ISOLATION OF MONOAMINERGIC SYNAPTOSOMES FROM RAT-BRAIN BY IMMUNOMAGNETOPHORESIS

Monoaminergic synaptosomes have been isolated and purified from rat brain by immunomagnetophoresis. This novel technique uses magnetic beads to which Protein A is bound. Noradrenergic, dopaminergic, and serotonergic synaptosomes (previously cell-surface labelled with anti-dopamine-beta-hydroxylase, anti-tyrosine hydroxylase, and antitryptophan hydroxylase, respectively) may be isolated in a highly purified state. The synaptosomal subpopulations are recovered in a viable metabolic state and show glucose-stimulated respiration and Ca2+-dependent neurotransmitter release. A novel subtype of dopamine-beta-hydroxylase was found in dopaminergic terminals. No evidence for glutamate corelease from monoaminergic synaptosomes was obtained.