Figure 1

Radiolabelled pregabalin detection. The harvested tissues are displayed on the X axis for the systemic (A, D) and for nervous system tissues (B, C, E, F). Systemic (A) or nervous system (B, C) pregabalin concentrations are demonstrated for 73-74 hours after intrathecal (white bars) or intranasal (black bars) or near nerve (gray bars) pregabalin delivery. Note that the 73 and 74 hour timepoints were analyzed together for these timepoints early after completion of 72 hours of delivery. At 77 hours, at 5 hours after the most recent intranasal delivery, systemic (D), brain (E), and cord (F) pregabalin concentrations started to fall. Near nerve delivery led to sciatic nerve pregabalin concentrations several fold higher than achieved with either intrathecal or intranasal delivery, but near nerve delivery was not associated with detectable pregabalin elsewhere. Significant differences between concentrations achieved with intervention methods were determined by matched ANOVA testing, with * indicating significant differences (p < 0.05) between the intranasal or intrathecal pregabalin delivery and saline delivery techniques for each tissue and respective delivery method. The doses provided through either intranasal or intrathecal delivery were selected to be similar to doses of pregabalin used in later subexperiments [n = 4-6 rats in each rat cohort for each time point]. Note that data are not shown for locations other than the sciatic nerve for near nerve pregabalin delivery, as other locations had no measureable pregabalin found.