Inhibition of angiotensin converting enzyme by ramipril in serum and tissue of man.
Studies in animal models have indicated that ramipril is a potent inhibitor of angiotensin converting enzyme (ACE) in serum and tissue. In our study, the normal range of ACE activity and the inhibitory effect of short-term oral administration of ramipril on ACE activity in human serum and tissue samples of renal cortex, heart and blood vessels were determined. ACE activity in the renal cortex (125.2 +/- 11.5 nmol/mg per min) was greater than 600 times that of the heart (0.20 +/- 0.01 nmol/mg per min), greater than 500 times that of the veins (0.23 +/- 0.09 nmol/mg per min) and greater than 150 times that of the arteries (0.80 +/- 0.23 nmol/mg per min). ACE activity in the renal cortex and arteries 2 h after last dosing was almost completely inhibited by ramipril whereas ACE activity in the veins and heart was inhibited to a lesser extent. Our results demonstrate in man, for the first time, an inhibition of tissue ACE following short-term oral treatment with an ACE inhibitor.
Erman
A
A
Institute of Nephrology and Hypertension, Beilinson Medical Center, Petah Tikva, Israel.
Winkler
J
J
Chen-Gal
B
B
Rabinov
M
M
Zelykovski
A
A
Tadjer
S
S
Shmueli
J
J
Levi
E
E
Akbary
A
A
Rosenfeld
J B
JB
D000284:Administration, Oral; D000804:Angiotensin II / Q000097:blood; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D001643:Bridged Bicyclo Compounds / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007672:Kidney Cortex / Q000201:enzymology; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000201:enzymology; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D017257:Ramipril; D012016:Reference Values; D012083:Renin / Q000097:blood; D013514:Surgical Procedures, Operative; D013997:Time Factors
D000806:Angiotensin-Converting Enzyme Inhibitors; D001643:Bridged Bicyclo Compounds; D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A; D012083:Renin; D017257:Ramipril