Dopaminergic neurons produce the monoamine neurotransmitter dopamine and are involved in voluntary movement, memory, emotional and motivated behaviors, and neuroendocrine regulation. The mammalian brain contains nine different dopaminergic neuron cell groups that are dispersed throughout the midbrain, hypothalamus, and olfactory bulb. The axons of these neurons project to their target areas via dopaminergic pathways. There are four main dopamine pathways in the brain: the tuberoinfundibular pathway, the mesolimbic pathway, the mesocortical pathway, and the nigrostriatal pathway. Dysregulation of dopamine signaling has been associated with addiction, schizophrenia, bipolar disorder, and attention deficit hyperactivity disorder. In addition, a reduction of dopamine function in the nigrostriatal pathway due to the loss of dopamine neurons in the substantia nigra is one main pathological feature of Parkinson’s disease.
Tyrosine Hydroxylase in Human Brain.
Tyrosine Hydroxylase was detected in immersion-fixed paraffin-embedded sections of human brain (medulla) using a Mouse Anti-Human/Mouse Tyrosine Hydroxylase Monoclonal Antibody (R&D Systems, Catalog # MAB7566
). The tissue was stained using the Anti-Mouse HRP-DAB Cell & Tissue Staining Kit (R&D Systems, Catalog # CTS002
; brown) and counterstained with hematoxylin (blue). Specific staining was localized to neurons.