Cognitive decline and frailty exacerbated by chronic polypharmacy are caused by anticholinergic burden, possibly impairing psychosomatic functions of elderly people. However, elucidating the anticholinergic burden on dementia is difficult, as techniques that measure anticholinergic activity (AA) in the body have not yet been established. In 1980, Tune et al., established a serum AA (SAA) assay technique that inhibits the binding of [3H]-quinuclidinyl benzylate ([3H]-QNB) to the membrane fraction of a rat’s forebrain homogenate.
However, the procedure resulted in varying IC50 values of specific compounds among the researchers due to the use of rat forebrain homogenate membrane fractions. Therefore, Nobrega et al., utilized M1 muscarinic receptor subtype expressing cells from the brain homogenate instead of membrane fractions. However, this procedure took longer and egested a large amount of radioactive waste materials.
In this study, we used MeltiLex as a melt-on scintillator, instead of a liquid scintillator to perform cost-effective and rapid measurements.
This modified procedure for measuring SAA is faster, reduces the time required to 1/20 of the initial time; is economical, lowers cost to 1/30 of the initial cost; and reduces the quantity of radioactive waste, reduces wasted liquid to 1/80 and solid materials to 1/60 of previous quantities. Using this procedure to measure SAA is efficient and useful in diagnosing dementia associated with prescribed medicines. It also ensures the proper use of drugs in patients.
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