Baroreflex – getting to the core of high BP.

In simplicity, the human body has a set of nerves, some in the arteries of the neck and heart that measure and respond to blood pressure — and maintain it.   This response is known as baroreflex.

Baroreflex, or how the body controls blood pressure is complex.  Studies have tried to unravel how it works and affect of exercise on it. It is thought now that during exercise, the blood pressure is set a higher point, and that it resets at the end of exercise.  This raises questions of whether blood pressure can be lowered by exercise, directly causing a resetting to lower values.  Or perhaps somehow, during exercise blood pressure gets caught at higher level, and some other process like slow breathing is needed to reset it to lower values.

http://hyper.ahajournals.org/content/46/4/714.full

Wikipedia says the following …

The baroreflex or baroreceptor reflex is one of the body’s homeostatic mechanisms for maintaining blood pressure. It provides a negative feedback loop in which an elevated blood pressure reflexively causes heart rate to decrease therefore causing blood pressure to decrease; likewise, decreased blood pressure activates the baroreflex, causing heart rate to increase thus causing an increase in blood pressure.

Baroreflex depends on barorecptors in various locations including heart, and neck that measure blood pressure, and send information to the brain stem.   The sympathetic and parasympathetic branches of the autonomic nervous system have opposing effects on blood pressure.

Since the barorecpetors are mechanical measures of blood pressure, it is thought that perhaps a period of high blood pressure, causes their set point to shift.  They start to think that high blood pressure is normal blood pressure.  If so, one wonders could an extended period of lower blood pressure, help the body, reset to a lower point.  Perhaps this is one reason to be sure to keep blood pressure under control.  How long does this process take?  Days, weeks , months, years?  No one knows — but it probably takes weeks at least.

Slow breathing it thought to activate he parasympathetic nerves, and contribute in this manner to lowering of blood pressure.  The beauty of this is that sympathetic and parasympathetic actions oppose each other, activation of parasympathetic shuts down sympathetic.

Two key messages:

#1 Keep your blood pressure under control … high blood pressure may feed higher blood pressure.  Conversely well controlled blood pressure might eventually lead to a cure.

#2 Use slow breathing, ideally Resperate device.  It has power to activate the parasympathetic nerve patterns.