Urinary Week 3 Flashcards
How many kidneys do fish have?
1
What is the difference between the function of gill in freshwater vs saltwater fish?
In freshwater the fill actively take up NaCl whereas in saltwater they excrete it
what are the 2 nephron types in avian species?
reptile type- no loop of henle, cant concentrate
Mammalian type- longer, loop of henle
What controls tubular water permeability?
Arginine vasotocin
Where are the salt glands and what is there purpose?
Supraorbital, secreting excess salt
What is the major difference in bladder anatomy in snakes vs chelonians?
Snakes have no bladder, chelonians have a bladder and accessory bladders
Which hormones are involved in the RAAS system
Angiotensin II and aldosterone
Which extrinsic mechanisms kick in under acute haemorrhage?
Sympathetic nervous system- vasoconstriction
Angiotensin II- vasoconstrict
Endothelin- vasoconstrict
Prostaglandins, NO
What happens when you eat a meal high in salt?
Increase ECF volume, increased blood pressure, increased flow to the kidneys, suppresses renin, decreases salt reabsorption, decreases ECF, decreases pressure
What is the action of angiotensin II?
Insertion of Na+ channels in renal tubules in proximal tubule, thick ascending limb and in collecting duct
By what mechanism does urine move along the ureter?
Peristalsis via locally regulated smooth muscle
Which urethral sphincter is made of striated muscle fibre?
External urethral sphincter
What are the central connections to micturition
Pons and cerebral cortex, some at cerebellum
What is the detrusor reflex?
When increased vesicular pressure with filling achieves the threshold resulting in contraction of the detrusor muscle
What is the effect of alpha adrenergic blocker on micturition?
Decrease sphincter tone
What is dysuria?
Difficult or painful passage of urine
What is pollakuria?
Increased frequency of urinations
What is enuresis?
Unconscious leakage of urine during sleep
What are the symptoms of a lower motor neuron bladder?
Absent voluntary micturition
Atonic bladder
Atonic urethral sphincters
Absent detrusor reflex
Where do loop diuretics act?
Na+K+2Cl- symporter in thick ascending limb of the loop of henle, inhibits sodium and chloride reabsorption
How do potassium sparing diuretics work?
Directly blocking the epithelial sodium channel thereby inhibiting sodium reabsorption
How long does it take for spironolacton to have effect?
2-3 days
How do osmotic diuretics work?
Presence leads to an increase in osmolarity of the filtrate so water is retained in the urine
What maintains calcium concentratin?
Parathyroid hormone and Vitamin D
