Causes of High Blood Pressure; the Basics

In order to understand how to fix high systolic blood pressure, you first need to understand more about how your blood vessels work.

Many people think about blood vessels as a tube or pipe.  This is FAR too simplistic.

Human blood vessels are an incredibly complex tissue that responds almost instantaneously responds to its needs.  Watching a movie and your visual cortex needs more blood to process what your eyes are seeing?  The blood vessels feeding this region of the brain open up to improve oxygen and nutrient delivery.  Hear some strange noise in the middle of the night?  The regions of the brain involved with hearing get more blood flow almost instantaneously.

Falling off of a cliff and need to reach out with one single hand to catch that one rock jutting out in your path to certain death (as evidenced by every action movie ever made)?  Blood flow to the forearm increases to save your life.

Extra blood flow to these areas shut off just as quickly once the extra blood is no longer needed.

In other words, it’s an orchestration of such complexity that it is beyond most of our comprehension.

Local and Organ Control

Blood pressure control basically occurs on two levels.

General control of blood pressure is managed by the kidneys and the heart.  The kidneys sense the blood pressure and attempt to control it through several different hormones.  The heart manages blood pressure indirectly by increasing the strength of contraction and speed of the heartbeat.

Renin is a major hormone produced by the kidneys that plays a role in blood pressure regulation.  It does this by a series of events that leads to the production of angiotensin II.  Angiotension II acts to constrict blood vessels.  Constricting blood vessels will raise blood pressure.

Blocking angiotension II or blocking this pathway is the way that a large class of blood pressure medications work.  The angiotensin-converting enzyme (ACE) inhibitors and angiotensin-II receptor blockers (ARBs) like Benicar and Cozaar and valsartan mess with this pathway.

The finesse of blood pressure control happens locally.  Molecules are released that control the dance of blood vessel opening and closing.  The most important of these is nitric oxide, or NO.

NO relaxes the blood vessels, opens them to allow more blood flow as needed to an organ or limb.  NO is created from the amino acid arginine, made by the enzyme nitric oxide synthase.

While you may not think you have heard anything about this enzyme, but I’m pretty sure you have.

Erectile dysfunction drugs like Viagra and Cialis work by manipulating this enzyme.  And you can guess where the extra NO does it’s work when these drugs are used.

The problem with blood pressure medications is that they clamp down a vice on overall blood pressure control.  Under the anvil of blood pressure meds, you lose local control of blood pressure.

In other words, it’s a really bad answer to blood pressure problems.  While you may control the overall big number of blood pressure, you destroy your body’s ability to finesse blood flow when and where it is needed.

Which is where the rest of this story begins.