Renal - Urinary System Flashcards
How much blood goes from the aorta to the kidneys?
20% of blood goes to the kidneys through the renal arteries
Kidney anatomy
Renal vein, renal artery, kidneys (renal capsule, cortex, renal columns between the renal pyramids, renal papillae at the apex of the pyramid, minor renal calyx, renal major calyx, pelvis) ureter
Vasa recta
Peritubular capillaries - efferent arteriole
What is the afferent arteriole sensitive to?
What is the efferent arteriole sensitive to?
Epinephrine
Angiotensin 2
What does epinephrine do to the afferent arteriole?
Epinephrine constricts the arteriole decreasing glomerular filtration rate (GFR)
Remember
At the glomerulus, there is one physiological physical activity.
Pure filtration. Pressure, fluid, and pore size.
Osmoregulation
Receptors are in the hypothalamus.
Hyperosmorality results in thirst and ADH release to dilute solutes more, trying to thing the blood out.
Volume regulation
baroreceptors in the macula densa.
When there is blood loss, then there is sympathetic activation and renin release from JGA
Where are most of the sodium reabsorbed in the kidney?
67% in the proximal tubule, 25% in the thick ascending loop of Henle
Is glucose, amino acid, bicarbonate reabsorbed into the bloodstream?
How much of it?
Almost all of the glucose, amino acid, and bicarbonate are reabsorbed in the proximal tubule
Where is calcium mostly reabsorbed?
It is reabsorbed throughout the whole nephron, but primarily in the proximal convoluted tubule
Where do you find the tri-cotransporter?
The NA-K-Cl transporter is found in the thick ascending loop of Henle
How does the potassium (K) reabsorption behave in the nephron?
Same as Sodium with the exception that in the distal convoluted tubule, it can be reabsorbed or excreted depending on the level of potassium in the blood
Remember
The liver produces angiotensinogen.
What is angiotensinogen cleaved to? by what?
Angiotensinogen is cleaved to angiotensin-I by renin
Who releases renin?
juxtaglomerular cells
What is ACE and what releases it?
The lung releases ACE. It stands for Angiotensin Converting Enzyme. It converts angiotensin I to Angiotensin II
What are the two activities of angiotensin 2?
Glomerular efferent arteriole constriction thus increasing GFR
and
ZOna glomerulosa activation of Aldosterone. It goes to the distal tubule and causes sodium reabsorption and potassium excretion.
Why do I want reabsorption of sodium?
Water follows sodium thus increasing the blood volume
When you drink water, what happens?
Decreases plasma osmolarity
Inhibits osmoreceptors in the anterior pituitary
Decreases secretion of ADH from the posterior pituitary
Decreases water permeability of late distal tubule and collecting duct
What organ does most transamination?
Liver, but the kidneys are also responsible for transamination
What is transamination?
Transamination is the process by which amino groups are removed from amino acids and transferred to acceptor keto-acids to generate the amino acid version of the keto-acid and the keto-acid version of the original amino acid
What do the transaminases use?
Vitamin B6
Urea cycle
Known this
where does it occur? Liver cell
What does it do? A way the liver takes two very dangerous metabolites (carbon dioxide and ammonia) combines them together forming urea that can go out into the blood and be filtered out from the tubular system
What part of the Urea Cycle happens in the mitochondria?
Carbon dioxide and ammonia are put together to form carbamoyl phosphate inside the mitochondria by carbamoyl phosphate synthase.
Carbamoyl synthase and L-ornithine is converted into L-citrulline by ornithine transcarbamoylase
What happens in the cytosol?
L-citrulline is converted into argininosuccinate and then into L-arginine and then arginase and then finally into urea.
Acute nephritis
Inflammation
Red cell casts, 1-2 weeks after recovery from sore throat, children 6-10 years, moderate proteinuria
IgA Nephropathy
Abnormal IgA
Damage to the cells in the glomerulus allowing blood to come in causes hematuria
Chronic GN
Usually in adults
Henoch-Schonlein Purpura
Purpuric skin lesion on the exterior surface of extremities and buttock
IgA precipitation after a respiratory infection, kids 3-8 years
Hematuria recurrences for years
Goodpasture’s syndrome
Rapid GN with auto-antibodies to the basement membrane
Young men who smoke
Death due to renal failure or lung hemorrhage
Type II antibody attack on the base membrane of glomerulus and alveoli so u have hematuria and hemoptysis together
Nephrotic syndrome
Heavy proteinuria, hypoalbuminemia, severe edema, hyperlipidemia
Kids due to primary kidney disease
Adults > SLE DM, amyloidosis, membranous GN most common cause
More in men, Immune complexes in the basement membrane, food allergy
Pyelonephritis
deadly
Affects tubules or interstitium
Ascending fecal flora, females, pregnancy, BPH, secondary to stasis or urine)
It is in the renal pelvis, infectious
It can kill you by seeding the blood and bacteria or by shutting your kidneys down.
Fever, dysuria, deadly
Hydronephrosis
finding
Dilation of the renal pelvis and calyces associates with progressive atrophy of the kidney due to obstruction of urine outflow
Urolithiasis
75% Ca oxalate, radiopaque (showup on x-ray)
25% radiolucent (no X-ray)
Proteus or Staph infection causes alkaline urine. increase crystal formation
Staghorn calculi = large obstructive stones in pelvis
Intrinsic causes of obstruction
renal calculi, strictures tumors, blood clots
Extrinsic causes of obstruction
Pregnancy, periureteral inflammation/salpingitis/peritonitis, tumors of the rectum, bladder prostate, ovaries, uterus
Cystitis
Bladder inflammation is usually due to infectious reasons
E.coli, urethral trauma, bacterial contamination
Can lead to Pyelonephritis, chronic cystitis
Interstitial cystitis
autoimmune disease
Usually women, chronic cystitis, inflammation of all layers of blader normal urinalysis
Suprapubic pain when the bladder is full which is relieved by voiding
Adenocarcinoma/Hyperphrenoma
Cigarette, pipe, and cigar smokers, upper kidney pole solitary, unilateral
Metastasize to lung and bone before sx appear
Painless hematuria
Wilm’s tumor
Nephroblastoma
Most common malignant kidney tumor in children
Large abdominal mass, painless hematuria, good prognosis with tx
aka nephroblastoma
Kidney disease of children
Rememeber
Painless hematuria is cancer until proven otherwise.
Most hematuria are painful
Benign Ureteric tumors
Polyps. May be too small to cause obstruction
Tumors of bladder
Risk factors; industrial solvents, cigarette smoking
Transitional cell tumors, benign papilloma; 90% transitional cell carcinoma, squamous cell carcinoma
Painless hematuria, HCG in urine is marker of aggressive tumor
