Efferent arteriole Afferent arteriole

Filtrate is forced through holes in glomerular capillary walls Glomerular Filtration Filtrate is forced through holes in glomerular capillary walls

Glomerular capillary: Internal endothelial cell sieve; external covering of podocytes

Varying resistance to flow controls filtration pressure

A-II A-II vasoconstricts predominantly the efferent arteriole Vasoconstriction increases glomerular pressure and filtration Afferent arteriole

A-II ACEI and ARBs remove A-II effect: efferent arteriole dilates Glomerular pressure and filtration decrease a little Afferent arteriole

ACEI reduces glomerular pressure and filtration of albumin  remission of nephrotic syndrome due to diabetic nephropathy eGFR Ramipril 5mg daily

Glomerular pressure and filtration decrease slowly Low blood pressure and vascular disease reduce pressure and flow into glomerulus Efferent arteriole A-II A-II Glomerular pressure and filtration decrease slowly Afferent arteriole

A-II ACEI and ARBs remove A-II effect: efferent arteriole dilates Glomerular pressure and filtration suddenly decrease a lot Afferent arteriole

eGFR -----lisinopril----- --ramipril--

ACEI and ARBs can be good or bad 1997-2008: ACEI/ARB reduce pressure and slow decline in GFR. Gradual vascular narrowing 2008: Critical drop in GFR - ACEI/ARB stopped. GFR recovers 2009: Increased glomerular pressure causes proteinuria eGFR ACEI and ARBs can be good or bad for kidney function lisinopril 20mg od irbesartan 75mg od Stop both Proteinuria +++ K+ = 7.5 Urea = 22