guinea-pig taenia coli strips that had been incubated with [ 3h ] arachidonic acid , constantly released [ 3h ] arachidonic acid and [ 3h ] prostaglandin e and a prostaglandin which cochromatographed with prostaglandin e but could not be converted to prostaglandin b by alkali and was shown to be 6-ketoprostaglandin f1 alpha .
C0033554
prostaglandin
C0033557
prostaglandin b