Table 1. The results obtained from hot-plate and tail-flick analgesia tests in forty male rats that were randomly assigned to five groups according to the treatment received: Group I: Control; Group II: Morphine; Group III: Apelin-13; Group IV: Apelin-13+L-NAME; Group V: Apelin-13+Ondansetron.

L-NAME: Nw-nitro-L-arginine methyl ester, min: minute, Data were expressed as median (Min-Max), *: significantly different from Control group (Mann-Whitney U test, p <0.05), †: significantly different from Morphine group (Mann-Whitney U test, p <0.05), ‡: significantly different from Apelin-13 group (Mann-Whitney U test, p<0.05).