Anion-exchange chromatography of the ethanol extract and western blotting of eluted fractions. ( Upper ) Absorbed proteins were eluted with a liner gradient of 20–500 mM ammonium bicarbonate (pH 8.7) from chub mackerel pituitaries on DEAE MemSEq 1010 cartridge. Fractions absorbance read at 280 nm. ( Lower ) (A) Western blotting with 003 antisera. (B) Western blotting with 299 antisera. Lane number indicates fraction number. Antisera used were Fh FSHβ 50–60 (003 antisera) and Fh LHβ 91–106 (299 antisera), raised against synthetic fragment peptides of mummichog (Fundulus heteroclitus) FSHβ and LHβ .