E. Wang et al., ANGIOTENSINOGEN SYNTHESIS IN THE LIVER IS INDEPENDENT OF PHYSIOLOGICAL ESTROGEN-LEVELS, Biological & pharmaceutical bulletin, 18(1), 1995, pp. 122-125
We determined the physiological importance of endogenous estrogen in t
he regulation of angiotensinogen synthesis in the liver. The plasma le
vels of angiotensinogen and hepatic levels of angiotensinogen mRNA wer
e studied in the rat in comparison to those of T-kininogen, a plasma p
rotein whose synthesis in the liver is primarily estrogen-dependent. P
lasma levels of T-kininogen and hepatic levels of T-kininogen mRNA wer
e 3- and 2-fold higher in adult females, respectively, than in adult m
ales, whereas there were no sex differences in levels of either plasma
angiotensinogen or hepatic angiotensinogen mRNA. Ovariectomy in femal
e rats abolished the sex differences in the levels of plasma T-kininog
en and hepatic T-kininogen mRNA, but it did not affect those of plasma
angiotensinogen and hepatic angiotensinogen mRNA. These results sugge
st that, in contrast to T-kininogen, angiotensinogen synthesis in the
liver is unlikely to be controlled by endogenous levels of estrogen.