Renal Physiology Flashcards
________ is an enzyme produced by JG cells.
Renin is an enzyme produced by JG cells.
Inulin
Used to calculate GFR
Gold Standard by renal physiologists
Not used in veterinary medicine
Involves urine collection
There should never be _________ in the urine.
There should never be glucose in the urine.
The ____________ receives virtually all blood because it is where filtration and modification occur.
The cortex receives virtually all blood because it is where filtration and modification occur.
Water is unimpeded by the filtration apparatus thus is said to be __________.
Water is unimpeded by the filtration apparatus thus is said to be freely filterable.
Steroid effect on prostaglandins
Blocks PLA2 enzyme activity
Increased Creatinine primarily caused by
Decreased H2O in the blood
Decreased filtration by the kidney
Parasympathetic nervous system _______ heart rate.
Parasympathetic nervous system decreases heart rate.
Why do we calculate GFR?
- Acute Renal Disease
- Chart progression of Chronic Renal Disease
Water is not reabsorbed at the ___________.
Water is not reabsorbed at the ascending loop of henle.
______________: events in the renal tubules influence the RBF and GFR.
Tubuloglomerular Feedback: events in the renal tubules influence the RBF and GFR.
Relationship between plasma [creatinine] and GFR
Increased plasma [creatinine] = decreased GFR
SDMA
Used for earlier diagnosis of CKD
Put into blood stream all of the time by all cells during protein degredation
Excreted exclusively by kidney
___________: cells of the mascula densa maintain RBF by monitoring [Na+, K+ and Cl-]
Humoral Response: cells of the mascula densa maintain RBF by monitoring [Na+, K+ and Cl-]
Increased CHP due to systemic pressure = __________ GFR.
Increased CHP due to systemic pressure = increased GFR.
__________ causes increased PGC, increased GFR and decreased RBF.
Constriction of Efferent Arteriole causes increased PGC, increased GFR and decreased RBF.
Great increase in CHP due to efferent arteriole tone = ____________ GFR.
Great increase in CHP due to efferent arteriole tone = decreased GFR.
_________________
Increase in resistance decreases flow (occlusion)
Increased CHP due to afferent arteriole tone = ___________ GFR.
Increased CHP due to afferent arteriole tone = increased GFR.
Increased [Na+, K+, Cl-] tells the mascula densa that there is _________ GFR.
Increased [Na+, K+, Cl-] tells the mascula densa that there is increased GFR.
Podocytes are found within the viseral epithelium of ___________.
Podocytes are found within the viseral epithelium of Bowman’s Capsule.
What are the two types of nephrons in the kidney?
Cortical and Juxtamedullary
_________ is the most important parameter in determination of normal renal function
GFR is the most important parameter in determination of normal renal function
Juxtaglomerular (JG) cells are found in the _____________ of the kidney.
Juxtaglomerular (JG) cells are found in the afferent arteriole of the kidney.
NSAIDs effect on prostaglandins
Indescriminant COX blocker
Decrease blood flow to the kidney
Cause GI ulcer
Decrease blood clotting
Layers of the “filter”
- Fenestrations
- Basement Membrane
- Filtration slits
Under normal conditions ________ is essentially zero.
Under normal conditions BSCOP is essentially zero.
Amount of plasma in should __________ the amount of plasma out of the kidney (in a normally hydrated animal.)
Amount of plasma in should equal the amount of plasma out of the kidney (in a normally hydrated animal.)
Describe the stretch reflex
Stimulus > Afferent Neuron > Brain > Preganglionic Neuron > Postganglionic Neuron > Effector Organ
Urine is produced when
All the time
___________ responds to decreased [Ca++] to maintain overall Ca++ homeostasis.
Parathyroid Hormone (PTH) responds to decreased [Ca++] to maintain overall Ca++ homeostasis.
Describe the vascular network of the nephron
Afferent Arteriole → Glomerulus → Efferent Arteriole → 1. Peritubular Capillaries or 2. Vasa Recta
Regulation and maintenance of plasma concentration within homeostatic norms is acheived by
Filtration
Secretion
Reabsorption
Excretion
Kidney produces ________ to combat the constant influence of vasoconstrictors.
Kidney produces prostaglandins to combat the constant influence of vasoconstrictors.
The urinary system is composed of _________, _________, ___________, and ________.
The urinary system is composed of kidneys, Ureters, Urinary bladder, and Urethra.
Describe the synthesis of creatine
- Kidney: AA1 + AA2 = Dipeptide
- Dipeptide released into bloodstream
- Taken up by Liver: Dipeptide + AA3 = Creatine
- Creatine released into the blood stream
- Taken up by Skeletal Muscle: Creatine + Phosphate = Creatine-P
- Creatine-P spontaneously falls apart to form Creatinine (waste molecule)
Iohexol
Contrasting agent that can be used to calcualte GFR
Single injection (and a few timed blood draws)
Take plotted results and calculate AUC
25 hydroxycholecalciferol is converted to 1,25 dihydroxycholecalciferol (calcitriol) by the enzyme _____________.
25 hydroxycholecalciferol is converted to 1,25 dihydroxycholecalciferol (calcitriol) by the enzyme 1 alpha hydroxylase.
Renal Autoregulation mechanisms
Direct Myogenic Response
Humoral Response
Increased blood pressure is due to:
- Vasoconstriction
- Stroke Volume
- Heart Rate
- Volume of Fluid
______ is virtually unchanged in the glomerulus, has an overal higher pressure than other capillaries.
CHP is virtually unchanged in the glomerulus, has an overal higher pressure than other capillaries.
Freely filterable substances have a filterability coefficient of _______.
Freely filterable substances have a filterability coefficient of 1.0.
When skeletal muscle is at rest what happens to creatine?
ATP is invested into creatinine for “storage” forming creatine-P
Functions of the kidney
Regulate and maintain plasma concentration
Regulate and maintain blood volume and pressure
Calcitriol
Catabolism
Gluconeogenesis
Synthesis of Erythropoietin
Synthesis of Creatine
Effects of decreased blood pressure on vessels includes
Vasoconstriction where needed