High blood pressure may develop in people with IgA Nephropathy. How do you
get high blood pressure? Based on the mechanism, there are mainly two reasons as
below:
1. Volume-dependent high blood pressure
For people with IgA Nephropathy whose renal parenchyma or renal blood vessels
are damaged, the kidneys' ability to adjust fluid and sodium will be reduced.
When the daily intake of water and sodium exceeds the excretion capacity of the
body, water and sodium retention will occur, which may dilate the blood volume,
causing high blood pressure.
2. Renin-dependent high blood pressure
In case of damage renal parenchyma or blood vessels, the kidney perfusion
will continuously decrease, leading to insufficient supply of oxygen and blood.
When renal ischemia and anoxia appear, the kidneys will secrete a series of
substances which can cause elevated blood pressure. Among these substances, the
most important one is renin produced by jaxtaglomerular cells.
Renin is one important member of the renin-angiotensin system. This system
works together with the kidneys, is the body's most important long-term blood
pressure regulating system. Other members include Angiotensin Ⅰ, Angiotensin Ⅱ,
and Angiotensin Converting Enzyme (ACE).
Renin floats around and converts inactive forms of angiotensin into
angiotensin Ⅰ, which is able to alter the blood pressure to some degree, but it
isn't strong enough to cause large changes.
When angiotensin I passes though pulmonary circulation, it will lose two
amino acids under the influence of ACE, thus leading to the occurrence of
angiotensin Ⅱ, a much more powerful hormone that does cause large changes in
blood pressure.
Furthermore, angiotensin Ⅱalso can stimulate the release of aldosterone,
inducing water and sodium retention. This increase, in turn, raising blood
pressure.
High blood pressure can damage the kidneys and reduce the kidneys' ability to
remove fluids and waste products from the blood, and can result in kidney
failure. Once you develop this complication, you need to take effective measures
to control it vigorously.