Skip to main content
Figure 5 | Behavioral and Brain Functions

Figure 5

From: Effects of mu- and kappa-2 opioid receptor agonists on pain and rearing behaviors

Figure 5

The effects of morphine and GR89,696 on reaching activity and cumulative rearing duration following visceral pain induction was determined. Acetic acid was injected (intraperitoneal) as an acute painful stimulus and produced a significant decrease (*P < 0.05, compared to baseline) in both reaching number (A) and rearing duration (B) during the first 15 min post-injection. Animals were fully recovered by 24 h, as their rearing behavior returned to baseline levels. GR89,696 (N = 8, 1.25 × 10-4 mg/kg, subcutaneous) was ineffective and morphine (N = 8, 0.5 mg/kg) was only partially effective for blocking this visceral pain induction, as demonstrated by a decrease in reaching number (C) and rearing duration (D). For (C, D), *P < 0.05 as compared to naïve animals.

Back to article page