Methiothepin hydrochloride (non-selective 5-HT antagonist), indomethacin hydrochloride (cyclooxygenase inhibitor), tetraethylammonium (TEA, the nonspecific K+ channel blockers), L-NAME (nonspecific NOS inhibitor Nw-nitro-L-arginine methyl ester) and prazosin hydrochloride (α1 antagonist) were purchased from Sigma Aldrich (St. Louis, MO, USA). SB 269970 (selective 5-HT7 antagonist), BRL 15572 (selective 5-HT1D antagonist) and OHB12 (NO scavenger) were purchased from Tocris (Bristol, UK). Lerimazoline hydrochloride and phenylephrine hydrochloride were kindly donated from Zdravlje Actavis, Leskovac, Serbia.
All drugs, except indomethacin, were prepared as concentrated stocks in distillated water before dilution to the final concentration each day and stored at 4℃ during the experiment. Indomethacin was initially dissolved in 1% DMSO with subsequent dilutions carried out in distillated water. Drug concentrations are described as final molar concentrations in the tissue bath.
All drugs, except indomethacin, were prepared as concentrated stocks in distillated water before dilution to the final concentration each day and stored at 4℃ during the experiment. Indomethacin was initially dissolved in 1% DMSO with subsequent dilutions carried out in distillated water. Drug concentrations are described as final molar concentrations in the tissue bath.