Quantitation of cholinergic synaptosomes from guinea pig brain.

An antiserum raised to nerve terminal sacs derived from the electric organ and Torpedo marmorata was used to lyse guinea pig brain synaptosomes in the presence of complement. From the release of the cytoplasmic enzymes choline acetyltransferase, lactate dehydrogenase, tyrosine hydroxylase and glutamate decarboxylase it appears that the antiserum binds specifically to cholinergic terminals. The amount of lactate dehydrogenase released was used to estimate the proportion of cholinergic nerve terminals in different synaptosome preparations.