Hypotonic hyponatremia dramatic increase the serum sodium concentration and place the patient at risk for so-called "central pontine myelinolysis" (CPM). That disorder is characterized by major neurologic damage, often of a permanent nature. Because of the risk of CPM, people with low volume hyponatremia may eventually require water infusion as well as volume replacement. Doing so lessens the chance of a too rapid increase of the serum sodium level as blood volume rises and ADH levels fall. In people who are volume depleted, i.e., their blood volume is too low, ADH secretion is increased, since volume depletion is a potent stimulus for
Blood type (non-human) S, and Z polymorphisms. Blood type (non-human) Animal erythrocytes have cell surface antigens that undergo polymorphism and give rise to blood types. Antigens from the human ABO blood group system are also found in apes and Old World monkeys, and the system traces back to the origin of hominoids. Other animal blood sometimes agglutinates (to varying levels of intensity) with human blood group reagents, but the structure of the blood group antigens in animals is not always identical to those typically found in humans. The classification of most animal blood groups therefore uses different blood typing systems to those used