Figure 1. Effect of norepinephrine administration on capsaicin-evoked release of immunoreactive calcitonin gene-related peptide (iCGRP) from in vitro-superfused dental pulp. Bovine dental pulp was collected, sliced into 200-µm² slices, and superfused with oxygenated Krebs’ buffer. Levels of iCGRP released from dental pulp were collected over a seven-minute fraction and measured by radioimmunoassay. Norepinephrine (3 nM) or vehicle was administered from fractions 0–28 min, and capsaicin (10 µM) was administered to all chambers over a 21- to 28-minute period. Data are calculated as % increase over baseline 100 x (peak release - baseline)/baseline. Error bars are SEM. **p < 0.01 vs. vehicle. N = 6/group.