Dopamine (DA) is an endogenous catecholamine, which serves as a biochemical precursor of norepinephrine and epinephrine. DA is well known as a neurotransmitter in the central nervous system. During the past decade, however, DA has been characterized as an important modulator of BP, Na+ balance, renal and adrenal function through an independent peripheral dopaminergic system. Evidence indicates that DA is synthesized locally within the kidney and acts at adjacent cells in an autocrine or paracrine fashion to control renal Na+ excretion (1,2).