Term
| What proteins does aldosterone stimulate the synthesis of? |
|
Definition
| Na/K ATPase pumps and Na/H exchangers |
|
|
Term
| Are Na/K ATPase pumps on the basolateral or apical membrane? |
|
Definition
| Basolateral – they pump Na out of the cells into the blood and bring K into the cells |
|
|
Term
| Are Na/H exchangers on the basolateral or apical membrane? |
|
Definition
| Apical – they exchange H+ into the tubule for Na+ into the cells |
|
|
Term
| Where does aldosterone have its greatest effect? |
|
Definition
| Reabsorption of sodium from the collecting duct |
|
|
Term
| What organs participate in the “5 organ” concert? |
|
Definition
| Kidney, liver, lung, adrenals, brain |
|
|
Term
| How do high levels of ACTH affect aldosterone? |
|
Definition
| High levels of ACTH increases aldosterone sensitivity to ATII and ATIII |
|
|
Term
|
Definition
| Tubuloglomerular feedback = regulation of a snGFR – this works via the JGA |
|
|
Term
| Over what range of pressures can GFR and RPF be regulated? |
|
Definition
|
|
Term
| How is an increase in intrarenal AT-II different than an increase in plasma AT-II? |
|
Definition
Plasma AT-II increases the contraction of afferent arterioles.
Intrarenal AT-II increases renal prostaglandin synthesis and release which causes relaxation of the afferent arteriole, overriding the effects of renal sympathetic nerve activity and plasma AT-II. |
|
|
Term
| What are the two major stimuli for ADH release? |
|
Definition
| Increase in plasma osmolarity and decrease in plasma volume |
|
|
Term
| Where are increases in plasma osmolarity sensed? |
|
Definition
| Osmoreceptors in the hypothalamus |
|
|
Term
| Where are decreases in plasma volume sensed? |
|
Definition
|
|
Term
| Where do osmoreceptors in the brain and cardiac atrial receptors project? |
|
Definition
| To the supraoptic and periventricular neurons which signal a release of ADH from the posterior pituitary. |
|
|
Term
| Which would trigger an ADH release first – a decrease in plasma volume or an increase in plasma osmolarity? |
|
Definition
| A decrease in plasma osmolarity because you have to go down about 10% plasma volume before a signal is triggered |
|
|
Term
| Where does ADH allow UREA permeability in the nephron? |
|
Definition
| Only in the lower collecting duct |
|
|
Term
| Where does ADH allow WATER permeability in the nephron? |
|
Definition
| In the entire collecting duct |
|
|
