Adrenalectomy in rats depresses hypoxic pulmonary vasoconstriction in vitro but does not attenuate the pulmonary hypertension of chronic hypoxia (part 13)

22 Aug
2012

chronic hypoxia (part 13)

Similarly, in isolated lungs perfused with saline albumin solution, which usually show poor or no reactivity to hypoxia, injection of angiotensin II substantially increased reactivity to hypoxic challenges . The same effect was also seen with other excitatory substances such as noradrenaline, 4-amidopyridine, plasma or K+ . This effect of agonists on vascular reactivity may be explained by an increase in the basal tone of pulmonary vascular smooth muscle. Such an increase does not necessarily mean a considerable rise in basal perfusion pressure .The level of basal tone has an important influence on pulmonary vascular reactivity . Therefore, the presence of glucocorticoids may prevent a decrease in pulmonary vascular smooth muscle basal tone and consequent decrease in vascular reactivity in in vitro conditions.

In conclusion, we found that the effects of adrenalectomy on pulmonary vascular reactivity to hypoxia differ in acute and chronic conditions. While acute hypoxic vasoconstric-tions are depressed after adrenalectomy, the effects of chronic exposure to hypoxia on the pulmonary vascular bed are not altered. Choose a perfect onlinepharmacy to get viagra superactiveonline click here and treat your health issue.

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