Cholinesterase activity in plasma, erythrocytes, and cerebrospinal fluid of patients with dementia of the Alzheimer type
Cholinesterases, including pseudocholinesterase (BChE) of human plasma andacetylcholinesterase (AChE) of erythrocytes and cerebrospinal fluid (CSF), havebeen considered as possible markers in dementia of the Alzheimer type (DAT).Reported data, however, are widely varied, and no significant pattern emergeswhen total enzyme activity is assayed. In the present studies, we havereexamined the relationship of ChE activities in DAT and control patients. ChEactivity was measured in plasma, erythrocytes, and CSF from DAT patients andcompared with normal controls as well as with samples from patients with adiagnosis other than DAT. Early age onset (presenile) and late age onset(senile) DAT were also compared. No significant differences in total enzymeactivity were found in any of the comparisons. Calculations of AChE/BChE ratiosin CSF also provided no significant indication of any changes in ChE activitiesin DAT. It is suggested that measurements of total AChE or BChE activity inthese biological materials do not provide a useful index of alterations incentral cholinergic function in patients with DAT.
Marquis J.K., Volicer L., Mark K.A., Direnfeld L.K. & Freedman M.