9% NaCl, 0.1 ml/100 g, s.c.; control group). At the end of the 7-day period, the rats were killed by decapitation and the hearts were immediately removed. Wet weights of left ventricles were recorded, normalized for body weight and then expressed as cardiac mass index (mg/g). The left ventricles were GSK126 cell line used for histology and western blot analysis. SD rats (n = 8–10) were nephrectomized (left kidney) under tribromethanol (0.25 g/kg, i.p.) anesthesia. Part of the animals (DOCA)

were implanted with a subcutaneous pellet (Silicone rubber encapsulant, Down-Corning) containing deoxycorticosterone acetate (DOCA; 200 mg/kg; Sigma) and had a solution of 0.9% NaCl and 0.2% KCl to drink for 6 weeks, as previously described [21]. Control rats were only uninephrectomized. Systolic arterial pressure (SAP) was evaluated by tail-cuff plethysmography (RTBP2000, Kent Scientific) 1 day before and each 7 days of treatment during 6 weeks. Rats were submitted to echocardiographic evaluation, as previously described [14]. Left ventricular wet weights were recorded, normalized for tibial length and then expressed as cardiac mass index (g/cm). In addition, left ventricles were also APO866 order used for western blot analysis. Under anesthesia

with 10% ketamine/2% xylazine (4:3, 0.1 ml/100 g, i.p.), Wistar rats (n = 3–5) were placed in the supine position on a surgical table, tracheotomized, intubated and ventilated with room air using a respirator for small rodents. The chest was opened by a left thoracotomy at the fourth or fifth intercostal space. To expose the heart, a small-sized retractor was used to maintain the ribs separated. After incision of the Sodium butyrate pericardium, the heart was quickly removed from the thoracic cavity and turned left to allow access to the proximal left anterior descending (LAD) coronary artery. A 4-0 silk suture was snared around the LAD and tightly

ligated to occlude the vessel. The heart was then placed back and the chest was closed with 4-0 silk sutures. Sham-operated rats were treated in the same manner, but the coronary artery was not ligated. At 7 and 21 days after MI, left ventricular samples were used for western blot analysis. Before the sacrifice, the animals were injected with 30 mM KCl to cause cardiac arrest in diastole. Left ventricular samples were kept in 4% Bouin fixative for 24 h at room temperature, dehydrated and imbedded in paraffin. Transversal sections (6 μm) were cut at intervals of 40 μm and stained with Masson’s trichrome to confirm the presence of infarct or with hematoxylin and eosin for cell morphometry, as previously described [6] and [14]. Left ventricular samples were homogenized in lysis buffer containing 50 mM sodium pyrophosphate, 50 mM NaF, 50 mM NaCl, 5 mM EDTA, 5 mM EGTA, 2 mM Na3VO4, 10 mM HEPES pH 7.4, 0.5% Triton 100, 1 mM PMSF, 1 μg/ml leupeptin and 1 μg/ml aprotinin.