Physiology Renal Book Flashcards
Normal intravesical pressure
3cmH2O
Nerves of micturition
Para- S2-4- increase contraction of detrusor and decrease internal urethral sphincter
Also via pudendal to external urethral
Symp- via hypogastric plexus L1-2-decrease detrusor and increase internal urethral
Cause of cell uptake of potassium
Insulin
B adrenergic
Theophylline
The process of Na reabsorption in kidneys
70% in PCT relying on ATP pump
Descending limb- some passive addition
Ascending- active absorption- furosemide inhibits
DCT- thiazide inhibits
The descending limb is permeable to
Urea, Water
Where is the majority of bicarbonate reabsorbed
PCT
Where is the majority of carbonic anhydrase located and fucntion
PCT
To converts carbonic acid into water and CO2 allowing absorption
Where does the majority of H reabsorption occur
DCT
Location of Na within body
5% intracellular
50% extracellular
45% within bone
Stimulation and function of ANP
Secreted by atria following distention
Increases water and Na secretion
Complication of TURP and tx
Low Na- causing restlessness, headache, resp distress and hypoxia, pul/cerebral oedema
Furosemide and fluid restriction
Anion gap calculation
Na+K-Cl-HCO3
BB effect on renin
Inhibits
Due to B1 receptors in JXGA stimualtion
Effect of ANP on kidneys
Increase GFR by dilation of arterioles
Inhibit Na reabsorption
Reduced renin secretion
Composition of juxtaglomerular apparatus
Macula densa- found in the region where PCT is in direct contact with glomerulus. Macula densa senses the sodium chloride concentration in the filtrate
Juxtaglomerular cells- e found at the walls of the afferent arteriole. The primary function of juxtaglomerular cells is to produce renin, in response to prostaglandins produced by macula densa cells.
Mesangial extraglomerula cell
Function of angiotensin 2
Increase sympathetic activity
Aldosterone release
Arteriole vasoconstriction
ADH secretion
Location of production of hormones in adrenal gland
Zona glomerulus- aldosterone
Fasiculata- cortisol
Reticularis- sex hormones
Medulla- adrenaline and noradrenaline
Best substance for measuring renal clearance
Inulin
Pros of creatinine use for eGFR
Released at constant rate
Endogenous
Not reabsorbed (slightly secreted)
Normal anion gap
10-18
Autoregulation of GFR with change in BP
Increase in BP- vasoconstriction of afferent to decrease GFR
How much of the CO do the kidneys receive
25%
