Lecture 3: Physiology of Kidney - Regulation of Osmolality Flashcards
1
Q
which hormone controls water regulation?
A
ADH (vasopressin) = argininine vasopressing (AVP)
2
Q
discuss the factors controlling ADH secretion
A
- primary control is plasma osmolarity: when the effective OP of the plasma increases, there is increased release of ADH from posterior pituitary.
- ECF volume also affects ADH secretion : increased ECF volume > decreased ADH secretion, decreased ECF volume > increased ADH secretion.
3
Q
what is the normal plasma osmolality?
A
280-290mOsm/kg
- it is regulated very precisely
4
Q
what is the role of urea in regulating osmolality?
A
- plays an important part in the production of concentrated urine.
- in anti-diuresis with high levels of ADH, urea is retained in order to save water and reinforce medullary gradient in region of thin ascending limb of LoH. Uraemia occurs.
5
Q
Which receptors monitor the return of blood to the heart and the ‘fullness’ of the circulation?
A
Low Pressure receptors are located in the L and R atria and great veins
6
Q
where are high P receptors located?
A
carotid and aortic arch baroreceptors
7
Q
A
8
Q
A
9
Q
A