Fig. 4. Glutamate (Glu) release in spinal synaptosomes from lumbar spinal cord tissue ipsilateral (  filled squares ) or contralateral (  open circles ) to spinal nerve ligation by 20 μm capsaicin alone (control) or in the presence of 1–1,000 nm adenosine. Each  symbol represents the mean ± SE of eight observations. *  P < 0.05, compared with control by two-way analysis of variance.  P > 0.05, F value 0.314, no statistical difference in lumbar spinal tissue between contralateral and ipsilateral to spinal nerve ligation.