Regulation Of Blood Pressure
When your heart beats, it pumps blood round your body to give it the energy and oxygen it needs. As the blood moves, it pushes against the sides of the blood vessels. The strength of this pushing is your blood pressure. If your blood pressure is too high, it puts extra strain on your arteries (and your heart) and this may lead to heart attacks and strokes.
Regulation Of Blood Pressure:
The endogenous regulation of arterial pressure is not completely understood, but the following mechanisms of regulating arterial pressure have been well-characterized:
Baroreceptor reflex: Baroreceptors in the high pressure receptor zones detect changes in arterial pressure. These baroreceptors send signals ultimately to the medulla of the brain stem, specifically to the rostral ventrolateral medulla (RVLM). The medulla, by way of the autonomic nervous system, adjusts the mean arterial pressure by altering both the force and speed of the heart's contractions, as well as the systemic vascular resistance. The most important arterial baroreceptors are located in the left and right carotid sinuses and in the aortic arch.[50]
Renin–angiotensin system (RAS): This system is generally known for its long-term adjustment of arterial pressure. This system allows the kidney to compensate for loss in blood volume or drops in arterial pressure by activating an endogenous vasoconstrictor known as angiotensin II.
Aldosterone release: This steroid hormone is released from the adrenal cortex in response to angiotensin II or high serum potassium levels. Aldosterone stimulates sodium retention and potassium excretion by the kidneys. Since sodium is the main ion that determines the amount of fluid in the blood vessels by osmosis, aldosterone will increase fluid retention, and indirectly, arterial pressure.
Baroreceptors in low pressure receptor zones (mainly in the venae cavae and the pulmonary veins, and in the atria) result in feedback by regulating the secretion of antidiuretic hormone (ADH/Vasopressin), renin and aldosterone. The resultant increase in blood volume results in an increased cardiac output by the Frank–Starling law of the heart, in turn increasing arterial blood pressure.
These different mechanisms are not necessarily independent of each other, as indicated by the link between the RAS and aldosterone release. When blood pressure falls many physiological cascades commence in order to retVery usefull article thanks ... keep writing such articles :) I'm so happy bcoz you are write this post for everyone thnxx a lot Good night messages for girlfriend Good Morning messages for girlfriend Good night love SMS | Romantic Night SMS Rohit sharma Accountant | Blogger Good Night Messages For Her Girlfriend Impress Images and Wallpapaer I love u messages for girlfriend Good Night Messages for mother Good Night Images HD Wallpaper Happy Diwali Wishes For Girlfriend Diwali Wishes 2018 Good night messages wishes and quotes Raksha Bandhan Wishes For Sister *Raksha Bandhan Wishes* #50 Sweet Good Night Messages For Wife: Romantic Night Quotes For Wife #50 *Girlfriend Propose Messages* Heart Touching Good Morning Messages For Wife Good Morning Messages For Friends Happy New Year Wishes 2019: Best New Year Messages I love u Messages for wife i love u messages for dad i love u messages for son i love u messages for mother good night messages for uncle and aunt good night images for girlfriend good night images for whatsapp and facebook good night quotes messages , wishes, for husband Good Morning Messages For Friends Raksha Bandhan Images Brother and Sister Love Shayari -Love Romantic Shayari Best Whatsapp Status Good Night Text Messages For Her Love Attitude Status For Girls & Boys Good Night - Messages Quotes & Wishes Love Status for girlfriend Diwali Images Good Night QuotesIndependence Day Thoughts Good Night Mesages, Wishes, Quotes Brother-sister Happy Raksha Bandhan Shayari Brother-Sister good night messages for boyfriend Good Morning hd images Happy Diwali Messages For Friends Diwali Quotes For Everybody Happy Diwali Images Happy Diwali Images For Lover good morning hd images Good Morning PicturesGood Morning Images Good Morning Images For Lover Good Morning Images For Girlfriend Good Morning Images For wife Good Morning beautiful pictures Loverelationurn the blood pressure to a more appropriate level.
The blood pressure fall is detected by a decrease in blood flow and thus a decrease in Glomerular filtration rate (GFR).
Decrease in GFR is sensed as a decrease in Na+ levels by the macula densa.
The macula densa cause an increase in Na+ reabsorption, which causes water to follow in via osmosis and leads to an ultimate increase in plasma volume. Further, the macula densa releases adenosine which causes constriction of the afferent arterioles.
At the same time, the juxtaglomerular cells sense the decrease in blood pressure and release renin.
Renin converts angiotensinogen (inactive form) to angiotensin I (active form).
Angiotensin I flows in the bloodstream until it reaches the capillaries of the lungs where angiotensin converting enzyme (ACE) acts on it to convert it into angiotensin II.
Angiotensin II is a vasoconstrictor which will increase bloodflow to the heart and subsequently the preload, ultimately increasing the cardiac output.
Angiotensin II also causes an increase in the release of aldosterone from the adrenal glands.
Aldosterone further increases the Na+ and H2O reabsorption in the distal convoluted tubule of the nephron.
Currently, the RAS is targeted pharmacologically by ACE inhibitors and angiotensin II receptor antagonists. The aldosterone system is directly targeted by spironolactone, an aldosterone antagonist. The fluid retention may be targeted by diuretics; the antihypertensive effect of diuretics is due to its effect on blood volume. Generally, the baroreceptor reflex is not targeted in hypertension because if blocked, individuals may suffer from orthostatic hypotension and fainting.
