Vol. 277, Issue 5, R1261-R1267, November 1999
Different modulation of aromatase activity in frog testis in
vitro by ACE and ANG II
Antonino
Miano,
Anna
Gobbetti,
Massimo
Zerani,
Luana
Quassinti,
Ennio
Maccari,
Oretta
Murri,
Domenico
Amici, and
Massimo
Bramucci
Department of Molecular, Cellular, and Animal Biology, University of
Camerino, I-62032 Camerino, Italy
The aim of
the present research was to study the role of angiotensin-converting
enzyme (ACE) and ANG II in amphibian (Rana esculenta) testicular steroidogenesis and
prostaglandin production. Hormonal effects of ACE, ACE inhibitors,
synthetic bullfrog ANG I, and
[Val5]ANG II were
determined in frog testis of prereproductive period. Production of
17
-estradiol, progesterone, androgens, and
PGE2 and
PGF2
was determined by
incubating frog testes with ACE (2.5 mU/ml), captopril (0.1 mM),
lisinopril (0.1 mM),
[Val5]ANG II (1 µM), and synthetic bullfrog ANG I (1 µM). The analysis of the data showed
an independent modulation of
17-estradiol and androgen production
by ACE and ANG II. The ACE pathway caused a decrease of
17-estradiol production and an
increase of androgen production in frog testes; on the other hand, the
ANG II pathway increased
17-estradiol production and
decreased androgen production. The determination of testicular
aromatase activity showed a positive regulation by ANG II and a
negative regulation by ACE. As for prostaglandin production, only ANG
II influenced PGF2. These results suggest a new physiological role of ACE and ANG II in modulating steroidogenesis and prostaglandin production.
17-estradiol; progesterone; androgens; prostaglandin
E2; prostaglandin
F2; angiotensin-converting enzyme
