Paracrine Regulation of Renal Function by Dopamine

Classical transmitter ligands evolved about 1000 million years ago. 1 The role of dopamine as a neurotransmitter has evolved with time. In primordial and plant cells, dopamine is present, even though catecholamine signaling is not used. In invertebrate neural systems, dopamine is the pre-eminent catecholamine. In vertebrates, the catecholamine pathway terminates in norepinephrine and epinephrine. 2 Endogenous dopamine was mainly recognized as a precursor to norepinephrine and epinephrine 3 until the late 1950s, when Carlsson demonstrated that dopamine itself had a transmitter role. 4 This finding, for which he was awarded the Nobel Prize in Physiology or Medicine 2000, was revolutionary for the understanding of various central functions of the brain, including memory, learning, drug abuse, cognition, and attention; it has also enlightened us regarding the pathogenesis and treatment of various psychiatric and neurological disorders.