Hormone Regulation Flashcards
What ways can urine volume be increased?
disease, increased H2O consumption,high bp, diaretics
Disease affecting high urine output
Glomerular nephritis, diabetes mellitus, diabetes incipides
Types of diabetes incipides
① injury to hypothalamus
② x-lined recessive mutation for v2 receptor
③ autosomal dominance for mutated aquaporeins
Treatments for diabetes insipidus
Desmopressin: synthetic analogue of vasopressin (adh)
Low sodium diet: decrease osmotic pressure in nephron
Increase water consumption: replace water lost in urination
Diuretics
Chemicals increasing crime output by effecting homeostatic regulation mechanisms
Types of diuretics (3)
Alcohol, caffire, medicinal diuretics
Alcohol
Inhibits ADA secretion from poster purtuitory gland
What is a hangover
Body dehydration by alcohol inhibition of adh
Caffeine
① Blocks Na channels improximal and distal convoluted tubules increasing hypertonicity of filtrate
- osmotic pressure decreases in pertitublar capillary causing water to remain in nephron
- less water absorbed so more out
② caffeine increases blood pressure (vasoconstrictor)
- increase glomerular filtration rate → increase rate of urination
Medicinal diuretics who are prescribed
High blood pressure, congestive heart failure, chronic renal failure
Excess fluid inblood and body tissues strains the heart making breathing difficult
Examples of medicinal diuretics
Mersalyl acid and spironolactone
Mersalyl acid
Mercurial diuretic a non-competitive inhibitor of aquaporin
When banded water channel closes, despite ads secretion so the DCT and Cd are impermeable
Spironoloactone
Competitive inhibitor of aldosterone
When bonded to aldosterone receptors on distal convoluted tubal cells → aldosterone doesn’t bind → Na ion channel not formed so it remains in heparin and increases osmotic pressure preventing water reabsorption → increased urine
High blood pressure
Increases glomerular pressure and glomerular filtration rate → increase urination
Cold weather in children
Thermorgulatory mechanisms constrict blood vessels increasing glomerular filtration rate → urire rate
How does adrenaline affect urination rate?
When adrenal glands secrete adrenaline it causes blood vessels to constrict increasing blood pressure → glomerular filtration → urine rate
Glomerular nephritis
Damage to glomerular capillaries (hypertension) increases glomerular pore size
Which allows RBC and plasma proteas to pass into filtrate → increase osmotic pressure and inhibited water reabsorption
Increased water lossinurine
Diabetes mellitus (type 2)
Insult not made or not recognized → glucose remains in blood
Glucose is reabsorbed in proximal convoluted tubule but carrier proteas for glucose is limited so when there is an increased amount it remains
High concentration ofglucose → increased osmotic pressure in nephron
Less water reabsorbed and excreted as urine
Diabetes insipidus- hypothalamus injury
Head injury causes damage to hypothalamus where add is produced
50, ash doesn’t get produced when dehydrated so distal Ct and Ct are impermeable
Plus 15% =20 L
Diabetes insipidus- x linked recessive mutation gene to v2 receptor
If ads can’t bind to mutated v2 receptor → protein kinase A cannot make aquaporein vesicles and don’t fuse with apical cell membranes of distal and collecting
Affect the male species
Diabetes instpides- autosomal dominant to aquaporein gene
Mutation = change to shape, size, charge
Without aquaporein channels distal CT and CD are impermeable to h20
Is the body better at regulating low or high blood pressure
Low bp using homeostatic mechanisms
Dilation = lower blood volume = lower blood pressure
Vasocontriction= increase blood volume = increase blood pressure
Angiotensin bp regulation
① when there is low bp
-Bleeding /blood loss
- Excessive Heat (loss blood volume due to sweating)
- dilation of blood vessels (alcohol vasodilator)
② pressure receptors juxtaglomerular apparatus near kidney secrete renin enzyme (regulator)
③ angiotensinogen → renin → angiotensin ( efferent pathway mediator to etfectors)
④ angrotension binds causes blood vessels to constrict
⑤ higher bp
Aldosterone Na regulation
1 when low bp and angiotensin is secreted
② binds to adrenal cortex receptors (kidney on top)
③ adrenal cortex excretes aldosterone hormone (efferent pathway to effectors)
④ with aldosterone genes of Na carrier proteins are transcribed in distal ct to make more Na carrier proteins
⑤ increase Na reabsorption, decrease osmotic pressure in heparin, increase h20 absorption
⑥ increase bp due to increased plasma volume