tissue serotonin amount forebrain serotonin amount CMO:0003092 2019-10-30T14:52:55Z VT:0010864 caripark Trait.ontology The proportion, quantity or volume in the forebrain (part of the brain developed from the most rostral of the three primary vesicles of the embryonic neural tube from which the diencephalon and telencephalon are derived) of a monoamine neurotransmitter derived primarily from tryptophan. brain serotonin amount