PGF1α is the putative metabolite of DGLA via the COX pathway. Both PGF1α and PGF2α have been shown to act as priming pheromones for male Atlantic salmon with a threshold concentration of 10−11 M. PGF1α binds to the ovine corpus luteum FP receptor at only 8% of the relative potency of PGF2α. It is only half as active as PGF2α in inducing human respiratory smooth muscle contractions in vitro.