Fig. 5.

Loss of effect of 2-MPPA with divided dosing. When the minimal-effect dose of oral daily 10 mg/kg 2-MPPA was distributed throughout the day by divided dosing as either 5 mg/kg BID or 3.3 mg/kg TID, the analgesic effect was lost. In each case, testing was conducted at 1 hour following the last 2-MPPA dose of the day. Statistical analyses were conducted with comparisons made to vehicle-treated animals. Significance criteria of P < 0.05 were used and are noted by an asterisk (*).