Regulation Of Blood Pressure:
The endogenous regulation of arterial pressure is not completely understood, but the following mechanisms of regulating arterial pressure have been well-characterized:
Baroreceptor reflex: Baroreceptors in the high pressure receptor zones detect changes in arterial pressure. These baroreceptors send signals ultimately to the medulla of the brain stem, specifically to the rostral ventrolateral medulla (RVLM). The medulla, by way of the autonomic nervous system, adjusts the mean arterial pressure by altering both the force and speed of the heart's contractions, as well as the systemic vascular resistance. The most important arterial baroreceptors are located in the left and right carotid sinuses and in the aortic arch.[50]
Renin–angiotensin system (RAS): This system is generally known for its long-term adjustment of arterial pressure. This system allows the kidney to compensate for loss in blood volume or drops in arterial pressure by activating an endogenous vasoconstrictor known as angiotensin II.
Aldosterone release: This steroid hormone is released from the adrenal cortex in response to angiotensin II or high serum potassium levels. Aldosterone stimulates sodium retention and potassium excretion by the kidneys. Since sodium is the main ion that determines the amount of fluid in the blood vessels by osmosis, aldosterone will increase fluid retention, and indirectly, arterial pressure.
Baroreceptors in low pressure receptor zones (mainly in the venae cavae and the pulmonary veins, and in the atria) result in feedback by regulating the secretion of antidiuretic hormone (ADH/Vasopressin), renin and aldosterone. The resultant increase in blood volume results in an increased cardiac output by the Frank–Starling law of the heart, in turn increasing arterial blood pressure.
These different mechanisms are not necessarily independent of each other, as indicated by the link between the RAS and aldosterone release. When blood pressure falls many physiological cascades commence in order to retVery usefull article thanks ... keep writing such articles :) I'm so happy bcoz you are write this post for everyone thnxx a lot Good night messages for girlfriend Good Morning messages for girlfriend Good night love SMS | Romantic Night SMS Rohit sharma Accountant | Blogger Good Night Messages For Her Girlfriend Impress Images and Wallpapaer I love u messages for girlfriend Good Night Messages for mother Good Night Images HD Wallpaper Happy Diwali Wishes For Girlfriend Diwali Wishes 2018 Good night messages wishes and quotes Raksha Bandhan Wishes For Sister *Raksha Bandhan Wishes* #50 Sweet Good Night Messages For Wife: Romantic Night Quotes For Wife #50 *Girlfriend Propose Messages* Heart Touching Good Morning Messages For Wife Good Morning Messages For Friends Happy New Year Wishes 2019: Best New Year Messages I love u Messages for wife i love u messages for dad i love u messages for son i love u messages for mother good night messages for uncle and aunt good night images for girlfriend good night images for whatsapp and facebook good night quotes messages , wishes, for husband Good Morning Messages For Friends Raksha Bandhan Images Brother and Sister Love Shayari -Love Romantic Shayari Best Whatsapp Status Good Night Text Messages For Her Love Attitude Status For Girls & Boys Good Night - Messages Quotes & Wishes Love Status for girlfriend Diwali Images Good Night QuotesIndependence Day Thoughts Good Night Mesages, Wishes, Quotes Brother-sister Happy Raksha Bandhan Shayari Brother-Sister good night messages for boyfriend Good Morning hd images Happy Diwali Messages For Friends Diwali Quotes For Everybody Happy Diwali Images Happy Diwali Images For Lover good morning hd images Good Morning PicturesGood Morning Images Good Morning Images For Lover Good Morning Images For Girlfriend Good Morning Images For wife Good Morning beautiful pictures Loverelationurn the blood pressure to a more appropriate level.
The blood pressure fall is detected by a decrease in blood flow and thus a decrease in Glomerular filtration rate (GFR).
Decrease in GFR is sensed as a decrease in Na+ levels by the macula densa.
The macula densa cause an increase in Na+ reabsorption, which causes water to follow in via osmosis and leads to an ultimate increase in plasma volume. Further, the macula densa releases adenosine which causes constriction of the afferent arterioles.
At the same time, the juxtaglomerular cells sense the decrease in blood pressure and release renin.
Renin converts angiotensinogen (inactive form) to angiotensin I (active form).
Angiotensin I flows in the bloodstream until it reaches the capillaries of the lungs where angiotensin converting enzyme (ACE) acts on it to convert it into angiotensin II.
Angiotensin II is a vasoconstrictor which will increase bloodflow to the heart and subsequently the preload, ultimately increasing the cardiac output.
Angiotensin II also causes an increase in the release of aldosterone from the adrenal glands.
Aldosterone further increases the Na+ and H2O reabsorption in the distal convoluted tubule of the nephron.
Currently, the RAS is targeted pharmacologically by ACE inhibitors and angiotensin II receptor antagonists. The aldosterone system is directly targeted by spironolactone, an aldosterone antagonist. The fluid retention may be targeted by diuretics; the antihypertensive effect of diuretics is due to its effect on blood volume. Generally, the baroreceptor reflex is not targeted in hypertension because if blocked, individuals may suffer from orthostatic hypotension and fainting.
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