Figure 7.

Influence of the vanilloid VR1 receptor antagonist capsazepine (a) and the histamine H₃ receptor antagonist clobenpropit (b) on the inhibition of the electrically induced increase in basal DBP by LPS (4 mg kg⁻¹) in pithed and vagotomized rats. The preganglionic sympathetic nerve fibers were subjected to up to four periods (S₁–S₄) of ES (1 Hz, 1 ms, 50 V for 10 s). Capsazepine 1 μmol kg⁻¹ (CAPZ, filled bar) was administered 2 min before S₁ and 2 min before S₃; clobenpropit 0.1 μmol kg⁻¹ (filled squares) was injected 5 min before S₁. For further details of the experimental protocol, see Figure 1. Both for animals exposed and not exposed (open bar, open squares) to the antagonists, the ratios S₂/S₁, S₃/S₁ and S₄/S₁ for the increase in DBP obtained in the presence of LPS were expressed as percentages of the corresponding ratios obtained in animals treated with the vehicle for LPS (control). With respect to capsazepine, only the S₃/S₁ ratio was determined. Means±s.e.m. of 4–8 rats. ^**P<0.01, ^***P<0.001 compared to the corresponding control.