Corticosterone is a glucocorticoid secreted by the cortex of the adrenal gland in response to stimulation by adrenocorticotropic hormone. Corticosterone is a major indicator of stress in non-human mammals. Glucocorticoids, such as corticosterone, guide fundamental processes associated with converting sugar, fat, and protein stores to useable energy; inhibiting swelling and inflammation, and suppressing immune responses following a stress event.
Measuring Corticosterone
Competitive immunoassays, such as RIA and EIA methods, are the typical means for measuring levels of corticosterone in biological matrices. Most RIAs or EIAs require solvent extraction techniques to measure serum or plasma corticosterone levels, however extraction may be very difficult or impossible with mouse samples due to the large volumes of plasma or serum required for most extraction protocols.
Some kits allow the quantification of corticosterone from as little as 1 ul serum / plasma. The principle of these kits is that serum or plasma samples are treated with an equal volume of a special Dissociation Reagent that liberates the corticosterone from any binding proteins. The mixture is then diluted 1:50 or greater with Assay Buffer and added directly to the well of the provided microtiter plate.Typical c57bl/6j mouse serum corticosterone levels fall at 0.08 ± 0.01 µM and therefore can be measured in this assay without extraction.
So keep cool and relax… this kit has been used in many publications (about 20 in the last few months that I am aware of). And in order to keep even cooler in the summer, first-time users are elligible for a 15% discount offer currently.
Quantifying other markers such as cortisol, estradiol…? Leave your comments below!