Reciprocal Regulation of
Angiotensin Converting Enzyme and Neutral Endopeptidase in Rats
with Experimental Hypertension
JONGUN LEE
Department of Physiology, Chonnam National University Medical
School, Gwangju, Republic of Korea
Received February 25, 2003
Accepted Septemebr 23, 2003
Summary
Angiotensin I is a substrate for both the angiotensin converting
enzyme (ACE) and neutral endopeptidase 24.11 (NEP). The present
study examined the hypothesis that a high ACE expression is
associated with a low NEP activity. Male Sprague-Dawley rats had
two-kidney, one-clip (2K1C), NG-nitro-L-arginine methyl ester
(L-NAME) or deoxycorticosterone acetate (DOCA)-salt
hypertension, which were either angiotensin-dependent or
-independent. The expression of ACE and NEP mRNA was determined
in the thoracic aorta by a reverse transcription-polymerase
chain reaction. The catalytic activity of NEP was measured by
fluorometry. The expression of ACE was increased in 2K1C and
L-NAME hypertension, and decreased in DOCA-salt hypertension.
Conversely, the expression of NEP was decreased in 2K1C and
L-NAME hypertension, and increased in DOCA-salt hypertension.
The catalytic activity of NEP was altered similarly as its
expression. These results suggest that ACE expression is
inversely related to vascular NEP activity in certain forms of
hypertension.
Key words
Angiotensin-converting enzyme • Neutral endopeptidase
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