Effects of spironolactone administration on the podocytes loss and progression of experimental diabetic nephropathy

Objetivos. Evaluar el efecto de espironolactona (SPL) sobre la pérdida de los podocitos durante la progresión de la nefropatía diabética (ND) experimental. Materiales y métodos. Aleatoriamente un grupo de ratas macho Holtzman recibieron estreptozotocina (grupo diabético) o citrato buffer (grupo control). Las ratas diabéticas fueron tratadas con SPL (50 mg/kg/día). El área glomerular y la celularidad fueron evaluadas por métodos histomorfométricos. La lesión y pérdida de podocitos fue evaluada por la expresión de desmina y Wt-1, respectivamente. La expresión génica del TGF-β1 se evaluó mediante RT-PCR. Resultados. Los niveles de glucosa, el área glomerular, la expansión mesangial y el contenido de colágeno se incrementaron significativamente en las ratas diabéticas. La administración de SPL previno estos cambios sin modificar los niveles de glucosa. La inmunotinción para Wt-1 se redujo significativamente, mientras que la inmunotinción para desmina se incrementó drásticamente en las ratas diabéticas. El tratamiento con SPL previno el incremento de expresión de desmina y la pérdida de expresión de Wt-1. Asimismo, la administración de SPL previno el incremento de la expresión del mRNA del TGF-β1 en las ratas diabéticas. Conclusiones. El tratamiento con SPL, a través de efectos glucosa independientes, atenúa la perdida de podocitos y la progresión de los cambios morfológicos de la ND. Los presentes resultados sugieren que estos efectos son mediados, al menos en parte, por la inhibición de la la expresión del mRNA del TGF-β1.

Objectives. Evaluate the effect of spironolactone (SPL) on the loss of podocytes during the progression of experimental diabetic nephropathy (DN). Materials and methods. A group of male Holtzman rats randomly received streptozotocin (diabetic group) or a buffer citrate (control group). Diabetic rats were treated with SPL (50 mg/kg/day). The glomerular area and the cellularity were evaluated by histomorphometric methods. The injury and loss of podocytes was assessed by desmin expression and Wt-1, respectively. The gene expression of TGF-β1 was assessed by RT-PCR. Results. Glucose levels, the glomerular area, the mesangial expansion and collagen content increased significantly in diabetic rats. The administration of SPL prevented these changes without changing glucose levels. Immunostain for Wt-1 decreased significantly while immunostain for desmin increased dramatically in diabetic rats. Treatment with SPL prevented the increase of desmin expression and the loss of Wt-1 expression. Furthermore, the administration of SPL prevented the increase of TGF-β1 mRNA expression in diabetic rats. Conclusions. Treatment with SPL, through independent glucose effects, reduces the loss of podocytes and the progression of DN morphological changes. These results suggest that these effects are mediated, at least in part, by the inhibition of TGF-β1 mRNA expression.

Effect of aldosterone on the amplification of oncolytic vaccinia virus in human cancer lines / 대한간학회지

BACKGROUND/AIMS: JX-594 is an oncolytic virus derived from the Wyeth vaccinia strain that causes replication-dependent cytolysis and antitumor immunity. Starting with a cross-examination of clinical-trial samples from advanced hepatocellular carcinoma patients having high levels of aldosterone and virus amplification in JX-594 treatment, we investigated the association between virus amplification and aldosterone in human cancer cell lines. METHODS: Cell proliferation was determined by a cell-counting-kit-based colorimetric assay, and vaccinia virus quantitation was performed by quantitative polymerase chain reaction (qPCR) and a viral plaque assay. Also, the intracellular pH was measured using a pH-sensitive dye. RESULTS: Simultaneous treatment with JX-594 and aldosterone significantly increased viral replication in A2780, PC-3, and HepG2 cell lines, but not in U2OS cell lines. Furthermore, the aldosterone treatment time altered the JX-594 replication according to the cell line. The JX-594 replication peaked after 48 and 24 hours of treatment in PC-3 and HepG2 cells, respectively. qPCR showed that JX-594 entry across the plasma membrane was increased, however, the changes are not significant by the treatment. This was inhibited by treatment with spironolactone (an aldosterone-receptor inhibitor). JX-594 entry was significantly decreased by treatment with EIPA [5-(N-ethyl-N-isopropyl)amiloride; a Na+/H+-exchange inhibitor], but aldosterone significantly restored JX-594 entry even in the presence of EIPA. Intracellular alkalization was observed after aldosterone treatment but was acidified by EIPA treatment. CONCLUSIONS: Aldosterone stimulates JX-594 amplification via increased virus entry by affecting the H+ gradient.

