Fig. 6.
Incubation with sodium nitrite does not affect the vascular contraction induced by angiotensin II or by the PKC activator PDBu. Panel A shows the vasoconstriction induced by angiotensin II (10−10 to 10−7 mol/l) in aortic ring preparations. The aortic rings were preincubated for 5 min with sodium nitrite 1 mmol/l (or vehicle) in the bath chambers and washed out extensively with modified Krebs salt solution. After eliminating residual sodium nitrite from the bath chambers, concentration-response curves in response to angiotensin II were constructed. Panels B and C show the corresponding pD2 values (the negative logarithm of the concentration producing half maximum effect) and maximum effect, respectively. Panel D shows the vasoconstriction induced by the PKC activator PDBu (10−9 to 10−5 mol/l) in aortic ring preparations preincubated with sodium nitrite (or vehicle) as described above. Panels E and F show the corresponding pD2 values (the negative logarithm of the concentration producing half maximum effect) and maximum effect, respectively. Data are shown as mean ± S.E.M. (n = 6/group).