Effects of 3, 4-Dihydroxyacetophenone on hypoxic vasoconstriction in isolated pulmonary and basilar arterial rings

Abstract

The effects of 3, 4-DHAP on hypoxic vasoconstriction response in pulmonary (PA) and basilar arterial (BA) rings of rabbits and their mechanism were compared in vitro.

3,4-DHAP in different concentration (2. 64 × 10^-4,7. 92 × 10^-4,2. 376 × 10^-3 mol/L) decreased the basal tone of PA rings by 32. 39 ± 9. 4 mg, 68. 96± 26. 54 mg and 145. 60 ± 58. 07 mg respectively, while the tension of the BA rings was decreased by 13. 80 ±5. 08 mg, 17.18 ± 3. 36 mg and 25. 00 ± 4. 02 mg respectively. In PA rings it also decreased the percentage increase in tension induced by hypoxia (TIH%) from the control value 48.82 ± 5.75% to 10.02 ± 3.62%, 2. 14 ± 0.96%, and 0. 00 % respectively, while in BA rings from 27. 27 ± 5.78% to 11. 23 ± 2.71%, 7.49 ± 1.62%, and 1.45 ± 1.13% respectively. The effects of 3, 4-DHAP on TIH% were partially blocked by indomethacin 10 M and L-NAME 10 M.

The results showed that 3, 4-DHAP can decrease the hypoxic pulmonary and basilar vasoconstriction in vitro, which can be partially inhibited by cyclooxygenase inhibitor and NO/EDRF inhibitor.

Keywords

pulmonary artery / basilar artery / hypoxia / 3, 4 Dihydroxyacetophenone