Aldosterone Modulates Cell Proliferation and Apoptosis in the Neonatal Rat Heart

In the present study, we investigated whether and how the mineralocorticoid receptor antagonist spironolactone affects cardiac growth and development through apoptosis and cell proliferation in the neonatal rat heart. Newborn rat pups were treated with spironolactone (200 mg/kg/d) for 7 days. The cell proliferation was studied by PCNA immunostaining. The treatment with spironolactone decreased proliferating myocytes by 32% (P<0.05), and reduced myocytes apoptosis by 29% (P<0.05). Immunoblot and immunohistochemistry for the expression of p38, p53, clusterin, TGF-beta2, and extracellular signal-regulated kinase were performed. In the spironolactone group, p38, p53, clusterin, and TGF-beta2 protein expression was significantly decreased (P<0.05). These results indicate that aldosterone inhibition in the developing rat heart induces cardiac growth impairment by decreasing proliferation and apoptosis of myocytes.

Aldosterone receptor antagonists induce favorable cardiac remodeling in diastolic heart failure patients / Antagonistas de receptores de aldosterona inducen remodelación cardiaca favorable en pacientes con insuficiencia cardiaca diastólica

Background. Serum levels of aldosterone in heart failure are increased up to 20 times compared to normal subjects. After an acute myocardial infarction, aldosterone increases progressively as well as interstitial fibrosis and collagen synthesis from cardiac fibroblasts, forming a patchy heterogeneous interstitial collagen matrix that affects ventricular function. Even if angiotensine converting enzyme inhibitors (ACEI) or angiotensin II receptor antagonists (ARA) can reduce aldosterone levels early during treatment, they increase again after a 12 week treatment. The aim of this study was to evaluate the changes in structure and function of the left ventricle in symptomatic (NYHA I-III) diastolic heart failure patients receiving an aldosterone receptor antagonist. Methods. Twenty-eight subjects with diastolic heart failure, on BB, ACEI and/or ARA were randomized to receive spironolactone (group A) on a mean dose of 37.5 mg once a day (n =14, age 63.7 ± 21.6 years and body mass index, BMI 27.5 ± 9.4), or not (group B, n = 14, Age 64.8 ± 11.9, BMI 26.9 ± 4.7). All patients were followed-up for a mean of 13.79 ± 0.99 months. Results. Group A showed a 42.8% ischemic origin of heart failure, while in group B was 55% (p = 0.2). No other co-morbidities were significativelly different among both groups. Mean percentage of changes by echocardiogram was as follows: Interventricular septum (IVS) -12.2 ± 11% vs. 1.3 ± 15.2 (p = 0.03), pulmonary systolic artery pressure (PSAP was 0.99 ± 3.8% vs. 10.5 ± 9.1, p = 0.05). Other parameters did not show statistically significant differences. Conclusion. Aldosterone receptor antagonists reduce or avoid increasing of PSAP and inducing a favorable remodeling of the left ventricle, especially in the IVS in diastolic heart failure patients.

Antecedentes. En pacientes con insuficiencia cardiaca existen aumentos de aldosterona hasta 20 veces mayores que en sujetos control. Después de un infarto miocárdico la aldosterona aumenta progresivamente, así como la fibrosis intersticial y la síntesis de colágena por fibroblastos cardiacos, provocando parches intersticiales heterogéneos en la matriz de colágena que afecta la función ventricular. El tratamiento inicial con inhibidores de enzima convertidora de angiotensina (IECA) y/o antagonistas de receptores de angiotensina II (ARA) puede reducir estos niveles; sin embargo, aumentan nuevamente después de 12 semanas de tratamiento. El propósito de este estudio fue evaluar los cambios estructurales y funcionales en el ventrículo izquierdo en pacientes con insuficiencia diastólica tratados con ARA angiotensina (NYHAI-III). Métodos. Veintiocho pacientes con insuficiencia cardiaca diastólica en tratamiento con BB, IECA y/o ARA se aleatorizaron a recibir una dosis media de 37.5 mg una vez al día de espironolactona (grupo A) (n - 14, edad 63.7 ± 0 21.6 años e índice masa corporal IMC 27.5 ± 9.4), o no (grupo B, n =14, edad 64.8 ± 11.9, IMC 26.9 ± 4.7). Todos los pacientes fueron seguidos por 13.79 ± 0.99 meses. Resultados. De los pacientes del grupo A, 42.8% y el 55 del grupo B (p = 0.2), tenían cardiopatía isquémica. No se encontraron diferencias significativas en otras comorbilidades. El porcentaje promedio de cambios en el ecocardiograma se observó en septum interventricular (SIV) -12.2 ± 11% vs. 1.3 ± 15.3% (p = 0.02), y la presión sistólica de la arteria pulmonar (PSAP, 0.99 ± 3.8% vs. 10.5 ± 9.1, p = 0.05, para los grupos A y B, respectivamente). Los otros parámetros no mostraron diferencias estadísticamente significativas. Conclusión. El tratamiento con antagonistas de receptores de aldosterona disminuye o limita aumentos de PSAP e inducen una remodelación favorable del ventrículo izquierdo, especialmente del SIV en pacientes con insuficiencia cardiaca diastólica.

