Adrenalectomy in rats depresses hypoxic pulmonary vasoconstriction in vitro but does not attenuate the pulmonary hypertension of chronic hypoxia (part 3)

12 Aug
2012

 Lungs from adrenalectomized rats were perfused with blood obtained from adrenalecto-mized blood donors, and lungs from sham-operated controls were perfused with blood from control rats. The perfusion flow rate was held constant at 7 mL/min/100 g of body weight of the lung donors. The temperature of the lungs and recirculated blood was controlled at 38°C. Mean perfusion pressure was recorded. The peak increase in perfusion pressure during the response to a given stimulus was measured as the pressor response.Lungs were ventilated for 15 mins with normoxic gas. After the preparation was stabilized, two 10 min hypoxic challenges with 3% O2 + 5% CO2 + 92% N2 were performed. At 45 mins a dose-pressor response to hypoxic challenges was measured by ventilating the lungs with 10%, 3% and 0% O2 (+ 5% CO2, balance nitrogen). The hypoxic mixtures were used in a stepwise manner, each step lasting 10 mins. Then the lungs recovered for 10 mins in normoxic gas, and pressor responses to angiotensin II injections were measured. Doses of 0.1,0.2,0.3,0.4 and 0.5 g of angiotensin II were injected as a bolus in the inflow cannula of the lungs ventilated with the normoxic gas mixture at 5 min intervals. Ten minutes after the last dose of angiotensin II was injected, pressor responses to acute hypoxia were measured as described above. Take advantage of this unique opportunity to pay less money and get yourself a trusted pharmacy where you can always enjoy a chance to buy female viagra online and be sure you will enjoy lowest prices online.

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