Effect of trifluoperazine on oxaliplatin-induced increase of spinal CaMKII phosphorylation. Rats were treated with oxaliplatin (4 mg/kg, i.p.) twice a week for 4 weeks (days 1, 2, 8, 9, 15, 16, 22 and 23). The lumbar sections (L4-6) of the spinal cord were quickly removed at 30 min after administration of trifluoperazine (0.3 mg/kg, p.o.) on day 25. CaMKII phosphorylation (pCaMKII) in the lumbar sections of the spinal cord was determined by Western blotting. An increase of pCaMKII was found in the spinal cord of oxaliplatin-treated rats. Acute treatment with trifluoperazine reduced oxaliplatin-induced increase in the spinal pCaMKII. Values are expressed as mean ± SEM. of 6-7 animals. *p < 0.05 compared with vehicle, ††p < 0.01 compared with oxaliplatin alone by Tukey-Kramer post-hoc test.