What effect does constricting the efferent Arteriole have on the filtration process? During efferent arteriole constriction,
GFR is increased, but RPF is decreased, resulting in increased filtration fraction
. During a state of increased plasma protein concentration such as during multiple myeloma, GFR is decreased with no change in RPF, resulting in decreased FF.
What happens if you constrict the efferent arteriole?
Constriction of the efferent arterioles also
increases the vascular resistance so it reduces RBF
. The pressure within the glomerular capillaries may increase, however, because the flow is slowed by efferent arteriolar constriction.
How do afferent and efferent arterioles affect filtration?
What happens to the rate of kidney filtration when the efferent arterioles constrict quizlet?
What happens if both the Afferent & Efferent Arterioles are constricted? This would results in
a large increase in FF
(FF = GFR/RPF), since RPF will decrease greatly. GFR will remain constant. This results in the same amount of Sodium being filtered out, but more Sodium will be reabsorbed.
How would the filtration pressure change if the afferent arteriole is constricted?
Overall the constriction of the afferent arteriole
decreases both blood flow and filtration pressure
where as constricting the efferent arteriole decreases blood flow but increases filtration pressure.
What is the result of vasoconstriction of the efferent arteriole in the kidney?
The net result of efferent arteriolar constriction is an increased filtration fraction. The GFR most likely decreases because the RBF decreases, but the decrease in the GFR will not be proportionate because of the increase in glomerular capillary pressure.
What causes decreased glomerular filtration rate?
Glomerular filtration rate is a measure of functional renal mass. Reductions in GFR can occur with
primary renal disease, decreased renal perfusion, or obstructive renal disease
.
What causes an increase in glomerular filtration rate?
An increase in renal arterial pressure (or renal blood flow)
causes an increase in GFR. A reduction in renal arterial pressure (or renal blood flow) will have the opposite effect (1).
What is the function of the efferent arteriole?
The efferent arterioles form a convergence of the capillaries of the glomerulus, and
carry blood away from the glomerulus that has already been filtered
. They play an important role in maintaining the glomerular filtration rate despite fluctuations in blood pressure.
What constricts the efferent arteriole in the nephron quizlet?
Angiotension 2
is utilized in the kidney to cause the constriction of the efferent arteriole and therefore cause a decrease in RPF, an increase in GFR, and an overall increase in the filtration graction.
What is the effect of change in the radius of afferent and efferent arteriole on GFR?
Vasodilation in the afferent arteriole and vasconstriction in the efferent arteriole will increase blood flow (and hydrostatic pressure) in the glomerulus and will
increase GFR
. Conversely, vasoconstriction in the afferent arteriole and vasodilation in the efferent arteriole will decrease GFR.
Where would a vasoconstriction increase glomerular blood pressure quizlet?
Vasoconstriction of the afferent arteriole causes an increase in the
upstream pressure
and a decrease in glomerular pressure which decreases GFR, resulting in a decreased rate of urine formation.
Why does afferent arteriole constriction increased GFR?
Constricting the afferent arteriole reduces RBF
because the vascular resistance is increased
. This constriction also reduces the pressure downstream from the constriction, which reduces the GFR approximately proportionately.
What would happen if the arteriole that supplies blood to the glomerulus constricts?
If the arteriole that supplies blood to the glomerulus becomes constricted,
the glomerular filtration rate decreases
.
What are the factors affecting glomerular filtration?
We analyzed the factors that are thought to affect changes in GFR, such as age, sex, body mass index (BMI), preoperative GFR, preoperative creatinine level, operated side, presence of diabetes mellitus (DM), presence of hypertension (HTN), and duration of follow-up.
What happens if glomerular filtration rate decreases?
when gFR is below 60 for more than three months, this is
moderate-to- severe chronic kidney disease
. you may be referred to a nephrologist (kidney doctor) for evaluation and treatment. a gFR below 15 means kidney failure. if kidney failure occurs, dialysis or a kidney transplant will be needed to survive.
What factors affect glomerular filtration rate quizlet?
Factors that affect the glomerular filtration are
glomerular hydrostatic pressure, glomerular colloidal osmotic pressure, and the hydrostatic pressure in the Bowman’s capsule
. Glomerular hydrostatic pressure in the glomerulus is about 60 mmHg, which is higher than in other capillaries in the body (20-25 mmHg).
What increases filtration fraction?
Catecholamines (norepinephrine and epinephrine)
increase filtration fraction by vasoconstriction of afferent and efferent arterioles, possibly through activation of alpha-1 adrenergic receptors. Severe hemorrhage will also result in an increased filtration fraction.
What causes the constriction of afferent arterioles quizlet?
Increased Blood Pressure
leads to afferent arteriole vasoconstriction and efferent arteriole vasodilation. This leads to a decrease in glomerular hydrostatic pressure and therefore decrease in GFR. Decreased Blood Pressure leads to afferent arteriole vasodilation and efferent arteriole vasoconstriction.
What will vasoconstriction of these arterioles do to systemic blood pressure quizlet?
So the rise in pressure in the afferent arteriole of the glomerulus causes the arteriole to vasoconstrict. This would raise vascular resistance and
decrease the rise in glomerular hydrostatic pressure
that would otherwise occur from the increase in systemic blood pressure.
What is the first thing that happens when blood pressure decreases in the afferent arterioles of the kidney quizlet?
– When BP is low the afferent arteriole
relaxes/dilates
and allows more blood flow in the glomerulus to increase it.
What type of response by the afferent arterioles would you expect if blood pressure increased?
What type of response by the afferent arterioles would you expect if blood pressure increased?
The afferent arterioles would constrict
.
What effect will vasoconstriction of the afferent arteriole have on glomerular perfusion quizlet?
Vasoconstriction of the afferent arteriole
DECREASES glomerular blood flow
and the glomerular capillary pressure.
How does blood pressure affect glomerular filtration quizlet?
High systemic blood pressure would
increase GFR
, which would cause too much water and solutes to leave in the urine. The kidney responds by constricting the afferent arteriole to decrease blood flow (GFR).
Does vasoconstriction increase blood pressure?
Vasoconstriction reduces the volume or space inside affected blood vessels. When blood vessel volume is lowered, blood flow is also reduced. At the same time, the resistance or force of blood flow is raised. This causes higher blood pressure.
What causes constriction of efferent arteriole?
To compensate, the efferent arterioles constrict to a greater degree than the other arteries, in response to
increased levels of angiotensin II
. Pressure in glomerular capillaries is therefore maintained and glomerular filtration rate remains adequate.
Why is the efferent arteriole narrower?
Because it has a smaller diameter than the afferent arteriole
, it creates some resistance to blood flow, producing the back-up of blood in the glomerulus which creates higher pressure in the glomerular cavity.
What would happen if the arteriole that supplies blood to the glomerulus constricts?
If the arteriole that supplies blood to the glomerulus becomes constricted,
the glomerular filtration rate decreases
.
What happens to the efferent arteriole after it leaves the glomerulus?
Constriction of efferent arterioles as blood exits the glomerulus provides resistance to blood flow, preventing a pressure drop, which could not be achieved if blood were to flow into venules, which do not really constrict. The two arterioles
change in size to increase or decrease blood pressure in the glomerulus
.
