A hemodynamic feature of chronic sinoaortic
-denervated (SAD)
rats is the increase in blood pressure variability (BPV) without
significant change
s in the average level of blood pressure (BP).
The current study
was designed to
investigate the changes in BP
V- shaped waves (V waves) in SAD rats. Sprague
-Dawley (SD)
rats were divided into
2 groups: SAD rats and sham
-operated
rats (n=13
). Hemodynamics measurements were obtained in
conscious, freely moving rats, four weeks after sinoaortic
denervation or sham operation. V wave indices were evaluated in
rats in both conscious and quiet states.
Additionally, n
ormal and
high BPV was simulate
d by the production of V waves with
different amplitudes. The results showed that the V wave
amplitude was dramatically increased, with a significantly
prolonged duration and reduced frequency in SAD rats
. V wave
BPV in SAD
rats
was significantly increased
, though BP remained
unchanged. The twenty
-four hour BPV in all rats was positively
correlated with amplitude, duration time and V wave BPV and
negatively correlated with frequency. The systolic
BP spectral
powers in the low frequency range (0.38
-0.45
Hz)
were
significantly reduced in the V waves of SAD rats. Moreover, there
was a remarkable increase in mean BPV and a normal mean BP
after simulating high BPV in SAD rats
. The
se results
suggest that
enhancement of V waves might be a waveform character of BP in
SAD rats in both the conscious and quiet states. These types of
V waves appear to be related to a depression of sympathetic
regulation of BP induced by sinoaortic
denervation.