ILA 9 Renal Flashcards
What is the role of atrial naturetic peptides (ANPs)
They act on the renal collecting tubules to promote Na+ excretion
What secretes ANP
Atrial myocytes
What is ANP released in response to
Atrial stretch due to elevated atrial pressure and blood volume, e.g cardiac failure
What 4 things does ANP cause
Increased glomerular filtration rate
Increased Na excretion
Inhibition of release of vasoconstrictors eg. Aldosterone and angiotensin II
Decrease in bp
What does aldosterone act on and what’s its effect
Distal collecting duct to cause an increase in the uptake of Na
Does the overall effect of aldosterone increase of decrease bp
The increase in Na causes an increase in bp
How does aldosterone’s pattern of release mirror cortisol
Both have a diurnal pattern of release
What secretes aldosterone
Adrenal cortex
What is renal clearance
Volume of plasma cleared of that molecule per minute
A molecule that has a renal clearance of 125 mls/min has been…..
Filtered and passed into the urine unchanged
Eg insukin
A molecule that has a renal clearance of 80 mls/ min has been…..
Filtered and reabsorbed
Eg urea
A molecule that has a renal clearance of 650-700 mls/min has been
Filtered and actively secreted
How is urine transported to the bladder
Peristaltic action of the ureters
Describe the control of the detrusor muscle
Under control of the autonomic system with some voluntary control
What is the anatomical location of the kidneys
Retroperitoneal
What secretes renin
Juxtaglomerular cells (JGC)
Renin is released in response to…..
Stimulation of beta adrenergic receptors on the JGC
How does renin convert angiotensinogen to angiotensin I
Removing a short amino acid chain
The macula densa stimulate renin release in response to…..
Changes in Na+ delivery to the distal tubules
How much of the cardiac output passes through the kidneys
20%
What lines the ureter
Transitional epithelium
What is the mechanism of chronic renal failure
CRF causes a reduction in erythropoietin production
Erythropoietin is a glycoprotein cytokine that stimulates erythropoiesis in the bone marrow
