Pulmonary hypertension is a rare lung disorder in which the arteries that carry blood from the heart to the lungs become narrowed, making it difficult for blood to flow through the vessels. As a result, the blood pressure in these arteries -- called pulmonary arteries -- rises far above normal levels.
Homeostatic Control Mechanisms Homeostatic Control Mechanisms are devices for maintaining or restoring homeostasis. They involve virtually all of the bodyâs organs and systems.
The general mechanisms used by the kidneys for maintaining homeostasis include: 1  Regulation of water volume, blood volume, and interstitial fluid volume. One of the first warning signs that your kidneys are not functioning properly is water retention, or edema -- as evidenced by swelling in your ankles and legs.