Neural Dopaminergic Vasodilator Control in the Kidney

Abstract

As the renal vascular beds of dog and man have been shown to contain inhibitory receptors which seem to be specific for dopamine (DA)^1,2 and the kidneys of a number of species contain high levels of DA ^3,4, it has been suggested that DA may constitute an endogenous vasodilator factor in the regulation of renal function^2,5. The existence in the central nervous system of neurones which seem to use DA as a transmitter has been established by histochemical and biochemical techniques⁶, and it is reasonable to consider that if DA were concerned in renal vascular control then this might be mediated through dopaminergic nerves. On the other hand, studies in which renal blood flow has been measured during stimulation of the peripheral renal nerves have not succeeded in demonstrating the existence of any vasodilator innervation of the renal vasculature^7–9. We have adopted a different approach to this question by recording renal blood flow while electrically stimulating specific loci in the mid-brain and hypothalamus.