Journal of Neuroscience, Vol 9, 106-114, Copyright © 1989 by Society for Neuroscience
Flow cytometric analysis and isolation of permeabilized dopamine nerve terminals from rat striatum
ME Wolf and G Kapatos
Center for Cell Biology, Sinai Research Institute, Detroit, Michigan 48235.
Fluorescence-activated cell sorting (FACS) was used to identify and isolate
permeabilized dopaminergic nerve terminals from rat striatum based on
immunofluorescent labeling of tyrosine hydroxylase (TH). Striatal
synaptosomes were permeabilized by fixation with modified Zamboni fluid. A
highly fluorescent subpopulation of particles was detected by FACS
following sequential incubation with a monoclonal antibody to TH (LNC 1)
and a fluorescein-conjugated secondary antibody. After correcting for
nonsynaptosomal particles present in the synaptosomal fraction, analysis of
these data suggested that approximately 12-15% of striatal synaptosomes
were dopaminergic, consistent with previous estimates. Specific labelling
by LNC 1 was decreased if synaptosomes were prepared from rats that had
received intraventricular injections of 6-hydroxydopamine. The decrease in
labeling was highly correlated with the extent of the lesion as determined
by measurement of striatal dopamine levels, suggesting that LNC 1-labeled
synaptosomes were derived from nigrostriatal dopamine terminals. In order
to verify that LNC 1-labeled synaptosomes were enriched for TH, equal
numbers of labeled and control synaptosomes were isolated by FACS and
analyzed by SDS-PAGE. LNC 1-labeled synaptosomes were shown by Western blot
techniques to be enriched 6-fold for TH compared with control synaptosomes,
suggesting that the labeled population consisted almost entirely of
dopaminergic synaptosomes.