Figure 3

Adenosine production is impaired in spinal nociceptive circuits of Pap^-/- , Nt5e^-/- and dKO mice. FSCV was used to measure adenosine production at subsecond resolution. (A) Illustration depicting the placement of the carbon fiber microelectrode and the micropipette for pressure ejection of AMP into lamina II (transverse section shown to highlight anatomy; however, sagittal sections were used for these experiments). (B) Normalized cyclic voltammograms obtained for adenosine in physiological buffer (in vitro, dashed trace) and during pressure ejection of AMP into lamina II of a WT slice (solid trace; taken from the dashed vertical line in panel C). (C-F) Color plots for the 1 s pressure ejection of 100 μM AMP into lamina II of (C) WT, (D) Pap^-/-, (E) Nt5e^-/-, and (F) dKO slices at pH 7.4. (G) Current extracted at 1.0 V from the dashed horizontal lines in (C-F), converted to concentration of adenosine and plotted versus time. (H) Peak adenosine production following pressure ejection of AMP into lamina II at pH 7.4 (n = 5 for each genotype). (I) Current extracted at 1.0 V from representative experiments performed at pH 5.6. (J) Peak adenosine production following pressure ejection of AMP into lamina II at pH 5.6 (n = 5 for each genotype). (H, J) One way ANOVAs with post-hoc tests were used to compare each genotype to WT and to compare between genotypes. *P < 0.05, **P < 0.005. Data presented as means ± s.e.m.