Sodium in biology mEq/liter (135 - 145 mmol/L). A serum sodium level of less than 135 mEq/L qualifies as hyponatremia, which is considered severe when the serum sodium level is below 125 mEq/L. The renin–angiotensin system and the atrial natriuretic peptide indirectly regulate the amount of signal transduction in the human central nervous system, which depends on sodium ion motion across the nerve cell membrane, in all nerves. Sodium is thus important in neuron function and osmoregulation between cells and the extracellular fluid; the distribution of sodium ions are mediated in all animals by sodium–potassium pumps, which are active transporter solute pumps, pumping
Hypotonic hyponatremia said than done when one recognizes that the responsible underlying conditions are diseases such as liver cirrhosis or heart failure — conditions that are notoriously difficult to manage, let alone cure. High volume. There is retention of water. Placing the patient on water restriction can also help in these cases. Hypotonic hyponatremia Hypoosmolar hyponatremia is a condition where hyponatremia associated with a low plasma osmolality. The term "hypotonic hyponatremia" is also sometimes used. When the plasma osmolarity is low, the extracellular fluid volume status may be in one of three states: low volume, normal volume, or high volume. Loss of