Dopamine is a neurotransmitter, or brain chemical, produced in several areas of your brain and kidneys. Dopamine is important for voluntary movement, mood, sleep cycles and kidney function, among other roles. Dopamine deficiency is not considered common, but when it occurs it can dramatically affect movement, behavior and blood pressure. Not enough dopamine can cause vasoconstriction, or narrowing, of your blood vessels and lead to hypertension. Dopamine can be administered intravenously to alter heart rate and blood pressure, but not to impact the brain because it doesn't cross the blood-brain barrier.
Dopamine
Dopamine is best known for its various roles within your brain, including those related to cognition, voluntary movement, motivation, sexual gratification, sleep cycle, mood, attention, memory and learning, according to "Human Biochemistry and Disease." Severely reduced dopamine production can cause people to look frozen or be plague by tics and repetitive behavior, as depicted in the book and movie, "Awakenings." However, dopamine is also produced by your kidneys and plays important roles in sodium regulation, urine output, blood vessel size and blood pressure.
Dopamine and Hypertension
Dopamine normally induces natriuresis, or sodium loss, in your kidneys, which leads to diuretic and vasodilating effects, according to the "Textbook for Functional Medicine." In other words, dopamine promotes urination and relaxes blood vessels in and around your kidneys, which increases blood flow and reduces blood pressure. Dopamine deficiency causes vasoconstriction and increases blood pressure, which was demonstrated on mice in a Chinese study published in a 2011 edition of the "Journal of Clinical Investigation." The researchers concluded that dopamine produced by the kidneys is important for salt and water homeostasis and blood pressure control, and lack of it results in hypertension and reduced lifespan.
Complications of Hypertension
Hypertension, or high blood pressure, is usually defined as readings higher than 135 systolic or 85 diastolic pressures, but other factors are usually involved before a diagnosis is given. Unfortunately, hypertension often does not produce any noticeable symptoms, which is why it has been called the "silent killer." Excessively high blood pressure puts strain on the walls of your blood vessels, increasing the risk of aneurysms, and your heart, which increases the risk of heart attacks and congestive heart failure, as explained by Eric Newsholme, author of "Functional Biochemistry in Health and Disease."
Dopamine Treatment
A lack of dopamine production from your brain must be treated with L-DOPA medication because dopamine cannot cross the blood-brain barrier and affect your central nervous system. However, dopamine can be given intravenously for dopamine deficiency of your kidneys, because it is able to act on your sympathetic nervous system and lower blood pressure. Dopamine deficiency is not a common cause of hypertension, so ask your doctor about other, more common causes.
References
- "Human Biochemistry and Disease"; Gerald Litwack; 2008
- "Textbook for Functional Medicine"; David S. Jones; 2005
- "Journal of Clinical Investigation"; Intrarenal dopamine deficiency leads to hypertension and decreased longevity in mice; M.Z. Zhang et al; July 2011
- "Functional Biochemistry in Health and Disease"; Eric Newsholme et al; 2010