A Korean Family of Hypokalemic Periodic Paralysis with Mutation in a Voltage-gated Calcium Channel (R1239G)

Hypokalemic periodic paralysis (HOPP) is a rare disease characterized by reversible attacks of muscle weakness accompanied by episodic hypokalemia. Recent molecular work has revealed that the majority of familial HOPP is due to mutations in a skeletal muscle voltage-dependent calcium-channel: the dihydropyridine receptor. We report a 13-yr old boy with HOPP from a family in which 6 members are affected in three generations. Genetic examination identified a nucleotide 3705 C to G mutation in exon 30 of the calcium channel gene, CACNA1S. This mutation predicts a codon change from arginine to glycine at the amino acid position #1239 (R1239G). Among the three known mutations of the CACNA1S gene, the R1239G mutation was rarely reported. This boy and the other family members who did not respond to acetazolamide, showed a marked improvement of the paralytic symptoms after spironolactone treatment.

In vitro evaluation and in vivo pharmacodynamic studies of spironolactone suppositories administered to rats

In vitro release of spironolactone from different suppository bases and in vivo pharmacodynamic effect in rats were studied. Suppositories containing 10 mg of spironolactone were prepared using polyethylene glycol [PEG], Witepsol E75, theobroma oil and Suppocire A. The hardness test of the suppositories revealed that the theobroma oil base produced relatively brittle suppositories, whereas polyethylene glycol base, in particular mixture of 1000: 4000 produced hard and stable suppositories. The release of spironolactone was fast from polyethylene glycol bases. Incorporation of Tween 80 in lipophilic bases remarkably enhanced the release of spironolactone from these bases. Using the dialyzing technique to study release characteristics of the drug from the suppositories, the maximum release of the drug was obtained from Witepsol E75 suppositories containing 5%Tween 80 followed by release from PEGs. The suppository formulations were evaluated for their pharma effect in rats. The in vivo data showed that the different suppository formulations had a significant influence on the extent of spironolactone dynamic effect. Among these suppository bases, the hydrophilic polyethylene glycol 1500, Witepsol E75+5% Tween 80 and theobroma oil were found to be the best

Aldosterone Upregulates Connective Tissue Growth Factor Gene Expression via p38 MAPK Pathway and Mineralocorticoid Receptor in Ventricular Myocytes

The effect of aldosterone on connective tissue growth factor (CTGF) was examined in rat embryonic ventricular myocytes. Upon aldosterone treatment, CTGF expression was significantly increased in a dose and time-dependent manner. To explore the molecular mechanism for this upregulation, we examined the role of mineralocorticoid receptor. Pre-treatment of an antagonist (spironolactone) at 5-fold excess of aldosterone blocked the CTGF induction by aldosterone, suggesting that the upregulation was mediated by mineralocorticoid receptor. Aldosterone treatment resulted in activation of ERK1/2, p38 MAPK, and JNK pathways with a more transient pat-tern in p38 MAPK. Blocking studies using pre-treatment of the inhibitor of each path-way revealed that p38 MAPK cascade may be important for aldosterone-mediated CTGF upregulation as evidenced by the blocking of CTGF induction by SB203580 (p38 MAPK inhibitor), but not by PD098059 (ERK1/2 inhibitor) and JNK inhibitor I. Interestingly, JNK inhibitor I and PD098059 decreased the basal level of CTGF expression. On the other hand, pre-treatment of spironolactone abrogated the p38 MAPK activation, indicating that mineralocorticoid receptor mechanism is linked to p38 MAPK pathway. Taken together, our findings suggest that aldosterone induces CTGF expression via both p38 MAPK cascade and mineralocorticoid receptor and that cross-talk exists between the two pathways.

