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Physiology II
Renal Mechanisms for Controlling ECF Osmolality

(Ch. 5, Koeppen and Stanton)

Understand what normal plasma osmolality is, and the reason why changes in the amount of water alone in the plasma has dramatic effects on plasma osmolality, and therefore health.

Get clear in your mind the basic concept that changes in the amount of water alone in the plasma affects the plasma osmolality, while changes in the amounts of plasma Na+ alone affects the volume of plasma, and how these changes in turn affect blood pressure.

Understand what ADH is, where it comes from, and how and where it works in the kidney to regulate the amount of water that is allowed into the urine.

Understand the major factors in the plasma dynamics which cause both an increase and decrease in the release of ADH from the hypothalamus.

Understand what happens to the thirst mechanism when changes in plasma osmolality occur, and the importance of this.

Get clear in your mind what the concentration and volume of the urine is expected to be in a normal individual with high plasma levels of ADH, and with low plasma levels of ADH.


Last Updated 04/10/00 12:27:13 PM
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