Macroscopic anatomy of the urinary tract

Identify what has been lebelled here

• RK = right kidney

• LK = left idney

• B = bladder

• P = prostate

• Sp = spleen

• U = ureter

• Ur = urinary bladder

what is the product from the kidneys?

• urine

Describe the location of the kidneys within the abdomen

• retro-peritoneal, dorsal abdomen

• in ventral lumbar region with limited mobility

• right kidney is most cranial

• left kidney is most mobile

in which species is the kidney more mobile?

• cats

In which species is the right kidney not the most cranial kidney?

• pig

Identify the kidenys

Remember right is more cranial than left

what is the cranial landmark of the left kidney?

• greater curvature of the stomach

what does the left kidney attach to dorsomedially

• spleen

what may the left kidney be in contact with cranially?

• left limb of pancreas

what is attached to the left kidney medially?

• left adrenal gland

what does the left kidney attach to caudally?

• small intestine and descending colon

in females what may the left kidney be in contact with?

• ovary

what does the right kidney attach to cranially?

• renal fossa of caudate lobe of the liver

what is the right kidney attached to caudally?

• caudal vena cava

what is the right kidney attached to dorsolaterally?

• right adrenal gland

what is ventral to the right kidney?

• descending duodenum

what is ventrally and medially to the right kidney?

• right pancreatic limb

in females, what is attached to the right kidney?

• ovary

what do we need to retract surgically to see the left kidney?

• mesocolon

what do we ened to retract on the RHS of the abdomen surgically to visualise the right kidney?

• mesoduodenum

state the 3 basic components of the kidney

1. outer fibrous capsule

2. renal cortex

3. renal medulla

what is the renal hilus?

• area where the artery, vein and ureter enter/exit the kidney

what makes up a renal lobe?

• cortex + pyramid + papilla

where do blood vessels travel in the kidney/

• in the renal columns

what is each minor calyx fixed to?

• one papilla

in which species is the kidney ‘bean shaped’

• dog

• cat

• sheep

• goat

when cutting sagitally through a kidney, what structure may be identifiable?

• renal crest

describe the shape of renal kidneys in the horse

• more triangular in shape

• Right = ‘heart’ shaped

• left = ‘pyramidal’ - J shaped (VD view)

describe the shape of porcine kidneys

• long and flat

• more rectangular

describe the structure of the bovine kidney

• reniculate

which other species share a structure similar to that of a bovine kidney?

• acquatic mammals

• bears

  • elephants

what are the 2 regions of the cortex?

• external

  • internal - juxtamedullary

what is found in the cortex

• glomeruli

• convoluted tubules

what do we find in the medulla?

• loops of henle and collecting ducts

what are the parts of the renal medulla?

• outer part = base of pyramid

• inner part = renal papilla - only collecting ducts

describe unilobar kidneys

• single renal lobe

• single pyramid

• single papilla

which species have a unilobar kidney?

• rodents and lagomorphs

what kind of kidney do other animals, not rodents and lagomorphs have?

• multilobar kidney

describe the structure of the kidney in cows, elephants, bears and acquatic mammals;

1. cortex?

2. medulla?

3. lobes?

4. renal papillae?

5. calyx?

6. pelvis?

7. surface appearance?

1. separate

2. separate

3. multiple

4. multiple

5. multiple

6. no

7. lobulated - reniculate

describe the appearance of the pig and primate kidney:

1. cortex?

2. medulla?

3. lobes/pyramids?

4. renal papillae?

5. calyx?

6. pelvis?

7. surface appearance?

1. fused

2. separate

3. obvious ones

4. multiple

5. multiple

6. branched

7. smooth

Describe the anatomy of the kidney of the dog, cat, sheep and horse:

1. cortex?

2. medulla?

3. lobes?

4. pyramids?

5. renal papillae?

6. calyx?

7. pelvis?

8. surface appearance?

1. fused

2. fused

3. internally, yes

4. partially merged

5. merge to form renal crest

6. no

7. single one

8. smooth

Fill in

• globate

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• globate

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• globate

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• reniculate

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• unilobar

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• multilobar

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• single

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• fused

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• multiple

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• single

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• fused

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• multiple

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• single

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• fused into renal crest

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• multiple

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• no

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• multiple

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• major and minor

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• yes

Fill in

• no

what are minor calyx?

• where the urine first drains into from the medullary pyramids

what is a major calyx?

• where 2-3 minor calyx drain into a bigger calyx = major calyx

what do pigs and primates have, which aren’t major/minor calyx?

• renal pelvis - where the major calices drain into → ureter

in dogs, cat, sheep and horses, what structure do they have instead of calyx?

• renale crest - as the medullary cones are fused

• renal crest → renal pelvis

what do we call it in dogs and cats where the medullary pyramids are fused?

• renal crest

what do we call the space the urine drains into in dogs and cats

• renal pelvis

where is the renal pelvis located in dogs and cats

• in the renal sinus

what intersting feature does the renal pelvis have ina dog and a cat we may visualise on radiography?

• folds in its renal pelvis - called recesses

what are recesses

• large, irregular structure with broad processes on the renal pelvis

in which species do we find recesses/

• single lobe speices

how many recesses are there in the horse?

• two

what are calyces?

• small, irregular structure with short stems ending in dilated regions - pigs and primates

do cattle have a pelvis?

• no

what do cattle have instead of a pelvis?

• proximal ureter leading to multiple calyces

What species is this?

• cattle

What species is this

• pigs and people

What animals have this structure?

• carnivores

• sheep

  • goats

describe the basic flow of blood in the kidney

1. hilus

2. cortex

3. medulla

4. cortex

5. hilus

what additional system do we find around the nephrons?

• intra-renal portal system

Name the vessels working from largest to smallest

• aorta → renal a.

• interlobar artery and vein

• arcuate artery and vein

• interlobulary artery and vein

  • renal vein → CVC

state the renal blood flow circuit

1. aorta

2. renal artery

3. inter-lobar artery

4. arcuate artery

5. inter-lobular artery

6. afferent glomerular arteriole

7. glomerulus

8. efferent glomerular arteriole

9. inter-lobular vein

10. arcuate vein

11. inter-lobar vein

12. renal vein

13. caudal vena cava

describ the blood supply to the:

1. cortical glomeruli

2. juxtamedullary glomeruli

1. peritubular capillaries

2. peritubular capillaries (cortex) and vasa recta (medulla)

describe the venous outflow from a nephron

• venules drain peritubular capillaries and vasa recta → arcuate or interlobulary veins

  • DO NOT RE-ENTER BOWMAN’S CAPSUL

what supplies the blood to the PCT+DCT?

• peritubular capillaries

what supplies the loop of henle blood?

• vasa recta

what is the role of the peritubular capillaries and vasa recta?

• resorb many solutes

why do the medulla and cortex need different blood supplies?

• the solutes resorbed in the PCT and DCT would negatively impact the medullary tissue

what are end arteries?

• arteries which don’t have a back-up supply/anastamoses with other vessels

what is the consequence of an end artery if it’s damaged?

• the area of tissue it supplies will die and necrose off

what do all carnivores have an additional of in terms of blood supply?

• cortical venous drainage

what is a cortical venous drainage in carnivores?

• drain twoards hilum of kidney without going towards renal medulla

describe the cortical venous drainage in dogs

• veins flow through cortex to hilum and join renal vein - anastamose with deep cortical veins

describe the cortical venous drainage in cats

• subcapsulr veins run over cortex - distinctive feature - do not anastamose, unlike dog ones

What species kideny is this

• cat

describe the wall of the bladder

1. mucous membrane

2. urolethium

3. tight junctions

4. lamina propria

5. muscular layer

6. adventitia

why does the baldder wall have tight junctions between its cells

• to protect against urine

What has been demonstrated here by contrast?

• abnormal ureters near bladder - likely due to a prostate tumour (near the neck of the bladder!)

what are the two portions of the ureters?

• abdominal

• pelvic