Hypertension, Vol 7, 879-885, Copyright © 1985 by American Heart Association
RR Notvest and EJ Zambraski
The baroreceptor reflex control of renal nerve activity was examined in
seven normotensive and 14 deoxycorticosterone acetate-treated anesthetized
Yucatan miniature swine. Pressor responses evoked by the administration of
phenylephrine were used to assess reflex control. The mean absolute
threshold for inhibition of renal nerve activity was higher but not
significantly different between the deoxycorticosterone acetate-treated and
normotensive group. However, the mean relative threshold for inhibition of
renal nerve activity was significantly greater in the deoxycorticosterone
acetate-treated group (p less than 0.05). Responses from five
deoxycorticosterone acetate-treated and five normotensive swine were used
to examine the time course of the baroreflex inhibition of renal nerve
activity. During the initial rise in pressure the percent inhibition of
renal nerve activity was similar for the two groups. During the recovery
phase of the response, renal nerve activity in the deoxycorticosterone
acetate-treated group returned to baseline while renal nerve activity
remained attenuated below baseline in the normotensive group. The gain of
the reflex was significantly lower in the deoxycorticosterone
acetate-treated group compared with the control group (p less than 0.05).
The results of this study clearly indicate that baroreceptor reflex control
of renal nerve activity is altered in anesthetized deoxycorticosterone
acetate-treated hypertensive swine.
ARTICLES
Baroreflex control of renal sympathetic nerve activity in hypertensive miniature swine