Anatomy Flashcards
what level do the kidneys lie at in the retroperitoneum?
either side of the vertebral column at level of T12-L3
which kidney is lower?
the right kidney - pushed down by the liver
what are the layers of the kidney?
fibrous outer capsule outer cortex (where all the glomeruli lie) inner medulla (the tubules of the nephron dip in and out)
what does a nephron consist of?
glomerulus proximal tubule loop of Henle distal tubule collecting duct
where do the renal arteries come from?
branch off the abdominal aorta, divides into smaller branches until arterial blood reaches the glomerulus
blood to the nephron?
afferent glomerular arterioles arise from interlobular branch arteries to supply the glomerular capillary tuft
drains into the efferent glomerular arterioles
what happens to the blood in the efferent arterioles?
the efferent arterioles from the outer cortical glomeruli drain into the peritubular capillary network within the renal cortex & then into increasingly large and more proximal branches of the renal vein
what happens to blood in the inner juxtamedullary glomeruli?
it passes the vasa recta in the medulla and returns via the cortex to renal veins which drain into the inferior vena cava
what is the innervation of the renal capsule and ureters?
T10-T12 and L1 nerve roots
renal pain is felt over the corresponding dermatomes
what is the path of glomerular filtrate to urine?
nephrons collecting duct minor calyx major calyx renal pelvis ureter bladder urethra
how is glomerular filtration influenced by the arterioles?
the contractile tone of the afferent and efferent arterioles affect the rate of glomerular filtration
e.g. efferent vasoconstriction increases the rate of glomerular filtration
what is the juxtaglomerular apparatus?
it regulates flow and filtration in each individual nephron
columnar epithelium in the macula densa sense the concentration of tubular fluid sodium (higher filtrate flow = more delivered sodium) which trigger adenosine mediated vasoconstriction of the afferent arteriole to drop glomerular filtration
the juxtaglomerular cells secrete renin, able to induce aldosterone release - allows apparatus to monitor flow drop GFR when needed and retain salt for fluid balance
What does upper urinary tract consist of?
Kidneys
What does lower urinary tract consist of?
Ureters
Bladder
Urethra
Functional unit of kideny?
Nephron
What does nephron consist of?
Glomerulus
Tubule (Proximal, convoluted, loop of H, Distal convoluted & CD)
What hormone do kidneys produce?
Erythropoietin
What does erythropoietin do?
Forms RBCs and renin
-Convert Vitamin D to it active 1,25-dihydroxyvitamin D
Where is kidney in abdomen?
Retroperitoneal
What lies superior to kidney?
Adrenal glands
What is anterior to the right kidney?
Duodenum
Ascending colon
Liver
What is anterior to left kidney?
Stomach
Pancreas
Spleen
Descending colon
Posterior to kidneys?
Diaphragm Psoas Transverse abdominis 12th rib 12th subcostal nerve
What does hilum of each kidney have?
Renal vein & renal artery & renal pelvis
Journey for renal arterial circulation?
Aorta | Renal artery | Segmental artery | Interlobar artery | Arcuate artery | Cortical radiate artery | Afferent artery | Glomerulus | Efferent arteriole | Capillaries & vasa recta
Journey of venous drainage for kidneys?
Peritubular | Cortical radiate vein | Arcuate vein | Interlobar vein | Renal vein | IVC
Where does fluid move from out of capillaries?
Enters nephron as glomerular filtrate which is processed by kidney to become urine
What do juxtaglomerular glomeruli give rise to?
Efferent arterioles
These descend into
Medulla and divide into hairpin shaped capillaries & form vasa recta
What vessels have a role in countercurrent exchange?
Capillaries
What are kidneys innervated by?
Autonomic nervous system
What type of autonomic innervation?
Sympathetic
Each kidney is innervated by?
Renal plexus which recieves:
- Post-ganglionic fibres from coeliac ganglia
- Aorticorenal ganglia
- Lower splanchnic nerves
Also contains afferent sensory nerve fibres = activation of these cause diuresis
What happens with increased sympathetic activity?
Renal artery constriction | Decreased renal blood flow | Decreased GFR + Na+ & H20 reabsorption
