Upper Urinary Tract Flashcards
What are the 4 main components of the urinary system?
kidneys
ureters
bladder
urethra
Where are the kidneys located in the body?
cranial/superior abdomen
where in the body is the bladder located?
pelvic cavity
through what area of the body is urine voided?
perineal area
In humans what is found in the perineal area?
pelvic floor
What is the main/significant role of the kidneys?
filtration of toxins from the blood
what is the function of ureters?
transport urine to the bladder by peristalsis
what is the function of the bladder?
stores urine until it is convenient to void
what is the function of the urethra?
transports urine out of the body, forms part of the male reproductive tract
what are the 3 main functions of the kidney?
process blood plasma, maintain homeostatic balance, remove urea
what can kidney failure lead to?
homeostatic imbalance and death
what is urea a waste product of?
protein metabolism
During kidney transplant is the diseased kidney removed?
no, remains in the abdomen and the new kidney is implanted inferior to it
What leaves the kidney at the hilus (hilum)?
blood vessels, nerves, ureters
What is provided to the kidney by perirenal fat?
protection from: pressure exerted by other organs, shock and trauma
What 3 domestic species have the ‘kidney bean’ shaped kidneys?
dogs, cats, sheep
How can a feline kidney be differentiated from canine?
there are prominent external veins on the feline kidney
is there much perirenal fat on canine and feline kidneys?
no - unless they are obese
how much perirenal fat is present in sheep kidneys?
lots!
How do pig kidneys differ in shape from the classic ‘kidney bean’ shape?
dorsoventrally flattened so not as rounded
How do ox kidneys differ from other species?
lobed and left kidney is twisted and close to the midline
why is the left kidney in the ox close to the midline?
as the rumen develops it pushes the left kidney towards the midline (dorsally)
are all kidneys lobed at some point during embryo/foetal stages?
yes
what is each lobe of the ox kidney separated by?
deep fissures and connective tissue
what shape is the equine left kidney?
kidney bean
what shape is the equine right kidney?
love heart
which of the equine kidneys is more cranial?
right
what part of the abdominal cavity are kidneys located within?
cranial/superior abdominal cavity
What abdominal wall are the kidneys located on?
posterior abdominal wall
what does retroperitoneum mean?
behind peritoneum
what vertebra are kidneys in line with?
T12 to L2
Which kidney is more superior in the abdomen in humans?
left
what shape are human kidneys?
kidney bean
In most domestic species which kidney is more cranial?
right
between which vertebrae is the right kidney located in most domestic species?
L1-L2
between which vertebrae is the left kidney located in most domestic species?
L3-L4
Why is the right kidney often very difficult/impossible to palpate in domestic species?
its very close to the liver
In what species are kidneys at the same level?
pigs
In the ox and cat what makes the left kidney more mobile?
“less” retroperitoneal
What bones are the kidneys located beneath?
ribs
What muscles are the kidneys very closely associated with?
Quadratus lumborum and Psoas major
what structures are transmitted out of the hilus in humans?
renal vein, artery, nerve and ureter
where do the paired renal arteries arise from?
aorta
where do the paired renal veins drain into?
inferior or caudal vena cava
What is the functional unit of the kidney?
nephron
approximately how many nephrons are there per kidney?
1 million
what is the glomerulus made up of?
network of fenestrated capillaries
what occurs in the glomerulus?
ultrafiltrate is formed from blood
what does the Bowman’s capsule surround?
glomerulus
describe the flow from glomerulus to collecting duct
glomerulus - Bowman’s capsule - proximal convoluted tubule - loop of Henle - distal convoluted tubule - collecting duct
What is reabsorbed into the blood at the proximal convoluted tubule?
60-80% of filtered water and sodium and normally all nutrients
What happens at the distal convoluted tubule?
fine tuning of water and salt balance
what is the fine tuning of water and salt balance at distal convoluted tubules controlled by?
aldosterone and antidiuretic hormone
what is final urine volume in a human?
1-2 litres per day
what is the outer layer of the kidney called?
capsule
what is the next layer of the kidney deep to the capsule?
cortex
what gives the cortex it’s granular appearance?
renal corpuscles and proximal and distal convoluted tubules
what two components make up renal corpuscles?
Bowman’s capsule and glomerulus
Where are renal columns found?
in between medulla (renal pyramids)
what is the apex of the medulla/renal pyramid called?
renal papillae
what parts of the nephron are found in the medulla?