Tratamiento del hirsutismo con espironolactona y con espironolactona más dexametasona / Treatment of hirsutism with spironolactone and with spironolactone plus dexamethasone

Background: Spironolactone has an anti androgenic effect, inhibiting the binding of androgens to their receptor. This antagonistic effect is the basis for the use of spironolactone in the treatment of hirsutism. Aim: To study the effectiveness and safety of spironolactone in the treatment of hirsute women and of the association of spironolactone plus dexamethasone in the treatment of hirsutism with glucocorticoid sensitive hyperandrogenism. Patients and method: Sixteen women (group 1) with peripheral hirsutism (defined as those with normal androgens levels, normal menstrual cycles and ovulation) and 24 women (group 2) with glucocorticoid sensitive hyperandrogenic hirsutism were studied. Group 1 was treated with spironolactone 50 mg bid and group 2 with same spironolactone dose plus dexamethasone 0.5 mg at 23 h during one month and 0.25 mg thereafter. Patients were followed during one year. Results: After one year of treatment, a 54 percent reduction in Moncada hirsutism escore was observed in group 1 and 52 percent reduction in group 2. Observed secondary effects of spironolactone were increases in diuresis, fatigability, acne aggravation and seborrhea in two patients. Two additional patients had spotting. No secondary effect attributable to glucocorticoid use were observed. Conclusions: Spironolactone is effective and safe in the treatment of hirsutism. Androgenic supression did no increases its effectiveness, underscoring the peripheral anti androgenic activity os spironolactone

Inhibitory effect of spironolactone on the contractions of the rabbit uterine horn and the human myometrial strip.

The spontaneous contractions of the rabbit uterine horns and the human myometrial strips were stimulated by oxytocin and buserelin acetate in isolated preparations. Spironolactone application to these models produced inhibitory effects on the contractions. It is concluded that spironolactone has inhibitory effect on the rabbit uterine horn and the human myometrial strip contractions.

Diuretic, natriuretic and kaliuretic effects of dexamethasone

1. Thrombus formation induced by electrical stimulation of the carotid artery was investigated in anesthetized rabbits and rats. Occlusive Grade III thrombi were produced consistently in 34 normal New Zealand rabbits and 58 untreated albino Wistar rats. Thrombus formation was monitored continuously in some of the animals with a magnetic flowmeter or a thermistor probe applied on the carotid. 2. The usefulness of the model for the screening of drugs was tested by treating the animals with warfarin, heparin, prostacyclin (PGI2), dihydroprostacyclin (DiHPGI2), prostaglendin E1 (PGE1), and prostaglandin D2(PGD2). 3. All of the drugs except warfarin were infused continuously into the venous circulation during the entire experimental period at a rat of 0.2 ml/min. 4. Warfarin (10 mg/Kg), administered by gavage 24 h before experimental, prevented thrombus formation, as did heparin iv (> 34 U/Kg). 5. Of the four platelet antiaggregatory prostaglandins tested, PGI2 was the most potent inhibitor of thrombus formation and DiHPGI2 the least active, as evaluated by visual inspection of stimulated arterial segments which were excised 30 min (rabbits) or 15 min (rats) after the stimulation was stopped. PGI2 was less active in rats than in rabbits (Threshold Protective Dose ratio ca. 4:1). PGE1 and PGD2 showed intermediate activity in both animal models

Influence of uridine diphosphoglucuronic acid on bilirubin glucuronidation in liver microsomes from normal and spironolactone treated rats

En el presente trabajo se estudió la formación de glucuronoconjugados de bilirrubina por microsomas hepáticos de ratas normales y tratadas con el inductor espironolactona (SP). A los efectos de analizar la influencia del ácido uridina difosfoglucurónico (UDPGA) sobre dicho proceso se incorporaron cantidades crecientes de éste a las mezclas de incubación. Los microsomas de ratas tratadas con SP mostraron mayor capacidad de formación de glucurónidos de bilirrubina que los correspondientes testigos, fundamentalmente a expensas del diglucurónido (BDG). Por otro lado, al utilizar concentraciones crecientes de UDPGA en los medios de incubación, aumentó la formación de BDG en mayor proporción que la del monoglucurónido. Doicho comportamiento apoya la hipótesis de la existencia de diferentes subunidades enzimáticas glucuronizantes, con diferentes sespecificidades de sustrato. Por su parte, SP representa un efectivo inductor de la glucuronoconjugación de la bilirrubina, corroborando lo observado previamente en el animal entero