Week 8 HRM Urinary Anatomy Flashcards
What does retroperitoneal mean?
Situated behind the peritoneum (the CT serous membrane that contains the abdominal contents) The kidneys are located retroperitoneal
What are the different components of the urinary system?
Kidneys, ureters, bladder and urethra
At what level of the spine are the kidneys located?
T12 - L3
Why is the the right kidney located slightly more inferiorly than the left?
The liver prevents the right kidney from ascending as far as the left
What are the various functions of the kidney?
Production, storage and excretion of urine Excretion of metabolic wastes Regulation of water levels and acid/base Regulation of arterial pressure Secretion of hormones (I.e. EPO, renin)
What are the 3 distinct regions of the kidney (as seen in a coronal cross section)?
Cortex
Medulla
Pelvis
What is the renal cortex? What structures are usually found there?
The outermost layer of the kidneys, which is covered by a fibrous capsule. Contains glomerulosa, PCT, DCT
What is the renal medulla and what structures are usually found there?
Medulla is located deep to the cortex and predominantly contains the Loop of Henle and the collecting ducts
What is the medial border of the kidney known as?
The hilum
What are the renal columns?
Columns of cortex that sit between the pyramids of medulla. These form the distinct lobes - usually 8.
What is the renal papilla?
The apex of the pyramids of medulla where urine travels out if the collecting ducts into papillary ducts
What are the minor and major calyces?
Where papillary ducts initially converge to form minor calyx. Where minor calyces merge leads to the formation of a major calyx
Why do the calyces contain smooth muscle?
To help move Urine along via peristalsis
When looking at a histological section - how can you differentiate between cortex and medulla?
The presence of glomerulosa. Areas where these are present are the cortex, and where absent is the medulla.
What major artery supplies the kidneys, and what large vessel has it branched from?
The renal artery - branched directly from the abdominal aorta
Why is the right renal artery longer than the left?
The aorta runs left of the midline, so the renal artery will travel further to reach the right kidney. The left renal vein will be longer as IVC is right of the midline
Where does the renal artery branch, and what is the branch called?
In the renal pelvis. Segmental arteries
Describe the blood flow into the kidneys from the segmental arteries through to the peri tubular capillaries and vasa recta:
Segmental –> interlobar –> arcuate –> interlobular –> afferent arteriole –> glomerulosa –> efferent arteriole –> peritubular and vasa recta
What is the function of the peritubular capillaries?
Associated with the convulsed tubules - allow for reabsorption
Where is the vasa recta capillaries located?
Associated with nephron loop
Which capillaries feed into the interlobular vein?
Peritubular and vasa recta
What is the only difference in the kidney venous system compared to the arterial system?
There are no segmental veins - straight from interlobar to renal vein
What percentage of cardiac output flows through the kidneys?
20-25%
What are the four components of a nephron?
Renal corpuscle (glomerulus + capsule)
Proximal convoluted tubule
Nephron loop (Henle)
Distal convoluted tubule
What are the 2 types of nephrons?
Cortical and juxtomedullary
Describe cortical nephron?
Contained mainly within the cortex, short nephron loops barely enter the medulla. Make up 70% of all glomeruli.