Loops of Henle and collecting ducts
how does the medulla appear?
striated
Where does urine exit the medulla and collecting duct system?
renal papillae
Where do minor calyxes attach?
to papillae
where do major calyxes occur?
minor calyxes join to from major calyxes
how is the pelvis of the kidney formed?
fusion of major calyxes
what part of the kidney does the ureter drain from?
pelvis
What is a renal lobe?
renal pyramid with own cortex
What are the 3 types of kidney internal structure?
multipyramidal, multipapillate, unipyramidal
Describe the internal structure of the multipyramidal kidney
divided cortex, divided medulla, calyxes, no pelvis, drain into secondary ureters and then ureter
what do calyxes drain in multipyramidal kidneys?
individual lobes
describe the internal structure of a multipapillate kidney?
fused cortex, divided medulla, calyxes, pelvis
In multipapillate kidneys is there an individual cortex for each pyramid?
no
in what two species may multipyramidal kidneys be found?
ox and dolphin
in what two species may multipapillate kidneys be found?
pig and human
describe the internal structure of a unipyramidal kidney
fused cortex, fused medulla, fused calyxes, pelvis
are there any individual pyramids in unipyramidal kidneys?
no
what 4 species can unipyramidal kidneys be found?
dog, cat, horse and sheep
in all kidney types does the performance and function remain the same?
yes
how can animals in hot habitats conserve water?
able to markedly concentrate urine
what does the length of the loop of Henle correlate with?
the animals ability to concentrate urine
what does a longer loop of Henle lead to? :
more concentrated urine
in kangaroo rats what structure do the loops of Henle extend into?
ureter
What are the camels adaptions to water scarcity?
increased drinking capacity (RBC can swell up to 200x without haemolysis)
conservation of metabolic water
can survive dehydration with good grazing
minimal sweat glands
long loops of Henle
Why can cats manage kidney disease so well?
as their kidneys are very efficient
how long are ureters in humans?
25cm long
what are the ureters made of?
smooth muscle lined with uroepithelium
what sort of epithelium is uroepithelium?
transitional
how is urine moved into the bladder?
by peristalsis
why must urine be moved from the kidneys to the bladder by peristalsis?
as pressure in the bladder is greater than pressure in the kidneys
in humans, what arteries do ureters recruit branches from in order to supply them?
renal, gonadal, common illiac and internal illiac
what ligament are ureters partly located within in the bitch?
broad ligament
how do ureters enter the bladder?
at an oblique angle
What is the broad ligament closely associated with?
uterine horns
what are kidney stones formed from?
aggregate formed from salt crystals
how many sets of successive kidneys develop in the mammalian embryo?
3
what are the names of the 3 successive kidney types in the mammalian embryo?
pronephros
mesenephros
metenephros
When does the pronephros develop?
early, near the neck
what develops alongside the pronephros?
pronephric duct
one the pronephros disappears what happens to the pronephric duct?
remains and forms part of the mesenephric duct
what develops after the pronephros?
mesenephros
what develops after the mesenephros?
metenephros
what is the metenephros the precursor to?
adult kidney
what structures form near the metenephros?
uretric bud and cloaca
what will the uretric bud go on to form?
ureter, calyxes, collecting duct and collecting tubule
what is the function of cloaca?
hindgut region where embryo waste is expelled
what embryological germ layer is the kidney formed from?
intermediate mesoderm
what part of the embryo do the successive stages of the kidney develop in?
nephric ridge
is the pronephron formed more cranially or caudally?
cranially
what animals have pronephros as adult kidneys?
lampreys and hag fishes
what animals have a mesenephros as an adult kidneys
fish and amphibians
what does the mesonephric duct form in adult males?
ductus defrens
what animals have a metenephric kidney s an adult kidney?
reptiles, birds and mammals
describe the development from pronephros to metenephros
pronephros develops in nephric ridge along with pronephric duct. pronephros starts to disappear, replaced with mesonephros. Mesonephric duct joins to pronephric duct. Metenephros forms from mesenphros and the metenephric duct becomes the ureter.
what are 2 developmental issues of the kidneys?
horseshoe kidney, unilateral renal hypoplasia
what are some potential developmental issues of the ureters?
bifid renal pelvis (two present on one side of the body) and bifid ureter (two on one kidney)
in the embryo how many different anatomically and chronologically discrete locations does the kidney develop in?
3
