Kidney Disease Research Updates
Kidney Dopamine Found to Regulate Blood Pressure, Life Span
The importance of dopamine as a neurotransmitter in the brain and throughout the body is well appreciated. However, researchers at the Vanderbilt University School of Medicine, led by Ming-Zhi Zhang, M.D., and Raymond Harris, M.D., have discovered yet another essential role of dopamine synthesized in the kidney.
Using knockout mice lacking the amino acid decarboxylase, a key element in the synthesis of dopamine inside the kidney, the Vanderbilt researchers sought to distinguish the role of intrarenal dopamine from extrarenal dopamine.
The researchers’ findings showed that dopamine synthesized in the kidney regulates blood pressure. The knockout mice exhibited increased expression of nephron sodium transporters and decreased excretion of salt in the urine as well as decreased urine production, resulting in saltsensitive hypertension. The mice had increased renin expression and other related alterations to the renin-angiotensin system associated with renal injury.
Perhaps most important, the knockout mice had a shorter life span than that of wild-type mice. In other words, dopamine synthesized in the kidney has a positive relationship with lifespan. Zhang and colleagues concluded, “These results demonstrate the importance of the intrarenal dopaminergic system in salt and water homeostasis and blood pressure control. Decreasing intrarenal dopamine...results in the development of hypertension and a dramatic decrease in longevity.”
NIH Publication No. 12–4531
Page last updated June 26, 2012