Effects of KN-93 and Ro 25-6981 on oxaliplatin-induced increase in 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 KN-93 (50 nmol, i.t.) or Ro 25-6981 (300 nmol, i.t.) 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 KN-93 (A) and Ro 25-6981 (B) reduced oxaliplatin-induced increase in the spinal pCaMKII. Values are expressed as mean ± SEM. of 6-8 animals. *p < 0.05 compared with vehicle, †p < 0.05, ††p < 0.01 compared with oxaliplatin alone (one-way ANOVA followed by Tukey-Kramer post-hoc test).