Effects of CB1-agonist (AEA) and 5НТ1А-agonists (DPAT) alone administration on nociceptive (PP) thresholds in (A) intact animals (int) and (B) animals subjected to 1 hour of heat stress (1h HS) without and after pretreatment with CB1- and 5НТ1А-antagonists (AM and NAN, respectively). PP-thresholds are represented as mean values ± S.E.M. in arbitrary units (AU). ***p < 0.001, **p < 0.01, *p < 0.05 vs. controls. A. +++p < 0.001, ++p < 0.01 vs. int+AEA+DPAT. int+NAN+DPAT were compared to int+DPAT – xxxp < 0.001, xxp < 0.01; int+AM+AEA were compared to int+AEA – $$$ p < 0.001. B. +++p < 0.001, ++p < 0.01 vs. 1h HS; xxxp < 0.001, xxp < 0.01 vs. 1h HS+AEA+DPAT. 1h HS+NAN+DPAT were compared to 1h HS+DPAT – $$$p < 0.001, $$p < 0.01; 1h HS+AM+AEA were compared to 1h HS+AEA – &&&p < 0.001.