AJP - Renal Physiology, Vol 249, Issue 4 542-F545, Copyright © 1985 by American Physiological Society
Renal prostanoids after unclipping the denervated one-kidney, one-clip hypertensive rat
R. Vandongen, H. McGowan, H. Anderson and A. Barden
The contribution of the renal nerves in maintaining blood pressure and
modulating renal prostanoid synthesis was examined in established (less
than 8 wk in duration) one-kidney, one-clip (1K,1C) hypertension in the
rat. Systolic blood pressure was measured for 7 days after renal
denervation, at which time the renal artery clip was removed.
Twenty-four-hour urinary excretion of PGE2 and 6-keto-PGF1 alpha (stable
degradation product of PGI2) was determined before and after denervation
and unclipping. Compared with sham-denervated rats, denervation (n = 15)
resulted in a small but significant fall in blood pressure (from 216 +/- 4
to 182 +/- 4 mmHg after 48 h) and an increase in urinary 6-keto-PGF1 alpha
(from 31 +/- 4 to 43 +/- 5 ng/24 h after 24 h). There was no change in PGE2
excretion. Seven days after surgery, blood pressures were similar in
denervated (202 +/- 4 mmHg) and sham-denervated (211 +/- 5 mmHg) rats and
fell to a similar extent 24 h after unclipping (142 +/- 3 and 147 +/- 4
mmHg, respectively). Urinary 6-keto-PGF1 alpha increased from 25 +/- 5 to
74 +/- 11 in denervated and 21 +/- 2 to 72 +/- 9 ng/24 h in sham-denervated
rats in the 24 h after unclipping. PGE2 excretion increased approximately
twofold over this period. These findings indicate that the renal nerves
have only a minor role in established hypertension in the 1K,1C rat and
that the reversal of hypertension and stimulation of renal prostanoid
synthesis following unclipping is not dependent on neural mechanisms.
