Effects of nociceptin/orphanin FQ on rats with cathartic colon

Figure 1 Effects of OFQ (10^-9-10^-6mol/L) on colon of rats in vitro. A: Effects of OFQ on the contractile activity of longitudinal muscle strips obtained from the rat proximal colon; B: Different effects of OFQ (10^-9-10^-6 mol/L) on increment of tension in two groups of rats. ^aP < 0.05 vs 1 × 10^-9 mol/L; ^bP < 0.01 vs 1 × 10^-9 mol/L; C: In the presence of TTX (10^-6 mol/L), OFQ (10^-6 mol/L) failed to evoke additional contractions; D: The response to OFQ (1 × 10^-6 mol/L) was not affected by naloxone (1 × 10^-6 mol/L).

Figure 2 Effects of OFQ on colon of rats in vivo. A: Intravenous administration of OFQ (1 μg/kg) caused phasic contractions in the colon. B: Naloxone (300 μg/kg) has no effects on phasic contractions caused by intravenous administration of OFQ (1 μg/kg)in the proximal colon. C: Intravenous administration of OFQ (1 μg/kg) caused phasic contractions in the proximal colon in two groups.

Figure 3 A: Expression of OFQ in the myenteric plexus of colon in control group. SP × 200; B: Strong positive expression of OFQ in colon of control group. SP × 400; C: Weaker positive expression of OFQ in colon of model group. SP × 400.