Long term control of blood pressure Flashcards
what does regulation of blood pressure in the long term revolve around
blood volume
what is it that effects blood pressure in the long-term
hormones
what does not regulate blood pressure in the long term
arterial baroreceptors
what are the main sensors of pressure in the long term regulation of blood pressure
the cardiopulmonary baroreceptors
state 3 hormone systems that regulate blood pressure in the long term
the renin angiotensin aldosterone system
the vasopressin hormone system
the atrial natriuretic factor hormone system
how does the renin angiotensin aldosterone system regulates blood pressure in the long term
angiotensin II is a hormone that causes arteriolar constriction
total peripheral resistance increases
the hormone aldosterone increases sodium reabsorption
the plasma volume increases
describe how the hormone vasopressin regulates blood pressure in the long term
vasopressin is an antidiuretic hormone that causes arteriolar constriction
total peripheral resistance increases
water permeability of the collecting duct increases
plasma volume increases
describe how the atrial natriuretic factor regulates blood pressure in the long term
it is a hormone that causes arteriolar dilation
total peripheral resistance decreases
sodium excretion increases
blood volume therefore decreases
what is the kidneys response when blood pressure increases
extra water and salts are extracted into the urine, causing blood volume and pressure to fall, special nerve pathways mean the brain can also regulate urine production and hence influence blood pressure
what does activation of the renin angiotensin aldosterone system cause in relation to the kidneys
it causes sodium retention by the kidneys to increase
which leads to reduced water loss into the urine and therefore blood volume expansion
when does renin angiotensin aldosterone activation occur
during heart failure, which leads to fluid retention in the body
the renin angiotensin system regulates blood pressure and fluid balance in the body - how does this relate to the kidneys
when blood volume or sodium levels in the body are low, or blood potassium is high, cells in the kidney release the enzyme renin
what does the long term control of blood pressure resolve around
the control of plasma volume of the kidney
what is long term control blood pressure not mediated by
the arterial baroreflex
what are kidneys made up of
nephrons
what is the juxtaglomerular
it is denoting a group of structures secreting regulatory hormones into the arteriole which leads into a glomerulus in the kidney
where is renin secreted from
the juxtaglomerular kidney cells, which sense changes in renal perfusion pressure, via stretch receptors in the vascular walls
what also stimulates juxtaglomerular cells to release renin
signalling from the macula densa
what is the role of the angio tennis converting enzyme
it converts the hormone angiotensin 1 to the active vasoconstrictor angiotensin 2
what is the role of the antidiuretic hormone
it acts to maintain blood pressure, blood volume and tissue water content through controlling the amount of water and hence the concentration of urine excreted by the kidneys
how does the antidiuretic hormone help control blood pressure
by acting on the kidneys and the blood
what secretes the atrial natriuretic peptide hormone
myocytes of the cardiac atria
what does the atrial natriuretic peptide hormone promote
salt and water excretion and lowers blood pressure
what are the main physiological actions of natriuretic peptides
reduce arterial pressure by decreasing blood volume and systemic vascular resistance
what is Goldblatt kidney
it is a condition of the kidney in which a constriction of the renal artery causes renal ischaemia and the release of renin which would cause hypertension
what does long term control of blood pressure revolve around if it is not mediated by the arterial baroreflex
the control of plasma by the kidney, effectively how much plasma you are squeezing into the cardiovascular system
what does high plasma volume relate to
high blood pressure
what does low plasma volume relate to
low blood pressure
what are the 3 hormone systems that the kidney listens to
the renin angiotensin aldosterone system
the antidiuretic factor - the vasopressin hormone
the atrial and brain natriuretic peptides
state 5 functions of the kidneys
excretion of waste products maintenance of ion balance regulation of p regulation of osmolarity regulation of plasma volume
what is used to regulate mean arterial pressure in relation to the kidneys
it is the kidney’s regulation and control of plasma volume that is used to regulate mean arterial pressure
what does the control over sodium transport by the kidneys determine
the osmotic gradient
what does the control over the permeability of the collecting duct to water by the kidneys determine
whether the water is following to the osmotic gradient or not
what does the kidney modulation of sodium transport affect
the osmotic gradient
what does the kidneys making the collecting duct very permeable to water result in
lots of water reabsorption
little urine
conservation of plasma volume
what does the kidneys making the collecting duct very impermeable to water result in
little reabsorption
lots of urine
reduction in plasma volume
where does renin come from?
the juxtaglomerular of the kidney - the granule cells
state 3 things that trigger renin production
activation of sympathetic nerves to the juxtaglomerular apparatus
the renal baroreflex
decreased delivery of sodium and/or chlorine through the tubule
what is the role of renin
the enzyme converts inactive angiotensinogen to angiotensin 1,
angiotensin 1 is then converted by the angiotensin converting enzyme to angiotensin 2
what synthesises the antidiuretic hormone
the hypothalamus
what releases the antidiuretic hormone
the posterior pituitary
what does antidiuretic hormone release result in
decrease in blood volume
increase in osmolarity of interstitial fluid
circulating angiotensin II
what is the role of cardiopulmonary baroreceptors in relation to hormone release
they sense a decrease in blood pressure resulting in antidiuretic hormone release
what is the role of osmoreceptors in relation to hormone release
osmoreceptors in the hypothalamus sense an increase in osmolarity of the interstitial fluid resulting in antidiuretic hormone release
what is the role of the circulating angiotensin 2 hormone in relation to antidiuretic hormone release
the renin angiotensin aldosterone system results in the circulatory hormone angiotensin 2 which results in antidiuretic hormone release
what is the role of the antidiuretic hormone
increase in permeability of the collecting duct to water reduction of diuresis increase in plasma volume causes vasoconstriction increases in mean arterial pressure
what is another name for the antidiuretic hormone
vasopressin
where is the atrial natriuretic peptide produced and released from
myocardial cells in the atria
where is the brain natriuretic peptide produced and released from
myocardial cells in the ventricles
what triggers the release of atrial natriuretic peptides
increased distension of the atria
what triggers the release of brain natriuretic peptides
increased distension of ventricles
what is the roles of the atrial and brain natriuretic peptides
increase sodium excretion
inhibition of the release of renin
to act on medullary cardiovascular centres
to reduce mean arterial pressure
describe plasma volume in space
sustained residence in space fools the cardiopulmonary baroreceptors that there is high plasma volume, in space these cardiopulmonary baroreceptors trigger a reduction in plasma volume
state 5 drug treatments for hypertension
calcium channel blockers beta adrenoceptor antagonists thiazide diuretics angiotensin converting enzyme inhibitors angiotensin 2 antagonists
