A rapid and reliable radioreceptor assay for measuring endogenous opiate peptides in human CSF and plasma has been developed. The method is based on the competition between [ 3H]-[D-Ala 2]enkephalin-(L-leu-amide) 5 and biologically active opioids for binding sites using crude rat brain membranes. Sensitivity is about 250 fmol/ml sample; 100 μl of plasma or CSF inhibit the total binding within the range of 25-75%. At therapeutic concentrations, psychotropic drugs do not interfere with the assay. Elution profiles of CSF and plasma show two major peaks, probably representing endorphin-like and enkephalin-like compounds. Normal levels, expressed in β-endorphin-like activity, are 1.4-4.8 pmol/ml for extracted plasma and 7.1-15.8 pmol/ml for CSF.
|Original language||English (US)|
|Number of pages||9|
|Journal||Substance and Alcohol Actions/Misuse|
|State||Published - 1980|
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