Fig. 1.

HPLC analysis of arachidonic acid (AA) lipoxygenase metabolites showing the radioactivity counts/min (CPM) (A, C, E) and UV absorbance at 235 nm (B, D, F). A: [¹⁴C]AA metabolites of mouse aorta in the presence of a cyclooxygenase inhibitor, indomethacin (10 μM). Aortic rings were incubated with [¹⁴C]AA, and metabolites were extracted and resolved on RP-HPLC using solvent system I. The hydroxyeicosatetraenoic acid (HETE) fraction was collected for further analysis. Migration times of known standards are indicated. The UV absorbance at 235 nm of 12- and 15-HETE standards is shown in B. C: normal phase (NP)-HPLC of the HETE fraction collected from reverse phase (RP)-HPLC (A) using solvent system II. The [¹⁴C]-labeled metabolite comigrated with 12-HETE standard (UV absorbance was monitored at 235 nm) (D). E and F: the biological 12-HETE peak from C was collected, unlabeled 12(S)- and 12(R)-HETE (2:1 ratio) added, and resolved on a chiral HPLC column using solvent system III. UV absorbance was monitored at 235 nm. Retention time of the radioactive biological 12-HETE (E) comigrated with the 12(S)-HETE standard (F).