Figure 6.

Atenolol (1 mg kg⁻¹; i.v.) pretreated spontaneously breathing anaesthetized rabbits: histograms showing the changes in the size of the aortic nerve-evoked (80 Hz decrease in mean arterial pressure (MAP), increase in R-R interval and decrease in renal sympathetic nerve activity (RNA) before (control, left columns), at 7.5 (middle columns) and 22.5 min (right columns) following administration of saline (20 μl, i.c.; n=5), buspirone (200 μg kg⁻¹; i.c.; n=5), buspirone (200 μg kg⁻¹, i.c.) following pretreatment with WAY-100635 (100 μg kg⁻¹; i.v.; n=5), buspirone (200 μg kg⁻¹; i.v.; n=4) and WAY-100635 (100 μg kg⁻¹; i.c.; n=6). It should be noted that WAY-100635 i.c. study has been carried out using a different protocol to the rest of the data and thus time after drugs is different (1.5 and 11.5 min). Each column shows the mean change in the size of the reflex and bars show s.e.mean. Changes caused by the treatment have been compared with time-matched controls. *P<0.05, **P<0.01 compared to saline #P<0.05, ##P<0.01 compared to buspirone i.c. alone.