Determination of scopolamine in human serum by gas chromatography-ion trap tandem mass spectrometry

The objective of this study was to develop a very sensitive and selective method for the determination of scopolamine in serum with a rapid and simple sample preparation. A capillary column gas chromatographic-ion trap tandem mass spectrometric technique has been applied. Scopolamine and the internal standard mexiletine were extracted from serum samples and cleaned up by using a single step liquid-liquid extraction. Derivatization was carried out using 2,2,2-trifluoro-N-methyl-N-trimethylsilylacetamide. The mass spectrometer was operated with positive ions in the selected reaction mode with chemical ionisation using methane. The sum of peak height of two daughter ions was used for quantification. The detection limit was 50 pg/ml in serum.

[The effect of physical loading on the pharmacokinetics of drugs]

In model experiments on rats performed with the use of radioindication assay and the HPLG method it was shown that the total level of cholinolytics, pediphen (20 mg/kg) and peniphin (6 mg/kg) reliably decreases in plasma after oral administration during physical exercise (method of free swimming under loading). At the same time the intramuscular injection of pediphen (2 mg/kg) and peniphin (0.6 mg/kg) induce a reliable increase in the concentration of cholinolytics in plasma under the influence of physical exercise. The mechanism of observed changes in pharmacokinetics of neurotropic drugs are discussed. The results of this study may be used in therapy to optimize doses of cholinolytic drugs in conditions of physical and/or locomotor activity.

Serum anticholinergic activity in hospitalized older persons with delirium: a preliminary study

OBJECTIVE

To evaluate the relationship between total serum anticholinergic activity (SAA) and the presence or absence of delirium in older hospitalized persons on general medical wards.

DESIGN

Case-control study and within-subjects repeated-measures in recovered delirious patients.

SETTING

Minneapolis Veterans Affairs Medical Center medical wards.

PARTICIPANTS

Eleven male delirious patients (DSM-III-R criteria) aged 60 or older and 11 comparably aged male nondelirious controls.

MEASUREMENTS

Radioreceptor bioassay of total SAA using tritiated quinuclidinyl benzilate (QNB) binding to muscarinic receptors. Results are expressed in terms of atropine equivalents (nM).

MAIN RESULTS

Mean SAA was significantly elevated in the delirious group (mean +/- SD = 6.05 +/- 2.97 nM atropine equivalents) compared with the controls (3.38 +/- 2.49; t(20) = 2.28, P < .05). At study entry, mean SAA was significantly higher in delirious subjects whose symptoms eventually resolved completely (mean +/- SD = 7.77 +/- 2.37) compared with subjects whose delirious symptoms persisted (3.99 +/- 2.30; t(9) = 2.68, P < .05). All six patients in whom delirium resolved completely had a decrease in serum anticholinergic activity when measured during delirium (7.77 +/- 2.37) and after symptom resolution (3.92 +/- 2.61; t(5) = 3.29, P < .05).

CONCLUSIONS

Our findings suggest that serum anticholinergic activity may play a role in delirium in medical inpatients. The relationships between SAA and delirium in medical patients and between total SAA and medication use warrant further study.

Quantitative analysis of bencynonate in human plasma using a deuterated internal standard by gas chromatography-mass spectrometry with selected-ion monitoring

A gas chromatographic-mass spectrometric method is described for the quantitative analysis of bencynonate in human plasma. Deuterated bencynonate served as the internal standard and selected-ion monitoring of the fragments of bencynonate and internal standard permitted the quantitation of bencynonate down to 25 pg/ml of plasma. The assay is linear for plasma bencynonate concentrations in the range 25 pg/ml-3 ng/ml. At 0.25 ng/ml the recovery and coefficient of variation are 54.3% and 19.1%, respectively. Application of the method to clinical studies gave data for the pharmacokinetics and relative bioavailability of bencynonate in man.

A pilot project to assess the association of anticholinergic symptoms with anticholinergic serum levels in the elderly

STUDY OBJECTIVE

To evaluate whether serum anticholinergic drug activity would be a useful clinical tool in helping to predict anticholinergic toxicity.

DESIGN

A prospective study that included a retrospective chart review.

SETTING

Two nursing home facilities.

SUBJECTS

Thirty-one elderly volunteers between ages 69 and 98 years.

INTERVENTION

Each subject completed a two-part interview. First, anticholinergic symptoms were evaluated and then cognitive function was assessed by three neuropsychiatric tests. Blood (10 ml) was collected to measure anticholinergic activity.

MEASUREMENTS AND MAIN RESULTS

Eight subjects had detectable serum anticholinergic activity and scored higher on the Symbol Digit Modalities test than those with no detectable activity. No statistical difference was seen between the groups with respect to symptoms or results of the Mini-Mental and Auditory-Verbal Learning tests.

CONCLUSION

The clinical usefulness of serum anticholinergic activity as a predictor for anticholinergic toxicity was not established under the experimental design of this study.