Question

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How would drinking large amounts of pure water alone affect the secretion of ADH? How would it affect the secretion of Aldosterone? What would the net effect be on urine production?

Answer 1

Drinking of large amount of pure amount will result in decreased osmolarity and increased blood volume.
This will result in suppression of osmoreceptors in the hypothalamus which inhibits ADH release from the posterior pituitary. This causes increased renal excretion of water.
The increase in blood volume also causes inhibition of aldosterone from the adrenal gland which results in reduced reabsorption of sodium and water from kidneys.
Decreased release of ADH as well as aldosterone results in reduced water reabsorption from renal tubules and increased urinary output.