Fig. 3.

Vasoreactivity studies for PPT with and without NOS-inhibition using l-NAME. PPT was added to the organ bath 10 min prior to PE. l-NAME was added 40 min prior to PE. A: force is expressed as %change from baseline. B and C: force is expressed as %change from PE-precontraction. PPT rapidly and significantly decreased PE-mediated vasoconstriction. This effect was attenuated in the presence of l-NAME (A). l-NAME also attenuated PPT vasodilator effects in the presence of ACh (B). In contrast, endothelium-independent vasorelaxation was not affected by NOS-inhibition (C). SNP, sodium nitroprusside. N = 3–7/group. †P < 0.05 vs. vehicle; ††P < 0.001 vs. vehicle; *P < 0.001 vs. PPT + l-NAME; #P < 0.001 vs. l-NAME; ‡P < 0.05 vs. PPT + l-NAME.