5/26 Flashcards
Portal Vein
- Formed by junction of splenic and SMA, also recieves blood from IMA
- Drains into liver and supplies oxygen and nutrients
- Generally maintains a higher BP than most veins
Porto-Caval Anastamoses
- In portal hypertension will enlarge to drain blood
- Superior and inferior rectal give hemerroids
- Left gastric and esophageal give varicies
- Periumbilical veins give caput medusa (inferior and superior epigastric)
- Retroperitoneal around kidney and liver
Esophageal Varicies
- Treat with beta blockers
- TIPS can be used (portocaval shunt in liver)
Portocaval shunt
Most commonly with Splenic vein and left renal vein
Budd Chiari
Thombosis of hepatic artery
- Often due to polycythemia
- Cause acute onset portal backup
Kidney
Ascends from sacral region
-Horeshoe can be trapped on IMA
Ureter
Mucular and innervated by PANS
- 3 tight spots
- At ureteropelvic junction
- As it crosses anteriorly to the common illiac
- As it flows into the bladder
- Also passes under gonadal veins (Water under the bridge)
Adrenals
- Sit atop kidneys
- Superior suprarenal artery from phrenic
- Middle suprarenal directly off aorta
- Inferior suprarenal from renal
Embryo
Mesenephros: contributes to the mesonephric duct and ureteric bud
- Ureteric bud become collecting system. UReter to collecting ducts
- Glomerulus from metenephric mesoderm
Aorta
-Runs through diaphragm at T12 with thoracic duct and azygous vein
-Phrenic
-Renal
-Suprarenal
Lumbar
Median sacral
ureteric
gonadal
-Bifurcates into common illiacs at L4
IVC
Runs on right side of aorta
-Crosses diaphragm through central tendon at T8
Thoracic DUct
Just posterior and to the right of the aorta
Preaortic Nodes
Collect Lymph from GI
Paraaortic
COllect lymph from gonads etc
Femoral Nerve
L2-L4
- Controls knee extensors and some hip flexion also skin on anterior and lateral leg
- Runs through the femoral triangel, outside the femoral sheath lateral to the artery and nerve
Paravertebral Ganglia
Sympathetic chains
-Carry preganglionic SANS
Prevertebral Ganglia
-Plexuses that carry cell bodies of post ganglionic SANS
Electron Acceptors
NAD and NADPH, use B3, niacin as cofactor/backbone
-NAD is for catabolic energy producing proceses and NADPH is for anabolic processes (HMP shunt)
Hexokinas
-Hexokinase is uqbiquitaly expresses in tissues and is a high affinity (low Km) and low capacity (low Vmax) enzyme that serves to trap glucose in periheral tissues under normal intrameal glucose conentrations
Glucokinase
- Present only in the liver and pancreatic beta cells
- Low affinity but high capacity
- Under high glucose levels such as post meal, large quantities are trapepd in liver and pancreas
- Glucose is trapped as glucose 6 phosphate which can run down glycolysis
- Glucose 1 phosphate is used for glycogen storage
Glycolysis
- Uses glucose and generats ATP, Pyruvate
- Subtrate level phosphorylation
- Activated by low energy levels (AMP/ADP) and inhibited by high energy levels (Citrate, and ATP)
- PFK-1 is the rate limiting enzyme
Glycolysis in the liver
In the liver glyoclysis can also be used as a starting point for the creation of other products
- Fructose 2,6 BPG is created by PFK-2 which is a positive feedback on PFK-1 and allows glycolysis to occur at a more rapid rate
- Glucagon reduces 2,6 BPG levels through Gs cAMP
- Insulin increases 2,6 BPG levels by decreasing cAMP
Pyruvate Kinase
- Catalyses conversion of Phosphoenolpyruvat to pyruvate
- Deficency leads to impaired energy production due to derranged NAD/NADH levels in RBC this leads to hemolysis
- Second most commor form of intravascular hemolytic anemia, no Hienz bodies will be present
Pyruvate Pathways
- Lactate
- Alanine
- OAA (GNG)
- Acetyl CoA (TCA)
Lactate dehydrogenase
Turns pyruvate into lactate and regenerates NAD from NADH.
- NAD is necessary for glycosysis to run, and NADH impairs glycosysis
- Seen in exercising skeletal muscle and glyocolytic tissues
- RBC, Lens, Cornea, Testes
ALT
Pyruvate turned into alanine,
- Liver specific
- Takes pyruvate prodcued in muscle and returns it as alanine
- Requries B6 (transaminase reaction)
Pyruvate Carboxylase
- Requires Biotin
- Turns pyruvate into OAA for GNG or TCA cycle
Pyruvate Dehydrogenase
- Pyruvate turned into Acetyl CoA
- Requires B1, B2, B3, B5 (CoA), and lipoic acid
- Allows for entry of acetyl Coa into TCA cycle
- Activated by exercise (Increase NAD/NADH ratio, Ca, ADP/AMP) all signs of energy usage
- ALpha ketoglutarate pathway of TCA cycle is very similar enzyme
PDH defects
- Viatmin Deficencies (thiamin) is very common
- Congential X linked presenting as neurologic dysfunction
- Treatement for congenital is to avoid glucose entry into TCA. Ketogenic diet (High in lysine and leucine only ketogenic AA’s)
- Arsenic poisoning impairs lipoic acid function and prevents PDH function. Rice water stools, abdominal pain, and breath smells like garlic
