Washington, July 20 : Scientists at the Vanderbilt University Medical Centre have found that dopamine produced outside the brain - in the kidneys - is important for renal function, blood pressure regulation and our life span.

The finding suggests that the kidney-specific dopamine system may be a therapeutic target for treating hypertension and kidney diseases such as diabetic nephropathy.

To explore dopamine's role in the kidney, Vanderbilt Raymond Harris and Ming-Zhi Zhang 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.

These results suggest kidney dopamine 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.

The study has been published in the July Journal of Clinical Investigation. (ANI)