How Does Adh Affect The Collection Duct Flashcards
What does ADH stand for?
Antidiuretic hormone
Also known as vasopressin.
What is the primary role of ADH?
Controls water reabsorption in the collecting duct and distal convoluted tubule (DCT)
It is crucial for osmoregulation.
Which part of the brain detects changes in blood water potential?
Hypothalamus
What happens when blood water potential decreases?
Hypothalamus sends nerve impulses to the posterior pituitary gland
Where is ADH released from?
Posterior pituitary gland
How does ADH affect the collecting duct?
Increases permeability to water
What do ADH receptors activate in the collecting duct cells?
cAMP (a second messenger system)
What do vesicles containing aquaporins do when cAMP is activated?
Move to the cell membrane
What is the effect of increased aquaporins on the collecting duct?
More permeable to water
How does water move out of the collecting duct?
By osmosis
What is the result of more water being reabsorbed into the blood?
Concentrated urine
What happens to ADH levels during dehydration?
More ADH released
Fill in the blank: If water potential is too low, ADH leads to _______.
More water reabsorbed
What effect does low ADH levels have on urine?
More urine, more dilute
What role does the loop of Henle play in osmoregulation?
Maintains a low water potential in the medulla
True or False: The loop of Henle uses a countercurrent multiplier system.
True
Which system restores water balance in response to ADH?
Negative feedback system
What happens to aquaporin levels when the body is hydrated?
Fewer aquaporins
What is the effect of ADH on urine concentration during dehydration?
Low volume, concentrated
What is the consequence of increased collecting duct permeability?
More water reabsorbed into blood
Summarize the effect of dehydration on ADH and urine.
High ADH levels lead to concentrated urine
Summarize the effect of hydration on ADH and urine.
Low ADH levels lead to dilute urine
