Hyponatremia feedback loop is overwhelmed by increased fluid intake, 2) the feedback loop malfunctions such that ADH is always "turned on"; 3) the receptors in the kidney are always "open" regardless of there being no signal from ADH to be open; or 4) there is an increased ADH even though there is no normal stimulus (elevated serum sodium) for ADH to be increased. Hyponatremia occurs in one of two ways: either the osmoreceptor-aquaporin feedback loop is "overwhelmed", or it is "interrupted". If it is interrupted, it is either "related" or "not related" to ADH. If the feedback system is overwhelmed, this
Serum-separating tube particles to cause blood to clot quickly. The blood sample may then be centrifuged, allowing the clear serum to be removed for testing. These tubes should be used with care when measuring drug or hormone levels because the drug or hormone may diffuse from the serum into the gel, causing a reduction in measured level. The gel in SST II tubes (which appears slightly less opaque) is supposed to have less effect on drug levels in serum. Serum-separating tube Serum-separating tubes, also known as serum separator tubes or SSTs, are used in medical clinical chemistry tests requiring blood serum. SSTs