ANP effects on filtration fraction/proximal reabsorption

[nguyen1025]

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From my understanding, angiotensin II raises the filtration fraction (constriction of efferent arteriole) which raises the osmotic pressure and lowers the hydrostatic pressure, thus causing an increase in proximal tubular reabsorption. So does ANP also do this since it raises the filtration fraction also? (Dilation afferent, constriction efferent). This all just seems a little counter intuitive to me.

 

[Ana90]

ANP and Ang II both increase filtration fraction but I think we should look at the reason why they do it:
ANP increases FF and at the same time increases Na+ and water excretion --> helps decrease the BP by natriuresis
Ang II increases FF to preserve the GFR. Also Ang II has the opposite effect of ANP on sodium reabsorption which increases BP.