Navigation Links
Kidney dopamine regulates blood pressure, life span
Date:7/19/2011

The neurotransmitter dopamine is best known for its roles in the brain in signaling pathways that control movement, motivation, reward, learning and memory.

Now, Vanderbilt University Medical Center investigators have demonstrated that dopamine produced outside the brain in the kidneys is important for renal function, blood pressure regulation and life span. Their studies, published in the July Journal of Clinical Investigation, suggest that the kidney-specific dopamine system may be a therapeutic target for treating hypertension and kidney diseases such as diabetic nephropathy.

Previous studies had suggested a role for dopamine in regulating kidney function and total body fluid volume, "but how that mechanism works was not clear," said Raymond Harris, M.D., chief of the Division of Nephrology and Hypertension at Vanderbilt.

To explore dopamine's role in the kidney, Harris and Ming-Zhi Zhang, M.D., assistant professor of Medicine at Vanderbilt, eliminated kidney-specific dopamine production in mice (by knocking out a dopamine-generating enzyme only in the kidney) and studied the outcome.

They found that mice lacking kidney dopamine had high blood pressure at baseline and became more hypertensive when they consumed a high-salt diet, suggesting they may be a good model of salt-sensitive (essential) hypertension, Harris said. Alterations in the kidney dopamine system may predispose individuals to hypertension, he noted.

The investigators also showed that elimination of kidney dopamine increased renin production, which activates the angiotensin II system to increase salt and water reabsorption and produce hypertension.

"These animals retain salt and water when they don't have sufficient dopamine production in the kidney," Harris said. "Our studies highlight this whole other hormonal system that appears to balance or put the brakes on the renin-angiotensin system."

Currently, the renin-angiotensin system is the major target for treating chronic kidney diseases. Discovering another target the kidney dopamine system is exciting, the researchers said. They are exploring whether specific drugs that enhance the kidney dopamine system are effective in blocking hypertension and treating progressive kidney diseases.

The investigators predicted changes in kidney function in the mouse model, but they were "very surprised" to discover that the modified mice only lived about half as long as normal mice (15 months versus 30 months). They found increases in stress-related proteins in the kidney, heart and vasculature, suggesting that elimination of kidney dopamine causes systemic effects, Harris said.

"This kidney-specific dopamine system is not only important for kidney function and blood pressure regulation, but also for the overall health of the animal," Harris said. "If the dopamine system in the kidney is altered, the animals have a markedly shortened life span."


'/>"/>

Contact: Leigh MacMillan
leigh.macmillan@vanderbilt.edu
615-322-4747
Vanderbilt University Medical Center
Source:Eurekalert

Related biology news :

1. A mothers salt intake could be key to prenatal kidney development
2. New evidence of the benefits of home dialysis for kidney patients
3. UofL researchers replicate human kidney gene changes in mouse model
4. TGen findings contribute to understanding of diabetic kidney disease
5. Gene variant influences chronic kidney disease risk
6. Study shows pine bark naturally improves kidney function in patients with metabolic syndrome
7. Common congenital defect a prickly problem for the kidney
8. Stem cell transplants help kidney damage
9. Researchers unlock the potential for exploring kidney regeneration
10. Seeing kidney injury, as it happens
11. Kidney gene implicated in increased heart failure risk
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2016)... , April 28, 2016 First quarter ... (139.9), up 966% compared with the first quarter of 2015 ... totaled SEK 589.1 M (loss: 18.8) and the operating margin was ... (loss: 0.32) Cash flow from operations was SEK 249.9 ... 2016 revenue guidance is unchanged, SEK 7,000-8,500 M. The ...
(Date:4/26/2016)... 27, 2016 Research and ... Biometrics Market 2016-2020"  report to their offering.  , ... The analysts forecast the global multimodal biometrics ... during the period 2016-2020.  Multimodal biometrics ... such as the healthcare, BFSI, transportation, automotive, and ...
(Date:4/15/2016)...  A new partnership announced today will help ... in a fraction of the time it takes ... life insurance policies to consumers without requiring inconvenient ... Diagnostics, rapid testing (A1C, Cotinine and HIV) and ... weight, pulse, BMI, and activity data) available at ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... discussions on a range of subjects including policies, debt and ... Poloz. Speaking at a lecture to the Canadian ... to the country,s inflation target, which is set by both ... "In certain areas there needs to be ... why not sit down and address strategy together?" ...
(Date:6/24/2016)... ... June 24, 2016 , ... While the majority of commercial spectrophotometers and fluorometers ... the 6000i models are higher end machines that use the more unconventional z-dimension of ... beam from the bottom of the cuvette holder. , FireflySci has developed several ...
(Date:6/23/2016)... ... June 23, 2016 , ... Mosio, ... second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” Partnering with experienced clinical ... eBook by providing practical tips, tools, and strategies for clinical researchers. , “The ...
(Date:6/23/2016)... , June 23, 2016   Boston ... of novel compounds designed to target cancer stemness ... has been granted Orphan Drug Designation from the ... treatment of gastric cancer, including gastroesophageal junction (GEJ) ... inhibitor designed to inhibit cancer stemness pathways by ...
Breaking Biology Technology: