Kidney Structure and Function Flashcards
Which systemic diseases are associated with poor oral health?
Cardiovascular disease, rheumatoid arthritis, respiratory diseases, metabolic diseases, kidney diseases
What are the 2 main hypotheses linking periodontitis with systemic disease?
- Oral bacteria disseminate through oral cavity to bloodstream to distant sites where they contribute to pathology
- Oral diseases contribute to oral inflammation which in turn contributes to burden of systemic inflammation -> contributes to pathology elsewhere in the body
What are some of the shared risk factors between oral disease and systemic diseases?
Smoking, alcohol, stress, diet, economic status
What is the function of kidneys?
- Kidneys are excretory organs: process blood and rid the body of waste products of metabolism via urine
- Kidneys maintain homeostasis of fluid in the body
Describe the urinary system
Kidneys produce urine -> ureters convey urine -> bladder stores urine -> urethra carries urine out of the body
What is the indentation on the medial side of the kidney known as?
The hilum
Which artery delivers blood to the kidney?
Renal artery (from the aorta)
Which vein returns blood from the kidney to the heart?
Renal vein (to the vena cava)
What are the 3 distinct parts of the kidney?
Cortex: contains 85% of kidney tubules
Medulla: triangular structures; the site where urine is concentrated. Prevents excessive water loss
Pelvis: collection area for urine which is funnelled into ureter
How many litres of blood do the kidneys process per minute?
1.2 L of blood per minute
What structure provides the kidneys with protection?
Fat pads
Where do the kidneys lie with regards to the peritoneum?
They are retroperitoneal i.e. behind the peritoneum
Describe the vascular network in the kidneys
Renal artery -> segmental arteries -> lobar arteries -> interlobular arteries -> arcuate arteries -> interlobular arteries -> afferent arterioles -> glomerular capillaries -> efferent arterioles -> peritubular capillaries (vasa recta) -> interlobular veins
What is the basic functional unit of the kidney?
The nephron
What is the structure of the nephron optimally evolved to do?
Filter blood plasma and excrete waste products of metabolism in the urine
Where are the nephrons located?
Cortex
Juxtamedullary region
What is the purpose of the glomerulus and Bowman’s capsule?
Site of filtration, job is to remove products from the blood
What does the nephron consist of?
Renal corpuscle
Renal tubule
What is the renal corpuscle composed of?
The glomerulus and Bowman’s capsule
What is the renal tubule composed of?
Proximal Convoluted Tubule (PCT)
Loop of Henle
Distal Convoluted Tubule (DCT)
What is the purpose of the renal tubule?
Reabsorption and secretion (conservation/fine-tuning)
Describe the glomerulus
- A network of fine capillaries
- A single layer of endothelial cells resting on a basement membrane
- Fenestrated
- Enabled rapid filtration of blood plasma
- Surrounded by the Bowman’s capsule
Describe Bowman’s capsule
- A cup-like structure surrounding the glomerulus
- Parietal outer layer
- Visceral inner layer comprised of specialised epithelium (podocytes)
What are podocytes and what do they do?
- Podocytes are the specialised epithelium that the visceral inner layer surrounding the Bowman’s capsule is made of
- The long branched process (pedicels) of podocytes wrap around glomerulus capillaries
