For 30 min and reperfused for 15 min at the same flow rate

For 30 min and reperfused for 15 min at the same flow rate used before ischemia. The duration of ischemia and reperfusion were chosen on the basis of previous studies demonstrating decreases in the endothelium-dependent coronary relaxation without alteration of endothelium-independent coronary relaxation [24,25]. The control hearts were perfused during a similar total time (60 min) at constant flow without ischemia. After I/R or perfusion during 60 min the coronary vasoconstriction to angiotensin II or the vasodilatation to bradykinin was recorded. Angiotensin II wasFigure 1. Schematic representation of the experimental set up used to measure coronary perfusion pressure and intraventricular pressure in the perfused rat heart. doi:10.1371/journal.pone.0054984.gEffects of Ischemia in Early Overnutritioninjected into the perfusion cannula with an infusion pump over 3 min at a constant rate to reach a final concentration of 10211?1027 M. The relaxation to bradykinin was recorded after precontracting the coronary arteries with the thromboxane A2 analogue U46619. First, 1028 M U46619 was added to the perfusion solution and the concentration was increased progressively until a contractile tone of ,120?40 mmHg was obtained. The concentrations of U46619 required to achieve this effect were 161028 to 361028 M in control conditions and 561028 to 261027 M after I/R. When the contractile tone reached a stable level, bradykinin was injected into the perfusion cannula over 2 min at a constant rate to reach a final concentration of 1029?1026 M. As the experiments were performed at a constant flow rate, the coronary perfusion pressure provides a measure of the perfusion Castanospermine resistance and characterizes the contraction or relaxation of the coronary arteries.amplification according to the manufacturer’s protocol in a Step One machine (Applied Biosystems). Values were normalized to the housekeeping gene 18S (Rn01428915). According to manufacturer’s guidelines, the DDCT method was used to determine relative expression levels. Statistics were performed using DDCT values [27].Statistical AnalysisValues are expressed as the mean (6 SEM), and compared before and after I/R in rats from control or reduced litters by two way ANOVA. A p value of ,0.05 was considered Madrasin site significant.Drugs and ChemicalsThe following substances were all obtained from Sigma (Tres Cantos, Madrid, Spain): Angiotensin 15857111 II acetate; bradykinin acetate and 9,11-dideoxy-1a,9a-epoxymethanoprostaglandin F2a (U46619).Tissue Homogenization and Protein QuantificationHeart tissue was homogenized in 500 ml of radioimmunoprecipitation assay lysis buffer with an EDTA-free protease inhibitor cocktail (Roche Diagnostics, Mannheim, Germany). After homogenization, samples were centrifuged at 14,000 rpm for 20 min at 4uC. Supernatants were transferred to a new tube and protein concentration was estimated by Bradford protein assay.Results Body Weight, Fat Mass, Leptin and Angiotensin II Serum LevelsRats raised in small litters had increased body weight and leptin serum levels at weaning (P,0.001 for both, Table 1), as well as increased epidydimal and subcutaneous fat weights (P,0.001 for both, Table 1) compared to rats raised in control litters. On the contrary angiotensin II serum levels were unchanged between control and overfed rats (Table 1).ImmunoblottingIn each assay the same amount of protein was loaded in all wells (75 mg) and resolving gels with different amount of SDSacrylamide gels (8?2 ) were used depend.For 30 min and reperfused for 15 min at the same flow rate used before ischemia. The duration of ischemia and reperfusion were chosen on the basis of previous studies demonstrating decreases in the endothelium-dependent coronary relaxation without alteration of endothelium-independent coronary relaxation [24,25]. The control hearts were perfused during a similar total time (60 min) at constant flow without ischemia. After I/R or perfusion during 60 min the coronary vasoconstriction to angiotensin II or the vasodilatation to bradykinin was recorded. Angiotensin II wasFigure 1. Schematic representation of the experimental set up used to measure coronary perfusion pressure and intraventricular pressure in the perfused rat heart. doi:10.1371/journal.pone.0054984.gEffects of Ischemia in Early Overnutritioninjected into the perfusion cannula with an infusion pump over 3 min at a constant rate to reach a final concentration of 10211?1027 M. The relaxation to bradykinin was recorded after precontracting the coronary arteries with the thromboxane A2 analogue U46619. First, 1028 M U46619 was added to the perfusion solution and the concentration was increased progressively until a contractile tone of ,120?40 mmHg was obtained. The concentrations of U46619 required to achieve this effect were 161028 to 361028 M in control conditions and 561028 to 261027 M after I/R. When the contractile tone reached a stable level, bradykinin was injected into the perfusion cannula over 2 min at a constant rate to reach a final concentration of 1029?1026 M. As the experiments were performed at a constant flow rate, the coronary perfusion pressure provides a measure of the perfusion resistance and characterizes the contraction or relaxation of the coronary arteries.amplification according to the manufacturer’s protocol in a Step One machine (Applied Biosystems). Values were normalized to the housekeeping gene 18S (Rn01428915). According to manufacturer’s guidelines, the DDCT method was used to determine relative expression levels. Statistics were performed using DDCT values [27].Statistical AnalysisValues are expressed as the mean (6 SEM), and compared before and after I/R in rats from control or reduced litters by two way ANOVA. A p value of ,0.05 was considered significant.Drugs and ChemicalsThe following substances were all obtained from Sigma (Tres Cantos, Madrid, Spain): Angiotensin 15857111 II acetate; bradykinin acetate and 9,11-dideoxy-1a,9a-epoxymethanoprostaglandin F2a (U46619).Tissue Homogenization and Protein QuantificationHeart tissue was homogenized in 500 ml of radioimmunoprecipitation assay lysis buffer with an EDTA-free protease inhibitor cocktail (Roche Diagnostics, Mannheim, Germany). After homogenization, samples were centrifuged at 14,000 rpm for 20 min at 4uC. Supernatants were transferred to a new tube and protein concentration was estimated by Bradford protein assay.Results Body Weight, Fat Mass, Leptin and Angiotensin II Serum LevelsRats raised in small litters had increased body weight and leptin serum levels at weaning (P,0.001 for both, Table 1), as well as increased epidydimal and subcutaneous fat weights (P,0.001 for both, Table 1) compared to rats raised in control litters. On the contrary angiotensin II serum levels were unchanged between control and overfed rats (Table 1).ImmunoblottingIn each assay the same amount of protein was loaded in all wells (75 mg) and resolving gels with different amount of SDSacrylamide gels (8?2 ) were used depend.