Lumbar cerebrospinal fluid choline in healthy aging and in Down's syndrome
M. B. Schapiro, J. R. Atack, I. Hanin, C. May, J. V. Haxby and S. I. Rapoport
Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD.
Choline concentrations were measured in lumbar cerebrospinal fluid (CSF)
and plasma of 37 healthy normal subjects and 13 young (age range, 21 to 34
years) and 6 older (age, greater than or equal to 45 years) healthy adults
with Down's syndrome (DS). All subjects with DS had a trisomy 21 karyotype,
and 3 of the 6 older subjects were demented as judged from a history of
mental deterioration, disorientation, and memory loss. In healthy normal
subjects, there was a significant correlation between age and CSF choline
concentrations. Compared with age-matched controls, in young subjects with
DS, CSF, but not plasma, choline concentrations were elevated (by 49%),
whereas in older subjects with DS, CSF and plasma choline concentrations
were similar to control values. The CSF choline concentrations were
unrelated to body height in the DS and control groups, and rostrocaudal CSF
choline gradients did not differ between either the control and DS groups
or the young and old subjects with DS, suggesting that the elevation in the
CSF choline concentration in young subjects with DS was not related to
their shorter stature. Since increased CSF choline concentrations in young
adult subjects with DS were accompanied by normal plasma choline
concentrations, these results suggest that young adults with DS have either
an increased release of choline from the brain or a reduced rate of
clearance of choline from CSF.
