Capto sp844 mlt844

Langendorf heart preparations were used to assess left ventricular function of the rats in all treatment groups. Terminal anaesthesia was induced via intraperitoneal injection of pentobarbitone sodium (Lethabarb, 100 mg/kg). Heparin (Sigma-Aldrich Australia) was administered (200 IU) through the right femoral vein and blood (~5 mL) was drawn out of the abdominal aorta. Isovolumetric ventricular function was measured by inserting a latex balloon catheter into the LV connected to a Capto SP844 MLT844 physiological pressure transducer and Chart software on a Maclab system (ADInstruments Australia and Pacific Islands). All left ventricular end-diastolic pressure values were measured while pacing the heart at 250 beats/min using an electrical stimulator. End-diastolic pressures were obtained starting from 0 mm Hg up to 30 mm Hg. The diastolic stiffness constant (k, dimensionless) was calculated as in previous studies [20 (link)]. +dP/dt and - dP/dt were calculated as the mean rate of contraction and relaxation, respectively, of at least 50 beats with the heart paced at 250 beats/min, and the end-diastolic pressure was maintained at approximately 10 mmHg.

Isolated Langendorff heart preparations were used to assess left ventricular function of rats [21 (link)]. Hearts isolated from euthanized rats were perfused with modified Krebs-Henseleit bicarbonate buffer bubbled with 95% O₂/5% CO₂ and maintained at 35 °C. Isovolumetric ventricular function was measured by inserting a latex balloon catheter into the left ventricle connected to a Capto SP844 MLT844 physiological pressure transducer (ADInstruments, Sydney, NSW, Australia) and Chart software (5.0, ADInstruments, Sydney, NSW, Australia) on a Maclab system. Left ventricular end-diastolic pressure values were measured during pacing of the heart at 250 beats per minute using an electrical stimulator. End-diastolic pressures were obtained from 0 to 30 mmHg for the calculation of diastolic stiffness constant (κ, dimensionless) [21 (link)].