has part has part has_part occurs in occurs in characteristic of part of has modifier synapse norepinephrine secretion abnormal neurotransmitter secretion abnormal synaptic norepinephrine release aberrant secretion across synapses of this widespread central and autonomic neurotransmitter, the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus MPheno.ontology MP:0005447 quality abnormal