Exercise-associated hyponatremia cells in one area begin to increase in size, swelling occurs in the affected area. Swelling is commonly observed in hands, legs, and feet. Sodium is also important in regulating the amount of water that passes through the blood-brain barrier. Decreased sodium blood levels result in increased permeability of water across the blood-brain barrier. This increased influx of water causes brain swelling which leads to severe neurological symptoms. EAH is categorized by having a blood serum or plasma sodium level below normal, which is less than 135 mmol/l. Asymptomatic EAH is not normally detected unless the athlete has had a
Fetal bovine serum the harvesting of blood from the bovine fetus after the fetus is removed from the slaughtered cow. The blood is collected aseptically into a sterile container or blood bag and then allowed to clot. The normal method of collection is cardiac puncture, wherein a needle is inserted into the heart. This minimizes "the danger of serum contamination with micro-organisms from the fetus itself, and the environment". It is then centrifuged to remove the fibrin clot and the remaining blood cells from the clear yellow (straw) colored serum. The serum is frozen prior to further processing that is necessary to make