Neurotransmitter synthesis by SN6 cell lines, a family of hybrid cell lines of embryonic septal origin

In order to clarify why multiple neurotransmitter phenotypes are present in a septal cholinergic hybrid cell line, two different batches and two subclones of it were characterized from the neurochemical point of view. It was found that besides morphological differences, tyrosine hydroxilase (TH), the rate limiting enzyme in catecholamine-synthesis, was missing in one of the clones, SN6.1b. We propose that this simplification of the neurotransmitter phenotype may represent a more differentiated state for SN6.1b than that of the mother cell line.